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Drysdale M, Tan L, Martin A, Fuhrer IB, Duparc S, Sharma H. Plasmodium vivax in Children: Hidden Burden and Conspicuous Challenges, a Narrative Review. Infect Dis Ther 2023; 12:33-51. [PMID: 36378465 PMCID: PMC9868225 DOI: 10.1007/s40121-022-00713-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2022] [Accepted: 10/05/2022] [Indexed: 11/16/2022] Open
Abstract
There has been progress towards decreasing malaria prevalence globally; however, Plasmodium vivax has been less responsive to elimination efforts compared with Plasmodium falciparum. P. vivax malaria remains a serious public health concern in regions where it is the dominant species (South and South-East Asia, the Eastern Mediterranean region, and South America) and is increasingly recognized for its contribution to overall morbidity and mortality worldwide. The incidence of P. vivax decreases with increasing age owing to rapidly acquired clinical immunity and there is a disproportionate burden of P. vivax in infants and children, who remain highly vulnerable to severe disease, recurrence, and anemia with associated developmental impacts. Diagnosis is sometimes difficult owing to the sensitivity of diagnostic tests to detect low levels of parasitemia. Additionally, the propensity of P. vivax to relapse following reactivation of dormant hypnozoites in the liver contributes to disease recurrence in infants and children, and potentiates morbidity and transmission. The 8-aminoquinolines, primaquine and tafenoquine, provide radical cure (relapse prevention). However, the risk of hemolysis in patients with glucose-6-phosphate dehydrogenase (G6PD) deficiency necessitates testing prior to administration of 8-aminoquinolines, which has limited their uptake. Additional challenges include lack of availability of pediatric dose formulations and problems with adherence to primaquine owing to the length of treatment recommended. A paucity of data and studies specific to pediatric P. vivax malaria impacts the ability to deliver targeted interventions. It is imperative that P. vivax in infants and children be the focus of future research, control initiatives, and anti-malarial drug development.
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Affiliation(s)
| | - Lionel Tan
- GSK, 980 Great West Road, Brentford, TW8 9GS Middlesex UK
| | - Ana Martin
- GSK, 980 Great West Road, Brentford, TW8 9GS Middlesex UK
| | | | | | - Hema Sharma
- GSK, 980 Great West Road, Brentford, TW8 9GS Middlesex UK
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Trends of Malaria Prevalence in Selected Districts of Kaffa Zone, Southwest Ethiopia. J Trop Med 2022; 2022:3556140. [PMID: 36274749 PMCID: PMC9586818 DOI: 10.1155/2022/3556140] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/28/2022] [Accepted: 10/03/2022] [Indexed: 11/18/2022] Open
Abstract
Background Malaria remains one of the world's major public health issues, particularly in low- and middle-income countries. In Ethiopia, cases have declined over the last decade, and attempts to eradicate the illness are underway. The purpose of this study was to determine trends in malaria prevalence in selected areas of the Kaffa zone during the last five years (Decha and Gimbo districts). Methods All malaria cases registered from 2017 to 2021 were reviewed to assess the trends of malaria prevalence. A checklist was used to collect the secondary data from registers and entered it into an Excel spreadsheet, which was then exported to the Statistical Package for the Social Sciences (SPSS) version 25.0 for analysis. The malaria incidence rate was calculated with the total number of person-years as the denominator and the number of new cases as the numerator. Seasons, years, gender, age, and malaria parasite species were all used to show trends in malaria transmission in the areas. Tables and figures were used to present the data. Results Out of 20,045 individuals screened for malaria, 13.6% (2,732/20,045) of them were recorded to have Plasmodium species tested using microscopy and rapid diagnostic test (RDT). Plasmodium falciparum, Plasmodium vivax, and mixed infections (Plasmodium falciparum + Plasmodium vivax) accounted for 1200 (5.9%), 1114 (5.56%), and 418 (2.09%) of the confirmed malaria cases, respectively. Overall, malaria incidence decreased with an interannual variation, from 4.08 cases per 1000 person-years in 2017 to 3.62 cases per 1000 person-years in 2018, then increased to 4.94 cases per 1000 person-years in 2021. Conclusion The malaria trend over the last five years has revealed a nonconsistent pattern of cases in different years. The number of malaria cases has shown an increase over the period of 2017 to 2021. Interannual and intra-annual variations have been observed in the transmission of the disease.
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Zewude BT, Debusho LK, Diriba TA. Multilevel logistic regression modelling to quantify variation in malaria prevalence in Ethiopia. PLoS One 2022; 17:e0273147. [PMID: 36174003 PMCID: PMC9521912 DOI: 10.1371/journal.pone.0273147] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Accepted: 08/03/2022] [Indexed: 11/19/2022] Open
Abstract
Background
Ethiopia has low malaria prevalence compared to most other malaria-endemic countries in Africa. However, malaria is still a major public health problem in the country. The binary logistic regression model has been widely used to analyse malaria indicator survey (MIS) data. However, most MIS have a hierarchical structure which may result in dependent data. Since this model assumes that conditional on the covariates the malaria statuses of individuals are independent, it ignores potential intra-cluster correlation among observations within a cluster and may generate biased analysis results and conclusions. Therefore, the aim of this study was to quantify the variation in the prevalence of malaria between sample enumeration areas (SEAs) or clusters, the effects of cluster characteristics on the prevalence of malaria using the intra-class correlation coefficient as well as to identify significant factors that affect the prevalence of malaria using the multilevel logistic regression modelling in three major regions of Ethiopia, namely Amhara, Oromia and Southern Nations, Nationalities and Peoples’ (SNNP).
Methods
Dataset for three regional states extracted from the 2011 Ethiopian National Malaria Indicator Surveys (EMIS) national representative samples was used in this study. It contains 9272 sample individuals selected from these regions. Various multilevel models with random sample SEA effects were applied taking into account the survey design weights. These weights are scaled to address unequal probabilities of selection within clusters. The spatial clustering of malaria prevalence was assessed applying Getis-Ord statistic to best linear unbiased prediction values of model random effects.
Results
About 53.82 and 28.72 per cents of the sampled households in the study regions had no mosquito net and sprayed at least once within the last 12 months, respectively. The results of this study indicate that age, gender, household had mosquito nets, the dwelling has windows, source of drinking water, the two SEA-level variables, i.e. region and median altitude, were significantly related to the prevalence of malaria. After adjusting for these seven variables, about 45% of the residual variation in the prevalence of malaria in the study regions was due to systematic differences between SEAs, while the remaining 55% was due to unmeasured differences between persons or households. The estimated MOR, i.e. the unexplained SEA heterogeneity, was 4.784. This result suggests that there is high variation between SEAs in the prevalence of malaria. In addition, the 80% interval odds ratios (IORs) related to SEA-level variables contain one suggesting that the SEA variability is large in comparison with the effect of each of the variable.
Conclusions
The multilevel logistic regression with random effects model used in this paper identified five individual / household and two SEA-level risk factors of malaria infection. Therefore, the public health policy makers should pay attentions to those significant factors, such as improving the availability of pure drinking water. Further, the findings of spatial clustering provide information to health policymakers to plan geographically targeted interventions to control malaria transmission.
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Affiliation(s)
- Bereket Tessema Zewude
- Department of Statistics, University of South Africa, Johannesburg, South Africa
- * E-mail:
| | | | - Tadele Akeba Diriba
- Department of Statistics, University of South Africa, Johannesburg, South Africa
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Nega D, Abera A, Gidey B, Mekasha S, Abebe A, Dillu D, Mehari D, Assefa G, Hailu S, Haile M, Etana K, Solomon H, Tesfaye G, Nigatu D, Destaw Z, Tesfaye B, Serda B, Yeshiwondim A, Getachew A, Teka H, Nahusenay H, Abdelmenan S, Reda H, Bekele W, Zewdie A, Tollera G, Assefa A, Tasew G, Woyessa A, Abate E. Baseline malaria prevalence at the targeted pre-elimination districts in Ethiopia. BMC Public Health 2021; 21:1996. [PMID: 34732150 PMCID: PMC8567662 DOI: 10.1186/s12889-021-12036-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Accepted: 10/18/2021] [Indexed: 12/05/2022] Open
Abstract
Background Encouraged by the previous success in malaria control and prevention strategies, the Ethiopian ministry of health launched malaria elimination with a stepwise approach by primarily targeting the low-transmission Districts and their adjacent areas/zones in order to shrink the country’s malaria map progressively. Hence, this community survey was conducted to establish baseline malaria information at the preliminary phase of elimination at targeted settings. Methods A community-based cross-sectional survey was conducted at 20 malaria-elimination targeted Districts selected from five Regional states and one city administration in Ethiopia. The GPS-enabled smartphones programmed with Open Data Kit were used to enumerate 9326 study households and collect data from 29,993 residents. CareStart™ Malaria PAN (pLDH) Rapid Diagnostic Tests (RDTs) were used for blood testing at the field level. Armpit digital thermometers were used to measure axillary temperature. Result Overall malaria prevalence by RDTs was 1.17% (339/28973). The prevalence at District levels ranged from 0.0 to 4.7%. The proportion of symptomatic cases (axillary temperature > 37.5oc) in the survey was 9.2% (2760/29993). Among the 2510 symptomatic individuals tested with RDTs, only 3.35% (84/2510) were malaria positive. The 75.2% (255/339) of all malaria positives were asymptomatic. Of the total asymptomatic malaria cases, 10.2% (26/255) were under-five children and 89.8% (229/255) were above 5 years of age. Conclusion The study shows a decrease in malaria prevalence compared to the reports of previous malaria indicator surveys in the country. The finding can be used as a baseline for measuring the achievement of ongoing malaria elimination efforts. Particularly, the high prevalence of asymptomatic individuals (0.88%) in these transmission settings indicates there may be sustaining hidden transmission. Therefore, active case detection with more sensitive diagnostic techniques is suggested to know more real magnitude of residual malaria in the elimination-targeted areas.
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Affiliation(s)
- Desalegn Nega
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia.
| | - Adugna Abera
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | | | - Sindew Mekasha
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Abnet Abebe
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Dereje Dillu
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Degu Mehari
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Samuel Hailu
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | - Kebede Etana
- Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | | | | | - Zelalem Destaw
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Berhane Tesfaye
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Belendia Serda
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Asnakew Yeshiwondim
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Assefaw Getachew
- Malaria Control and Elimination Partnership in Africa (MACEPA) at PATH, Addis Ababa, Ethiopia
| | - Hiwot Teka
- President's Malaria Initiative (PMI), Addis Ababa, Ethiopia
| | | | | | - Hailemariam Reda
- Clinton Health Access Initiative, Inc. (CHAI), Addis Ababa, Ethiopia
| | - Worku Bekele
- World Health Organization (WHO), Addis Ababa, Ethiopia
| | - Ayele Zewdie
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | | | | | - Geremew Tasew
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Adugna Woyessa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Ebba Abate
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
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Carrel M, Kim S, Mwandagalirwa MK, Mvuama N, Bala JA, Nkalani M, Kihuma G, Atibu J, Diallo AO, Goel V, Thwai KL, Juliano JJ, Emch M, Tshefu A, Parr JB. Individual, household and neighborhood risk factors for malaria in the Democratic Republic of the Congo support new approaches to programmatic intervention. Health Place 2021; 70:102581. [PMID: 34020231 PMCID: PMC8328915 DOI: 10.1016/j.healthplace.2021.102581] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 04/23/2021] [Accepted: 05/04/2021] [Indexed: 11/25/2022]
Abstract
BACKGROUND The Democratic Republic of the Congo (DRC) remains one of the countries most impacted by malaria despite decades of control efforts, including multiple mass insecticide treated net (ITN) distribution campaigns. The multi-scalar and complex nature of malaria necessitates an understanding of malaria risk factors over time and at multiple levels (e.g., individual, household, community). Surveillance of households in both rural and urban settings over time, coupled with detailed behavioral and geographic data, enables the detection of seasonal trends in malaria prevalence and malaria-associated behaviors as well as the assessment of how the local environments within and surrounding an individual's household impact malaria outcomes. METHODS Participants from seven sites in Kinshasa Province, DRC were followed for over two years. Demographic, behavioral, and spatial information was gathered from enrolled households. Malaria was assessed using both rapid diagnostic tests (RDT) and polymerase chain reaction (PCR) and seasonal trends were assessed. Hierarchical regression modeling tested associations between behavioral and environmental factors and positive RDT and PCR outcomes at individual, household and neighborhood scales. RESULTS Among 1591 enrolled participants, malaria prevalence did not consistently vary seasonally across the sites but did vary by age and ITN usage. Malaria was highest and ITN usage lowest in children ages 6-15 years across study visits and seasons. Having another member of the household test positive for malaria significantly increased the risk of an individual having malaria [RDT: OR = 4.158 (2.86-6.05); PCR: OR = 3.37 (2.41-4.71)], as did higher malaria prevalence in the 250 m neighborhood around the household [RDT: OR = 2.711 (1.42-5.17); PCR: OR = 4.056 (2.3-7.16)]. Presence of water within close proximity to the household was also associated with malaria outcomes. CONCLUSIONS Taken together, these findings suggest that targeting non-traditional age groups, children >5 years old and teenagers, and deploying household- and neighborhood-focused interventions may be effective strategies for improving malaria outcomes in high-burden countries like the DRC.
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Affiliation(s)
- Margaret Carrel
- Department of Geographical & Sustainability Sciences, 305 Jessup Hall, University of Iowa, Iowa City, IA, 52245, USA.
| | - Seungwon Kim
- Department of Geographical & Sustainability Sciences, 305 Jessup Hall, University of Iowa, Iowa City, IA, 52245, USA.
| | - Melchior Kashamuka Mwandagalirwa
- Department of Epidemiology, CB7435, McGavran-Greenberg Hall, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA; Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Nono Mvuama
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Joseph A Bala
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Marthe Nkalani
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Georges Kihuma
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Joseph Atibu
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Alpha Oumar Diallo
- Department of Epidemiology, CB7435, McGavran-Greenberg Hall, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Varun Goel
- Department of Geography, CB3220, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Kyaw L Thwai
- Department of Epidemiology, CB7435, McGavran-Greenberg Hall, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Jonathan J Juliano
- Department of Epidemiology, CB7435, McGavran-Greenberg Hall, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA; Division of Infectious Diseases, School of Medicine, CB#7030, 130 Mason Farm Road, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Michael Emch
- Department of Geography, CB3220, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
| | - Antoinette Tshefu
- Ecole de Sante Publique, Faculte de Medecine, University of Kinshasa, Kinshasa, Democratic Republic of the Congo, USA.
| | - Jonathan B Parr
- Division of Infectious Diseases, School of Medicine, CB#7030, 130 Mason Farm Road, University of North Carolina-Chapel Hill, Chapel Hill, NC, 27599, USA.
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Spatial and genetic clustering of Plasmodium falciparum and Plasmodium vivax infections in a low-transmission area of Ethiopia. Sci Rep 2020; 10:19975. [PMID: 33203956 PMCID: PMC7672087 DOI: 10.1038/s41598-020-77031-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 11/02/2020] [Indexed: 11/23/2022] Open
Abstract
The distribution of malaria infections is heterogeneous in space and time, especially in low transmission settings. Understanding this clustering may allow identification and targeting of pockets of transmission. In Adama district, Ethiopia, Plasmodium falciparum and P. vivax malaria patients and controls were examined, together with household members and immediate neighbors. Rapid diagnostic test and quantitative PCR (qPCR) were used for the detection of infections that were genetically characterized by a panel of microsatellite loci for P. falciparum (26) and P. vivax (11), respectively. Individuals living in households of clinical P. falciparum patients were more likely to have qPCR detected P. falciparum infections (22.0%, 9/41) compared to individuals in control households (8.7%, 37/426; odds ratio, 2.9; 95% confidence interval, 1.3–6.4; P = .007). Genetically related P. falciparum, but not P. vivax infections showed strong clustering within households. Genotyping revealed a marked temporal cluster of P. falciparum infections, almost exclusively comprised of clinical cases. These findings uncover previously unappreciated transmission dynamics and support a rational approach to reactive case detection strategies for P. falciparum in Ethiopia.
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Aschale Y, Ayehu A, Worku L, Addisu A, Zeleke AJ, Bayih AG, Lemma W. Anopheles gambiae s.l (Diptera: Culicidae) seasonal abundance, abdominal status and parity rates in Metema-Armachiho lowland, Northwest Ethiopia. BMC Infect Dis 2020; 20:333. [PMID: 32393183 PMCID: PMC7216343 DOI: 10.1186/s12879-020-05068-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Accepted: 05/03/2020] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Malaria is a life threating vector borne disease caused by different Plasmodium parasites. Metema and Armachiho are two of the top five malaria endemic areas among the districts of Amhara region in Ethiopia. Transmission pattern is seasonal and migrant laborers who visit these areas for employment in mechanized agriculture are highly affected. The aim of this study was to investigate seasonal abundance, abdominal status and parity rate of An.gambiae s.l in Metema-Armachiho lowlands, Northwest Ethiopia. METHOD A 1 year longitudinal entomological study was conducted in Metema-Armachiho lowlands from June 2016-May 2017. Mosquitoes were collected using CDC-light traps in indoor and outdoor sites for four consecutive days in each month. A total of eight standard battery operated CDC-light traps were used to collect mosquitoes. Female mosquitoes were classed as unfed, fed or gravid under a dissecting microscope. The ovaries of all unfed An.gambiae s.l mosquitoes were examined for evidence of parity. Data were entered and analyzed using SPSS-20 software. Chi-square test was applied to show significant difference between variables. P-value< 0.05 was taken as statistically significant. RESULTS Of the total 1253 mosquitoes collected, 713 (552 female, 161 male) were culex and 540 (501 female, 39 male) were An.gambiae s.l. About 50.9% were collected in June-August 2016, 21.7% in September-November 2016, 12.0% in December 2016-February 2017 and 15.4% in March to May 2017. Of the total, 57.2 and 42.8% of the An.gambiae s.l were collected from indoor and outdoor sites respectively. Of the total females collected, 76.8% were unfed; of which 69.4% were parous. Significantly higher number of female An.gambiae s.l were collected in indoor and there was significant difference in abdominal status of An.gambiae s.l mosquitoes collected in different season (P < 0.05). CONCLUSIONS Highest number of An.gambiae s.l was observed from June-August followed by September-November. The parity rate of An.gambiae s.l was high and there was significant difference in abdominal status of An.gambiae s.l collected in different season.
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Affiliation(s)
- Yibeltal Aschale
- Department of Medical Parasitology, College of Health Sciences, Debre Markos University, P.O. Box: 269, Debre Markos, Ethiopia
| | - Animen Ayehu
- Department of Medical Parasitology, College of Medicine and Health Sciences, Bahir Dar University, Bahir Dar, Ethiopia
| | - Ligabaw Worku
- Department of Medical Parasitology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Ayenew Addisu
- Director General,Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Ayalew Jejaw Zeleke
- Department of Medical Parasitology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Abebe Genetu Bayih
- Director General,Armauer Hansen Research Institute (AHRI), Addis Ababa, Ethiopia
| | - Wossenseged Lemma
- Department of Medical Parasitology, School of Biomedical and Laboratory Sciences, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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Ipa M, Widawati M, Laksono AD, Kusrini I, Dhewantara PW. Variation of preventive practices and its association with malaria infection in eastern Indonesia: Findings from community-based survey. PLoS One 2020; 15:e0232909. [PMID: 32379812 PMCID: PMC7205284 DOI: 10.1371/journal.pone.0232909] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/23/2020] [Indexed: 12/23/2022] Open
Abstract
Background Geographical variation may likely influence the effectiveness of prevention efforts for malaria across Indonesia, in addition to factors at the individual level, household level, and contextual factors. This study aimed to describe preventive practices at individual and a household levels applied by rural communities in five provinces in eastern Indonesia and its association with the incidence of malaria among adult (≥15 years) populations. Methods This study analyzed a subset of data of nationally representative community-based survey 2018 Riset Kesehatan Dasar (Riskesdas). Data for socio-demographic (age, gender, education and occupation) and preventive behaviors (use of mosquito bed nets while slept, insecticide-treated mosquito nets (ITNs), mosquito repellent, mosquito electric rackets, mosquito coil/electric anti-mosquito mats, and mosquito window screen) were collected. Data were analyzed using bivariate and multivariable logistic regression model. Results Total of 56,159 respondents (n = 23,070 households) living in rural areas in Maluku (n = 8044), North Maluku (n = 7356), East Nusa Tenggara (n = 23,254), West Papua (n = 5759) and Papua (n = 11,746) were included in the study. In the multivariable models, using a bed net while slept likely reduced the odds of self-reported malaria among Maluku participants. Reduced odds ratios of self-reported malaria were identified in those participants who used ITNs (North Maluku, ENT, Papua), repellent (Maluku, West Papua, Papua), anti-mosquito racket (ENT), coil (Maluku, North Maluku, Papua) and window screen (West Papua, Papua). Conclusion Our study concluded that the protective effects of preventive practices were varied among localities, suggesting the need for specific intervention programs.
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Affiliation(s)
- Mara Ipa
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, National Ministry of Health of Indonesia, Pangandaran, West Java, Indonesia
- * E-mail:
| | - Mutiara Widawati
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, National Ministry of Health of Indonesia, Pangandaran, West Java, Indonesia
| | - Agung Dwi Laksono
- Center of Research and Development of Humanities and Health Management, National Institute of Health Research and Development, National Ministry of Health of Indonesia, Jakarta, Indonesia
| | - Ina Kusrini
- Magelang Unit for Health Research and Development, National Institute of Health Research and Development, National Ministry of Health of Indonesia, Magelang, Central Java, Indonesia
| | - Pandji Wibawa Dhewantara
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, National Ministry of Health of Indonesia, Pangandaran, West Java, Indonesia
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Esayas E, Woyessa A, Massebo F. Malaria infection clustered into small residential areas in lowlands of southern Ethiopia. Parasite Epidemiol Control 2020; 10:e00149. [PMID: 32368628 PMCID: PMC7190761 DOI: 10.1016/j.parepi.2020.e00149] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/25/2019] [Accepted: 04/15/2020] [Indexed: 11/21/2022] Open
Abstract
Malaria is a complex disease and its distribution is not random in endemic areas, and hence areas with low malaria transmission require fine spatial sampling and careful follow-up to identify the hot spots for effective resource utilization to control malaria. The present study is aimed to assess malaria infection in both humans and mosquitoes in a small residential lowland area of southern Ethiopia from July to December 2016. A repeated cross-sectional household survey was conducted in Kolla-Shara Kebele (village) to describe the distribution of malaria and infectious mosquitoes. For the parasitological surveys, a total of 90 households were randomly selected from five sub-villages in equal proportion. About a quarter of the total households included for the surveys were randomly selected for entomological surveys. A P-value of <0.05 was used as a cut-off point for statistical significance. More than a third (35.1%, 46 of 131) febrile cases were microscopically confirmed malaria positive. Above half (58.7%, 27 of 46) of those positive cases were due to P. falciparum and the rest (41.3%, 19 of 46) were due to P. vivax. This study identified two of the five sub-villages as independent clusters with higher risk of malaria infection. Four times higher relative risk (RR) of malaria infection was documented in Abullo sub-village compared to the others (RR = 3.87; P = 0.002). Most of the falciparum malaria cases were aggregated in these sub-villages. About six infectious bites of An. arabiensis per person was recorded during the survey. The infectious bite per person was 17.0 in Abullo and 10.6 in Erze clusters where higher human infections were detected. It is clearly indicated that a smaller portion of the population carry higher malaria cases and infectious bites. Malaria interventions targeting such areas could be effective in the context of malaria elimination strategy in Ethiopia, which consider district as a planning and implementing unit. Future research would preferably be designed to perform long duration of follow-up to identify the appropriate period for interventions and more participants with more heterogeneous villages and districts.
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Affiliation(s)
- Endashaw Esayas
- Arba Minch University, Department of Biology, Arba Minch, Ethiopia.,Ethiopian Federal Ministry of Health, Harari Regional Health Bureau, Malaria Control and Elimination Program, Harar, Ethiopia
| | - Adugna Woyessa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Fekadu Massebo
- Arba Minch University, Department of Biology, Arba Minch, Ethiopia
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Bashir IM, Nyakoe N, van der Sande M. Targeting remaining pockets of malaria transmission in Kenya to hasten progress towards national elimination goals: an assessment of prevalence and risk factors in children from the Lake endemic region. Malar J 2019; 18:233. [PMID: 31299976 PMCID: PMC6624951 DOI: 10.1186/s12936-019-2876-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 07/08/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND With an overall decline of malaria incidence, elimination of malaria is gradually becoming the next target for many of countries affected by the disease. In Kenya the national malaria control strategy is aiming to reach pre-elimination for most parts of the country. However, considerable heterogeneity in prevalence of the disease within the country and especially the remaining high prevalent region of the Lake endemic region is likely to slow progress towards this target. To achieve a sustained control and an eventual elimination, a clear understanding of drivers of ongoing malaria transmission in remaining hotspots is needed. METHODS Data from the 2015 Malaria Indicator Survey (MIS) were analysed for prevalence of malaria parasitaemia in children (6 months to 14 years) of different countries within the highly endemic Lake region. Univariate and multivariate logistic regression analysis were preformed to explore associations between selected risk factors and being parasitaemic. A predictive model was built for the association between malaria and the risk factors with the aim of identifying heterogeneities of the disease at the lower administrative levels. RESULTS Overall, 604/2253 (27%, 95% CI 21.8-32.2) children were parasitaemic. The highest prevalence was observed in Busia County (37%) and lowest in Bungoma County (18%). Multivariate logistic regression analysis showed that the 10-14 years age group (OR = 3.0, 95% CI 2.3-4.1), households in the poorest socio-economic class (OR = 2.1, 95% CI 1.3-3.3), farming (OR = 1.4, 95% CI 1.2-2.5) and residence in Busia (OR = 4.6, 95% CI 2.1-8.2), Kakamega (OR = 2.6, 95% CI 1.3-5.4), and Migori counties (OR = 4.6 95% CI 2.1-10.3) were associated with higher risk of parasitaemia. Having slept under a long-lasting insecticide-treated bed net (LLIN) was associated with a lower risk (OR = 0.7, 95% CI 0.6-0.9). No association were found between malaria infection and the gender of the child, the household head, and the education status of the household head. DISCUSSION AND CONCLUSION Detailed analysis of malaria prevalence data in a hotspot area can identify new threats and avail opportunities for directing intervention. In the Lake endemic region of Kenya, interventions should be focused more on counties with the highest prevalence, and should target older children as well as children from the lower socio-economic strata. Precisely targeting interventions in remaining hotspots and high-risk populations will likely make impact and accelerate progress towards pre-elimination targets.
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Affiliation(s)
- Ismail Mahat Bashir
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.
| | - Nancy Nyakoe
- Walter Reed Project, Kenya Medical Research Institute, Kisumu, Kenya
| | - Marianne van der Sande
- Department of Public Health, Institute of Tropical Medicine, Antwerp, Belgium.,Julius Global Health Center, Julius Center for Health Sciences and Primary Care, Utrecht University, Utrecht, The Netherlands
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Getachew D, Gebre-Michael T, Balkew M, Tekie H. Species composition, blood meal hosts and Plasmodium infection rates of Anopheles mosquitoes in Ghibe River Basin, southwestern Ethiopia. Parasit Vectors 2019; 12:257. [PMID: 31122286 PMCID: PMC6533711 DOI: 10.1186/s13071-019-3499-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2019] [Accepted: 05/09/2019] [Indexed: 01/25/2023] Open
Abstract
Background Vector control interventions using long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are commonly practiced tools for the control of malaria in Ethiopia. In order to evaluate the effectiveness of these control interventions, and understand the prevailing malaria vectors, their incrimination in disease transmission, and their resting and feeding behavior, we set out to identify the Anopheles species, their blood meal sources, and entomological inoculation rate (EIR) in Ghibe and Darge within the Ghibe River basin, southwestern Ethiopia. Methods Adult Anopheles mosquitoes were sampled both indoors and outdoors from January 2015 to October 2016 using Centers for Disease Control and Prevention (CDC) light traps, pyrethrum spray catch (PSC), artificial pit shelters and mouth aspirators. Mosquito species were morphologically identified, and their blood meal sources and malaria sporozoite rates were assessed using enzyme-linked immunosorbent assays. Results In total, 13 species of Anopheles mosquitoes were identified, among which Anopheles gambiae (s.l.) was the predominant species: 87.9 and 67.7% in Ghibe and Darge, respectively. The mean density of An. gambiae (s.l.) collected per night using CDC light traps was 1.8 and 0.7 outdoors and indoors, respectively, in Ghibe, and 0.125 and 0.07 indoors and outdoors, respectively, in Darge. Anopheles mosquito abundance was higher in houses near the river than in houses far from the river in both study sites. Among Anopheles mosquitoes sampled using CDC light trap catches, 67.6% were unfed and the indoor and outdoor human blood indices of An. gambiae (s.l.) were 58.4 and 15.8%, respectively in Ghibe, while in Darge, they were 57.1 and 50%, respectively. Sporozoite rates were 0.07% for P. vivax and 0.07% for P. falciparum in Ghibe and zero in Darge. In Ghibe, the overall EIRs for P. falciparum and P. vivax were zero and 8.4 infective bites/person/year, respectively, in 2015, while zero and 5.4 infective bites/person/year for P. vivax and P. falciparum, respectively, in 2016. No Plasmodium-positive Anopheles mosquitoes were identified from Darge. Conclusions Anopheles gambiae (s.l.), the principal vector of malaria in Ethiopia was the most abundant species both indoors and outdoors, fed both on human and cattle blood and occurred at higher frequencies near rivers. Anopheles gambiae (s.l.) that were circumsporozoite-positive for Plasmodium species were collected from Ghibe, but not Darge.
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Affiliation(s)
- Dejene Getachew
- Department of Biology, Dire Dawa University, P. O. Box 1362, Dire Dawa, Ethiopia. .,Department of Zoological Sciences, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia.
| | - Teshome Gebre-Michael
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia
| | - Meshesha Balkew
- Abt Associates, PMI VectorLink Ethiopia Project, Addis Ababa, Ethiopia
| | - Habte Tekie
- Department of Zoological Sciences, Addis Ababa University, P. O. Box 1176, Addis Ababa, Ethiopia
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Kim S, Kim Y. Spatially Filtered Multilevel Analysis on Spatial Determinants for Malaria Occurrence in Korea. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16071250. [PMID: 30965608 PMCID: PMC6480462 DOI: 10.3390/ijerph16071250] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2019] [Revised: 03/26/2019] [Accepted: 03/30/2019] [Indexed: 11/16/2022]
Abstract
Since its re-emergence in 1993, the spatial patterns of malaria outbreaks in South Korea have drastically changed. It is well known that complicated interactions between humans, nature, and socio-economic factors lead to a spatial dependency of vivax malaria occurrences. This study investigates the spatial factors determining malaria occurrences in order to understand and control malaria risks in Korea. A multilevel model is applied to simultaneously analyze the variables in different spatial scales, and eigenvector spatial filtering is used to explain the spatial autocorrelation in the malaria occurrence data. The results show that housing costs, average age, rice paddy field ratio, and distance from the demilitarized zone (DMZ) are significant on the level-1 spatial scale; health budget per capita and military base area ratio are significant on the level-2 spatial scale. The results show that the spatially filtered multilevel model provides better analysis results in handling spatial issues.
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Affiliation(s)
- Sehyeong Kim
- Department of Geography, Korea University, 145 Anam-ro, Seoul 02841, Korea.
| | - Youngho Kim
- Department of Geography Education, Korea University, 145 Anam-ro, Seoul 02841, Korea.
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Dhewantara PW, Ipa M, Widawati M. Individual and contextual factors predicting self-reported malaria among adults in eastern Indonesia: findings from Indonesian community-based survey. Malar J 2019; 18:118. [PMID: 30947730 PMCID: PMC6449936 DOI: 10.1186/s12936-019-2758-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2019] [Accepted: 03/30/2019] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Malaria is still an important parasitic infectious disease that affecting poor and vulnerable communities in many developing countries, including Indonesia. During the period of 2010-2017, there have been approximately 2.2 million confirmed malaria cases reported across Indonesia. This study aimed to identify individual, household and village-level factors associated with self-reported malaria among adults more than 15 years of age in Maluku, West Papua and Papua province. METHODS This study analysed a subset of the data from nationally representative population-based Indonesian National Basic Health Research (Riset Kesehatan Dasar) (N = 1,027,763 in 294,959 households in 33 provinces) in 2013. Total of 41,079 individuals (20,326 males and 20,753 females) aged ≥ 15 years in 19,269 households in Maluku, West Papua and Papua provinces were included. Participants were interviewed if they ever had been diagnosed and laboratory confirmed of having malaria by physician in the past 12 months. A mixed effects multilevel logistic regression models were developed to assess the associations between socio-demographical variables at individual, household and village level and self-reported malaria. RESULTS Individuals aged ≥ 15 years in 701 villages in Maluku (n = 11,919), West Papua (n = 8003) and Papua (n = 21,157) were analysed. In all provinces, gender distribution was equally-represented. The prevalence of self-reported malaria was 4.1% (Maluku), 12.4% (West Papua) and 18.8% (Papua). At the individual level, primary industry workers (OR 1.29, 95% CI 1.15-1.46 [Maluku]; OR 1.17, 95% CI 1.09-1.25 [Papua]) and having higher education were associated with self-reporting malaria (OR 0.67, 95% CI 0.53-0.83 [Maluku]; OR 1.27, 95% CI 1.15-1.40 [Papua]). Household level factors include having bed net and better off wealth index were associated with increased self-reporting malaria among West Papua (OR 1.21; 95% CI 1.09-1.34 and OR 1.38; 95% CI 1.17-1.65, respectively) and Papuan (OR 1.12; 95% CI 1.02-1.23 and OR 1.33; 95% CI 1.11-1.57, respectively) adults. Increased odds of self-reporting malaria was associated with time required to reach healthcare facility (OR 1.30, 95% CI 1.01-1.67 [Maluku]). Contextual village-level characteristics such as living in rural (OR 1.31, 95% CI 1.12-1.54 [Maluku]; OR 1.56, 95% CI 1.17-2.07 [West Papua]), higher community education level (OR 1.28, 95% CI 1.02-1.63 [West Papua]; OR 1.45, 95% CI 1.23-1.72 [Papua]), higher community bed net ownerships (OR 0.59 95% CI 0.45-0.77 [West Papua]) were associated with self-reported malaria. CONCLUSIONS Factors associated with self-reported malaria were varied between provinces suggesting locally-specific determinants were exist at individual, household and community-level. This study highlights the need for specific interventions by taking into consideration the contextual factors within the region and involving multi-sectoral collaboration between health authorities and related stakeholders (e.g., bureau of education, bureau of public works and infrastructure) to improve designs in planning and intervention strategies to succesfully eliminate malaria in Maluku and Papua.
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Affiliation(s)
- Pandji Wibawa Dhewantara
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, Ministry of Health of Indonesia, Pangandaran, West Java, 46396, Indonesia. .,School of Veterinary Science, University of Queensland, Gatton, QLD, 4343, Australia.
| | - Mara Ipa
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, Ministry of Health of Indonesia, Pangandaran, West Java, 46396, Indonesia
| | - Mutiara Widawati
- Pangandaran Unit for Health Research and Development, National Institute of Health Research and Development, Ministry of Health of Indonesia, Pangandaran, West Java, 46396, Indonesia
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Jahan F, Khan NH, Wahid S, Ullah Z, Kausar A, Ali N. Malaria epidemiology and comparative reliability of diagnostic tools in Bannu; an endemic malaria focus in south of Khyber Pakhtunkhwa, Pakistan. Pathog Glob Health 2019; 113:75-85. [PMID: 30894081 DOI: 10.1080/20477724.2019.1595904] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
The present study was aimed at elucidation of malaria epidemiology and comparing performance of several diagnostic procedures in Bannu, a highly endemic district of Khyber Pakhtunkhwa, Pakistan. Dried blood spots were collected from patients suspected of malaria visiting a hospital and two private laboratories in district Bannu and processed for species-specific PCR (rRNA). Patients were also screened for malaria through microscopy and RDT. A well-structured questionnaire was used to collect patient information to assess risk factors for malaria. Of 2033 individuals recruited, 21.1% (N = 429) were positive for malaria by at least one method. Overall, positivity detected by PCR was 30.5% (95/311) followed by 17.7% by microscopy (359/2033) and 16.4% by RDT (266/1618). Plasmodium vivax (16.9%, N = 343) was detected as the dominant species followed by Plasmodium falciparum (2.3%, N = 47) and mixed infections (1.2%, N = 39). Microscopy and RDT (Cohen's kappa k = 0.968, p = <0.0001, McNemar test p = 0.069) displayed significant agreement with each other. Satisfactory health, sleeping indoors, presence of health-care facility in vicinity (at an accessible range from home), living in upper middle class and in concrete houses significantly reduced malaria risk; whereas, low literacy level, presence of domestic animals indoors and malaria diagnosis recommended by clinician increased the disease risk. Overall, findings from the study provide reasonable basis for use of RDT as a cost-effective screening tool in field and for clinicians who can proceed with timely treatment of malaria patients. Appropriate management of identified risk factors could contribute to reduction of malaria prevalence in Bannu and its peripheries.
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Affiliation(s)
- Fatima Jahan
- a Department of Zoology , University of Peshawar , Peshawar , Pakistan
| | - Nazma Habib Khan
- a Department of Zoology , University of Peshawar , Peshawar , Pakistan
| | - Sobia Wahid
- a Department of Zoology , University of Peshawar , Peshawar , Pakistan
| | - Zaki Ullah
- b Department of Pharmacy , University of Peshawar , Peshawar , Pakistan
| | - Aisha Kausar
- a Department of Zoology , University of Peshawar , Peshawar , Pakistan
| | - Naheed Ali
- a Department of Zoology , University of Peshawar , Peshawar , Pakistan
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Degarege A, Fennie K, Degarege D, Chennupati S, Madhivanan P. Improving socioeconomic status may reduce the burden of malaria in sub Saharan Africa: A systematic review and meta-analysis. PLoS One 2019; 14:e0211205. [PMID: 30677102 PMCID: PMC6345497 DOI: 10.1371/journal.pone.0211205] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Accepted: 01/09/2019] [Indexed: 11/18/2022] Open
Abstract
Background A clear understanding of the effects of housing structure, education, occupation, income, and wealth on malaria can help to better design socioeconomic interventions to control the disease. This literature review summarizes the relationship of housing structure, educational level, occupation, income, and wealth with the epidemiology of malaria in sub-Saharan Africa (SSA). Methods A systematic review and meta-analysis was conducted following the preferred reporting items for systematic reviews and meta-analyses guidelines. The protocol for this study is registered in PROSPERO (ID=CRD42017056070), an international database of prospectively registered systematic reviews. On January 16, 2016, available literature was searched in PubMed, Embase, CINAHL, and Cochrane Library. All but case studies, which reported prevalence or incidence of Plasmodium infection stratified by socioeconomic status among individuals living in SSA, were included without any limits. Odds Ratio (OR) and Relative Risk (RR), together with 95% CI and p-values were used as effect measures. Heterogeneity was assessed using chi-square, Moran’s I2, and tau2 tests. Fixed (I2<30%), random (I2≥30%) or log-linear dose-response model was used to estimate the summary OR or RR. Results After removing duplicates and screening of titles, abstracts, and full text, 84 articles were found eligible for systematic review, and 75 of them were included in the meta-analyses. Fifty-seven studies were cross-sectional, 12 were prospective cohort, 10 were case-control, and five were randomized control trials. The odds of Plasmodium infection increased among individuals who were living in poor quality houses (OR 2.13, 95% CI 1.56–3.23, I2 = 27.7), were uneducated (OR 1.36, 95% CI 1.19–1.54, I2 = 72.4.0%), and were farmers by occupation (OR 1.48, 95% CI 1.11–1.85, I2 = 0.0%) [p<0.01 for all]. The odds of Plasmodium infection also increased with a decrease in the income (OR 1.02, 95% CI 1.01–1.03, tau2<0.001), and wealth index of individuals (OR 1.25, 95% CI 1.18–1.35, tau2 = 0.028) [p<0.001 for both]. Longitudinal studies also showed an increased risk of Plasmodium infection among individuals who were living in poor quality houses (RR 1.86, 95% CI 1.47–2.25, I2 = 0.0%), were uneducated (OR 1.27, 1.03–1.50, I2 = 0.0%), and were farmers (OR 1.36, 1.18–1.58) [p<0.01 for all]. Conclusions Lack of education, low income, low wealth, living in poorly constructed houses, and having an occupation in farming may increase risk of Plasmodium infection among people in SSA. Public policy measures that can reduce inequity in health coverage, as well as improve economic and educational opportunities for the poor, will help in reducing the burden of malaria in SSA.
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Affiliation(s)
- Abraham Degarege
- Department of Epidemiology, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, United States of America
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
- * E-mail:
| | - Kristopher Fennie
- Department of Epidemiology, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, United States of America
| | - Dawit Degarege
- Ethiopian Ministry of Health Office, Addis Ababa, Ethiopia
| | - Shasank Chennupati
- Department of Epidemiology, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, United States of America
| | - Purnima Madhivanan
- Department of Epidemiology, Robert Stempel College of Public Health & Social Work, Florida International University, Miami, FL, United States of America
- Public Health Research Institute of India, Mysore, India
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Onyiah AP, Ajayi IO, Dada-Adegbola HO, Adedokun BO, Balogun MS, Nguku PM, Ajumobi OO. Long-lasting insecticidal net use and asymptomatic malaria parasitaemia among household members of laboratory-confirmed malaria patients attending selected health facilities in Abuja, Nigeria, 2016: A cross-sectional survey. PLoS One 2018; 13:e0203686. [PMID: 30212496 PMCID: PMC6136754 DOI: 10.1371/journal.pone.0203686] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Accepted: 08/24/2018] [Indexed: 11/18/2022] Open
Abstract
INTRODUCTION In Nigeria, malaria remains a major burden. There is the presupposition that household members could have common exposure to malaria parasite and use of long-lasting insecticidal net (LLIN) could reduce transmission. This study was conducted to identify factors associated with asymptomatic malaria parasitaemia and LLIN use among households of confirmed malaria patients in Abuja, Nigeria. METHODS A cross-sectional survey was conducted from March to August 2016 in twelve health facilities selected from three area councils in Abuja, Nigeria. Participants were selected using multi-stage sampling technique. Overall, we recruited 602 participants from 107 households linked to 107 malaria patients attending the health facilities. Data on LLIN ownership, utilization, and house characteristics were collected using a semi-structured questionnaire. Blood samples of household members were examined for malaria parasitaemia using microscopy. Data were analyzed using descriptive statistics, Chi-square, and logistic regression (α = 0.05). RESULTS Median age of respondents was 16.5 years (Interquartile range: 23 years); 55.0% were females. Proportions of households that owned and used at least one LLIN were 44.8% and 33.6%, respectively. Parasitaemia was detected in at least one family member of 102 (95.3%) index malaria patients. Prevalence of asymptomatic malaria parasitaemia among study participants was 421/602 (69.9%). No association was found between individual LLIN use and malaria parasitaemia (odds ratio: 0.9, 95% confidence interval (95%CI): 0.6-1.3) among study participants. Having bushes around the homes was associated with having malaria parasitaemia (adjusted OR (aOR): 2.7, 95%CI: 1.7-4.2) and less use of LLIN (aOR: 0.4, 95%CI: 0.2-0.9). Living in Kwali (aOR: 0.1, 95% CI: 0.0-0.2) was associated with less use of LLIN. CONCLUSION High prevalence of asymptomatic malaria and low use of LLIN among household members of malaria patients portend the risk of intra-household common source of malaria transmission. We recommend household health education on LLIN use and environmental management. Study to explore the role of preventive treatment of household members of confirmed malaria patient in curbing transmission is suggested. Strategies promoting LLIN use need to be intensified in Kwali.
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Affiliation(s)
- Amaka Pamela Onyiah
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, FCT, Nigeria
- Department of Epidemiology and Medical Statistics, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - IkeOluwapo O. Ajayi
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, FCT, Nigeria
- Department of Epidemiology and Medical Statistics, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Hannah O. Dada-Adegbola
- Department of Medical Microbiology and Parasitology, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Babatunde O. Adedokun
- Department of Epidemiology and Medical Statistics, University of Ibadan, Ibadan, Oyo State, Nigeria
| | - Muhammad S. Balogun
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, FCT, Nigeria
| | - Patrick M. Nguku
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, FCT, Nigeria
| | - Olufemi O. Ajumobi
- Nigeria Field Epidemiology and Laboratory Training Programme, Abuja, FCT, Nigeria
- National Malaria Elimination Programme, Abuja, FCT, Nigeria
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Malede A, Alemu K, Aemero M, Robele S, Kloos H. Travel to farms in the lowlands and inadequate malaria information significantly predict malaria in villages around Lake Tana, northwest Ethiopia: a matched case-control study. Malar J 2018; 17:290. [PMID: 30097037 PMCID: PMC6086053 DOI: 10.1186/s12936-018-2434-y] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2018] [Accepted: 07/30/2018] [Indexed: 11/25/2022] Open
Abstract
Background In Ethiopia, malaria has declined in the last decade; only a small number of cases have been reported, primarily from hotspots. The contribution of house proximity to water bodies and the role of migration in malaria transmission has not yet been examined in detail in northwest Ethiopia. Individual and household-level environmental and socio-demographic drivers of malaria heterogeneity were explored contextually in meso-endemic villages around Lake Tana, northwest Ethiopia. Methods A health facility-based paired age-sex matched case–control study involving 303 matched pairs was undertaken from 10 October 2016, to 30 June 2017. Geo-referencing of case households, control households, proximate water bodies, and health centres was carried out. A pretested and structured questionnaire was used to collect data on socio-demography, household assets, housing, travel history, and malaria intervention measures. Medians (interquartile range) were computed for continuous variables. Pearson’s Chi square/Fisher’s exact test was used to detect significant differences in proportions. Principal component analysis was performed to estimate household wealth. Stratified analysis was used to confirm confounding and interaction. A multivariable conditional logistic regression model was used to detect risk factors for malaria. Results Of 303 malaria cases, 59 (19.5% [15.4–24.3]) were imported malaria cases whereas 244 (80.5% [75.7–84.6]) were locally acquired malaria cases. In bivariate analysis, marital status, educational status, and bed net ownership were significantly associated with malaria cases. In multivariable adjustment, travel to malarious lowlands in the preceding month (adjusted mOR = 7.32; 95% CI 2.40–22.34), household member’s travel to malarious lowlands (adjusted mOR = 2.75; 95% CI 1.02–7.44), and inadequate health information on malaria (adjusted mOR = 1.57; 95% CI 1.03–2.41) were predictors of malaria. Stratified analysis confirmed that elevation of households and travel to malarious lowlands were not effect modifiers. Travel to malarious lowlands had a confounding effect on malaria but elevation of households did not. Conclusions In this study, travel to farms in the lowlands and inadequate health information on malaria were risk factors for malaria in villages around Lake Tana. This evidence is critical for the design of improved strategic interventions that consider imported malaria cases and approaches for accessing health information on malaria control in northwest Ethiopia. Electronic supplementary material The online version of this article (10.1186/s12936-018-2434-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Asmamaw Malede
- Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia.
| | - Kassahun Alemu
- Department of Epidemiology and Biostatistics, Institute of Public Health, University of Gondar, Gondar, Ethiopia
| | - Mulugeta Aemero
- Department of Medical Parasitology, School of Biomedical & Laboratory Sciences, University of Gondar, Gondar, Ethiopia
| | - Sirak Robele
- Ethiopian Institute of Water Resources, Addis Ababa University, Addis Ababa, Ethiopia
| | - Helmut Kloos
- Department of Epidemiology and Biostatistics, University of California, San Francisco, USA
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Bannister-Tyrrell M, Srun S, Sluydts V, Gryseels C, Mean V, Kim S, Sokny M, Peeters Grietens K, Coosemans M, Menard D, Tho S, Van Bortel W, Durnez L. Importance of household-level risk factors in explaining micro-epidemiology of asymptomatic malaria infections in Ratanakiri Province, Cambodia. Sci Rep 2018; 8:11643. [PMID: 30076361 PMCID: PMC6076298 DOI: 10.1038/s41598-018-30193-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/20/2018] [Indexed: 11/09/2022] Open
Abstract
Heterogeneity in malaria risk is considered a challenge for malaria elimination. A cross-sectional study was conducted to describe and explain micro-epidemiological variation in Plasmodium infection prevalence at household and village level in three villages in Ratanakiri Province, Cambodia. A two-level logistic regression model with a random intercept fitted for each household was used to model the odds of Plasmodium infection, with sequential adjustment for individual-level then household-level risk factors. Individual-level risk factors for Plasmodium infection included hammock net use and frequency of evening outdoor farm gatherings in adults, and older age in children. Household-level risk factors included house wall material, crop types, and satellite dish and farm machine ownership. Individual-level risk factors did not explain differences in odds of Plasmodium infection between households or between villages. In contrast, once household-level risk factors were taken into account, there was no significant difference in odds of Plasmodium infection between households and between villages. This study shows the importance of ongoing indoor and peridomestic transmission in a region where forest workers and mobile populations have previously been the focus of attention. Interventions targeting malaria risk at household level should be further explored.
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Affiliation(s)
| | - Set Srun
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Vincent Sluydts
- Institute of Tropical Medicine, Nationalestraat 155, Antwerp, Belgium
- University of Antwerp, Antwerpm, Belgium
| | | | - Vanna Mean
- Ratanakiri Provincial Health Department, Banlung, Cambodia
| | - Saorin Kim
- Institut Pasteur du Cambodge, Phnom Penh, Cambodia
| | - Mao Sokny
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | | | - Marc Coosemans
- Institute of Tropical Medicine, Nationalestraat 155, Antwerp, Belgium
| | | | - Sochantha Tho
- National Centre for Parasitology, Entomology and Malaria Control, Phnom Penh, Cambodia
| | - Wim Van Bortel
- Institute of Tropical Medicine, Nationalestraat 155, Antwerp, Belgium
| | - Lies Durnez
- Institute of Tropical Medicine, Nationalestraat 155, Antwerp, Belgium
- University of Antwerp, Antwerpm, Belgium
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Dear NF, Kadangwe C, Mzilahowa T, Bauleni A, Mathanga DP, Duster C, Walker ED, Wilson ML. Household-level and surrounding peri-domestic environmental characteristics associated with malaria vectors Anopheles arabiensis and Anopheles funestus along an urban-rural continuum in Blantyre, Malawi. Malar J 2018; 17:229. [PMID: 29884176 PMCID: PMC5994107 DOI: 10.1186/s12936-018-2375-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2018] [Accepted: 06/05/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria is increasing in some recently urbanized areas that historically were considered lower risk. Understanding what drives urban transmission is hampered by inconsistencies in how "urban" contexts are defined. A dichotomized "urban-rural" approach, based on political boundaries may misclassify environments or fail to capture local drivers of risk. Small-scale agriculture in urban or peri-urban settings has been shown to be a major risk determinant. METHODS Household-level Anopheles abundance patterns in and around Malawi's commercial capital of Blantyre (~ 1.9 M pop.) were analysed. Clusters (N = 64) of five houses each located at 2.5 km intervals along eight transects radiating out from Blantyre city centre were sampled during rainy and dry seasons of 2015 and 2016. Mosquito densities were measured inside houses using aspirators to sample resting mosquitoes, and un-baited CDC light traps to sample host seeking mosquitoes. RESULTS Of 38,895 mosquitoes captured, 91% were female and 87% were Culex spp. Anopheles females (N = 5058) were primarily captured in light traps (97%). Anopheles abundance was greater during rainy seasons. Anopheles funestus was more abundant than Anopheles arabiensis, but both were found on all transects, and had similar associations with environmental risk factors. Anopheles funestus and An. arabiensis females significantly increased with distance from the urban centre, but this trend was not consistent across all transects. Presence of small-scale agriculture was predictive of greater Anopheles spp. abundance, even after controlling for urbanicity, number of nets per person, number of under-5-year olds, years of education, and season. CONCLUSIONS This study revealed how small-scale agriculture along a rural-to-urban transition was associated with An. arabiensis and An. funestus indoor abundances, and that indoor Anopheles density can be high within Blantyre city limits, particularly where agriculture is present. Typical rural areas with lower house density and greater distance from urban centres reflected landscapes more suitable for Anopheles reproduction and house invasion. However, similar characteristics and elevated Anopheles abundances were also found around some houses within the city limits. Thus, dichotomous designations of "urban" or "rural" can obscure important heterogeneity in the landscape of Plasmodium transmission, suggesting the need for more nuanced assessment of urban malaria risk and prevention efforts.
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Affiliation(s)
- Nicole F Dear
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
| | - Chifundo Kadangwe
- Malaria Alert Centre, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Themba Mzilahowa
- Malaria Alert Centre, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Andy Bauleni
- Malaria Alert Centre, College of Medicine, University of Malawi, Blantyre, Malawi
| | - Don P Mathanga
- Malaria Alert Centre, College of Medicine, University of Malawi, Blantyre, Malawi.,College of Medicine, University of Malawi, Blantyre, Malawi
| | - Chifundo Duster
- Malawi International Center of Excellence for Malaria Research (ICEMR) Molecular Core Laboratory, University of Malawi College of Medicine, Blantyre, Malawi
| | - Edward D Walker
- Department of Microbiology & Molecular Genetics, Michigan State University, East Lansing, MI, USA
| | - Mark L Wilson
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA
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Individual and household characteristics of persons with Plasmodium falciparum malaria in sites with varying endemicities in Kinshasa Province, Democratic Republic of the Congo. Malar J 2017; 16:456. [PMID: 29121931 PMCID: PMC5680818 DOI: 10.1186/s12936-017-2110-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2017] [Accepted: 11/06/2017] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND The Democratic Republic of the Congo (DRC) bears a large share of global malaria burden despite efforts to control and eliminate the disease. More detailed understanding of individual and household level characteristics associated with malaria are needed, as is an understanding of how these characteristics vary spatiotemporally and across different community-level malaria endemicities. An ongoing study in Kinshasa Province is designed to address gaps in prior malaria surveillance in the DRC by monitoring malaria across seasons, age groups and in high and low malaria sites. Across seven sites, 242 households and 1591 individuals are participating in the study. Results of the enrollment questionnaire, rapid diagnostic tests and PCR testing of dried blood spots are presented. RESULTS Overall malaria prevalence in the study cohort is high, 27% by rapid diagnostic test and 31% by polymerase chain reaction, and malaria prevalence is highly varied across very small geographic distances. Malaria prevalence is highest in children aged 6-15. While the majority of households own bed nets, bed net usage is less than 50%. CONCLUSIONS The study cohort will provide an understanding of how malaria persists in populations that have varying environmental exposures, varying community-level malaria, and varying access to malaria control efforts.
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Individual and household factors associated with ownership of long-lasting insecticidal nets and malaria infection in south-central Ethiopia: a case-control study. Malar J 2017; 16:402. [PMID: 28985734 PMCID: PMC5639580 DOI: 10.1186/s12936-017-2048-9] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 09/30/2017] [Indexed: 11/23/2022] Open
Abstract
Background A recent considerable decline in malaria morbidity and mortality in Ethiopia is likely to be followed by changes in the practice of effective preventive measures and malaria risk factors. This study aimed to identify determinants of long-lasting insecticidal nets (LLINs) ownership and risk of malaria infection. Methods A matched case–control study of 191 case and 377 control households was conducted between October 2014 and November 2015 in Adami Tullu district in south-central Ethiopia. Cases were microscopy or rapid diagnostic test confirmed malaria patients identified at three health centers and nine health posts, and matched on age with two neighbourhood controls. Information was collected on socio-demographic factors, house structure, knowledge on malaria and ownership of LLINs. The logistic regression model was used to determine predictors of LLINs ownership and malaria infection. Results All cases were infections due to either Plasmodium falciparum (71.2%) or Plasmodium vivax (28.8%). About 31% of the study households had at least one LLINs. Significant determinants of LLINs ownership were household’s head malaria knowledge [adjusted odds ratio (AOR) = 2.47, 95% confidence interval (CI) 1.44–4.22], educational status [read and write (AOR = 6.88, 95% CI 2.30–20.55), primary education or higher (AOR = 5.40, 95% CI 1.57–18.55)], farmer respondent (AOR = 0.35, 95% CI 0.17–0.76), having ≥ 3 sleeping areas (AOR = 6.71, 95% CI 2.40–18.77) and corrugated roof type (AOR = 2.49, 95% CI 1.36–4.58). This study was unable to identify important risk factors of malaria infection with regard to sex, household wealth index, house structure, ownership of LLINs, keeping livestock inside house, staying overnight outdoor or having malaria during the last 6 months. Conclusions Household socio-economic status, educational status and knowledge on malaria were important predictors of LLINs ownership. Households with farmer respondents were less likely to own LLINs. Addressing these factors could improve household’s ownership of LLINs. The importance of factors associated with malaria infection was less evident in the current low transmission setting, and necessitates further epidemiological study.
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Nissen A, Cook J, Loha E, Lindtjørn B. Proximity to vector breeding site and risk of Plasmodium vivax infection: a prospective cohort study in rural Ethiopia. Malar J 2017; 16:380. [PMID: 28927422 PMCID: PMC5605991 DOI: 10.1186/s12936-017-2031-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2017] [Accepted: 09/14/2017] [Indexed: 11/15/2022] Open
Abstract
Background Despite falling incidence and mortality since the turn of the century, malaria remains an important global health challenge. In the future fight against malaria, greater emphasis will have to be placed on understanding and addressing malaria caused by the Plasmodium vivax parasite. Unfortunately, due to years of neglect and underfunding, there are currently many gaps in knowledge of P. vivax malaria. The aims of the present study were to explore the association between distance to vector breeding site and P. vivax infection in rural Ethiopia, and, secondarily, to test whether this association varies with age. Methods A prospective, cohort study of all residents in the Chano Mille Kebele in southern Ethiopia from April 2009 to March 2011 (n = 8121). Weekly household follow up visits included screening for febrile cases (active surveillance). Participants were also asked to contact the local health centre if they experienced subjective fever between visits (passive surveillance). Plasmodium vivax infection was confirmed using microscopy by two independent readers. Information was collected on demographics and household characteristics including GPS-determined distance to vector breeding site. Data was analysed using Cox regression modelling. Results Overall the P. vivax infection rate was 12.3/1000 person-years (95% CI 10.5–14.5). Mean household distance to breeding site was 2449 m (range 1646–3717 m). Fully adjusted results showed very strong evidence of an association between proximity to breeding site and P. vivax infection: rate ratio = 3.47 (95% CI 2.15–5.60; P < 0.001) comparing the group closest to the breeding site (distance < 2100 m; n = 1383) to the group furthest away (distance > 2700 m; n = 2460). There was no evidence that age was an effect modifier in the association. Conclusion Results showed strong evidence that household proximity to vector breeding site is positively associated with P. vivax infection in rural Ethiopia, and that this association is constant across age groups. The findings might influence how net-distribution and indoor residual spraying campaigns are planned, help guide strategies on water resource development by highlighting potential health effects of man-made dams near human habitats, and add to current educational information given to people living close to breeding sites.
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Affiliation(s)
- Alexander Nissen
- Norwegian Centre for Violence and Traumatic Stress Studies, Nydalen, P.O. Box 181, 0409, Oslo, Norway.
| | - Jackie Cook
- MRC Tropical Epidemiology Group, London School of Hygiene and Tropical Medicine, London, UK
| | - Eskindir Loha
- School of Public and Environmental Health, Hawassa University, Awassa, Ethiopia
| | - Bernt Lindtjørn
- Centre for International Health, University of Bergen, Bergen, Norway
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Carrasco-Escobar G, Gamboa D, Castro MC, Bangdiwala SI, Rodriguez H, Contreras-Mancilla J, Alava F, Speybroeck N, Lescano AG, Vinetz JM, Rosas-Aguirre A, Llanos-Cuentas A. Micro-epidemiology and spatial heterogeneity of P. vivax parasitaemia in riverine communities of the Peruvian Amazon: A multilevel analysis. Sci Rep 2017; 7:8082. [PMID: 28808240 PMCID: PMC5556029 DOI: 10.1038/s41598-017-07818-0] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 07/04/2017] [Indexed: 01/07/2023] Open
Abstract
Malaria has steadily increased in the Peruvian Amazon over the last five years. This study aimed to determine the parasite prevalence and micro-geographical heterogeneity of Plasmodium vivax parasitaemia in communities of the Peruvian Amazon. Four cross-sectional active case detection surveys were conducted between May and July 2015 in four riverine communities in Mazan district. Analysis of 2785 samples of 820 individuals nested within 154 households for Plasmodium parasitaemia was carried out using light microscopy and qPCR. The spatio-temporal distribution of Plasmodium parasitaemia, dominated by P. vivax, was shown to cluster at both household and community levels. Of enrolled individuals, 47% had at least one P. vivax parasitaemia and 10% P. falciparum, by qPCR, both of which were predominantly sub-microscopic and asymptomatic. Spatial analysis detected significant clustering in three communities. Our findings showed that communities at small-to-moderate spatial scales differed in P. vivax parasite prevalence, and multilevel Poisson regression models showed that such differences were influenced by factors such as age, education, and location of households within high-risk clusters, as well as factors linked to a local micro-geographic context, such as travel and occupation. Complex transmission patterns were found to be related to human mobility among communities in the same micro-basin.
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Affiliation(s)
- Gabriel Carrasco-Escobar
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacióny Desarrollo, Facultad de Cienciasy Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru.
- Facultad de Salud Públicay Administración, Universidad Peruana Cayetano Heredia, Lima, Peru.
| | - Dionicia Gamboa
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacióny Desarrollo, Facultad de Cienciasy Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
- Instituto de Medicina Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Ciencias Celularesy Moleculares, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Marcia C Castro
- Department of Global Health and Population, Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Shrikant I Bangdiwala
- Department of Biostatistics, University of North Carolina Gillings School of Global Public Health, Chapel Hill, NC, USA
- Department of Health Research Methods, Evidence and Impact, McMaster University, Hamilton, ON, Canada
| | | | - Juan Contreras-Mancilla
- Laboratorio ICEMR-Amazonia, Laboratorios de Investigacióny Desarrollo, Facultad de Cienciasy Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
| | | | - Niko Speybroeck
- Research Institute of Health and Society (IRSS), Université Catholique de Louvain, Brussels, Belgium
| | - Andres G Lescano
- Facultad de Salud Públicay Administración, Universidad Peruana Cayetano Heredia, Lima, Peru
| | - Joseph M Vinetz
- Instituto de Medicina Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
- Departamento de Ciencias Celularesy Moleculares, Facultad de Ciencias y Filosofia, Universidad Peruana Cayetano Heredia, Lima, Peru
- Division of Infectious Diseases, Department of Medicine, University of California San Diego School of Medicine, La Jolla, California, USA
| | - Angel Rosas-Aguirre
- Instituto de Medicina Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru
- Research Institute of Health and Society (IRSS), Université Catholique de Louvain, Brussels, Belgium
| | - Alejandro Llanos-Cuentas
- Facultad de Salud Públicay Administración, Universidad Peruana Cayetano Heredia, Lima, Peru.
- Instituto de Medicina Tropical "Alexander von Humboldt", Universidad Peruana Cayetano Heredia, Lima, Peru.
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Haile M, Lemma H, Weldu Y. Population Movement as a Risk Factor for Malaria Infection in High-Altitude Villages of Tahtay-Maychew District, Tigray, Northern Ethiopia: A Case-Control Study. Am J Trop Med Hyg 2017; 97:726-732. [PMID: 28722582 DOI: 10.4269/ajtmh.17-0129] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Key goal and targets of the Ethiopia National Malaria Control Program are to achieve malaria elimination within specific geographical areas with historically low malaria transmission and to reach near-zero malaria transmission in the remaining malarious areas by 2020. However, back and forth population movement between high-transmission and low-transmission area imposes challenge on the success of national malaria control programs. Therefore, examining the effect of human movement and identification of at-risk populations is crucial in an elimination setting. A matched case-control study was conducted among 520 study participants at a community level in low malaria transmission settings in northern Ethiopia. Study participants who received a malaria test were interviewed regarding their recent travel history. Bivariate and multivariate analyses were carried out to determine if the reported travel was related to malaria infection. Younger age (adjusted odds ratio [AOR] = 3.20, 95% confidence interval [CI]: 1.73, 5.89) and travel in the previous month (AOR = 11.40, 95% CI: 6.91, 18.82) were statistically significant risk factors for malaria infection. Other statistically significant factors, including lower educational level (AOR = 2.21, 95% CI: 1.26, 3.86) and nonagricultural in occupation (AOR = 2.0, 95% CI: 1.02, 3.94), were also found as risk factors for malaria infection. Generally, travel history was found to be a strong predictor for malaria acquisition in the high-altitude villages. Therefore, besides the existing efforts in endemic areas, targeting those who frequently travel to malarious areas is crucial to reduce malaria infection risks and possibility of local transmissions in high-altitude areas of northern Ethiopia.
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Affiliation(s)
- Mebrahtom Haile
- Federal Ministry of Health, Addis Ababa, Ethiopia.,School of Water and Public Health, Ethiopian Institute of Water Resource, Addis Ababa University, Ethiopia
| | - Hailemariam Lemma
- Public Health Department, College of Health Sciences, Mekelle University, Mekelle, Ethiopia.,Federal Ministry of Health, Addis Ababa, Ethiopia
| | - Yemane Weldu
- Department of Medical Microbiology and Immunology, Institute of Biomedical Sciences, College of Health Sciences, Mekelle University, Mekelle, Ethiopia
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Daygena TY, Massebo F, Lindtjørn B. Variation in species composition and infection rates of Anopheles mosquitoes at different altitudinal transects, and the risk of malaria in the highland of Dirashe Woreda, south Ethiopia. Parasit Vectors 2017; 10:343. [PMID: 28724450 PMCID: PMC5518156 DOI: 10.1186/s13071-017-2288-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 07/13/2017] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND The transmission of malaria is heterogeneous, and varies due to altitude. The information on whether the transmission of malaria is indigenous or imported to highland areas is scarce. Therefore, this study aimed to assess the species composition and infection rates of Anopheles at different altitudinal transects, and the risk of malaria if any in the highland of Dirashe Woreda, South Ethiopia. METHODS This study was conducted in Gato (low altitude; average elevation of 1273 m), Onota (mid-altitude; average elevation of 1707 m) and Layignaw-Arguba (high altitude; average elevation of 2337 m) from August 2015 to April 2016. Anopheles mosquitoes were sampled using Centers for Disease Control and Prevention (CDC) light traps from thirty houses (ten houses from each village). The circum-sporozoite proteins (CSPs) rate and entomological inoculation rate (EIR) of Anopheles mosquitoes were estimated. For the epidemiological survey, malaria cases were collected from laboratory registration books of selected health facilities from (August 2015-April 2016). A cross-sectional survey was done to collect data on malaria vector control activities in each village (August-September 2015). RESULTS One thousand two hundred sixty-eight Anopheles mosquitoes comprising Anopheles arabiensis, An. demeilloni, An. cinereus, An. pharoensis, An. funestus-group, An. pretoriensis, An. christyi, An. ardensis and An. tenebrosus were identified in the study area. Anopheles arabiensis was the dominant species in Gato, whereas An. demeilloni was the dominant species in Layignaw-Arguba. Five mosquitoes, three An. arabiensis from Gato and two An. demeilloni from Layignaw-Arguba, were positive for Plasmodium falciparum CSPs. Plasmodium falciparum CSP rate was 0.4% (95% CI: 0.08-1.15) for An. arabiensis in Gato, and it was 0.64% (95% CI: 0.08-2.3) for An. demeilloni from Layignaw-Arguba. The P. falciparum EIR of An. arabiensis was 8.6 (95% CI: 2.4-33.4) infectious bites/person/nine-months in Gato. Plasmodium falciparum parasite was dominant in Gato (88%) and Onota (57.5%), whereas in Layignaw-Arguba P. vivax (59.4%) occurred most frequently. Increased malaria cases were observed in children age 5-14 years in Gato (P < 0.05), whereas in Onota and Layignaw-Arguba there was no statistically significant difference in malaria cases among the age groups. Households owning at least one long lasting insecticidal net were 92.7% in the study area, and 77.6% slept under the net during the preceding night of the survey. About 64.4% of the households in Gato were protected by the indoor residual spray. However, the spraying was done when the density of local malaria vectors was low. CONCLUSION Incrimination of Plasmodium CSP positive Anopheles species and the presence of malaria in children under five years in high altitude Layignaw-Arguba may justify the existence of indigenous malaria transmission and the need for effective malaria control. Further investigation and confirmation using more sensitive molecular techniques are however needed to consider An. demeilloni as a proven vector of malaria in Ethiopia.
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Affiliation(s)
- Taye Yohannes Daygena
- Department of Biology, Arba Minch University, Arba Minch, Ethiopia
- Dirashe Woreda Health Office, Malaria and Other Vector-Borne Diseases Control Unit, Gidole, Ethiopia
| | - Fekadu Massebo
- Department of Biology, Arba Minch University, Arba Minch, Ethiopia
| | - Bernt Lindtjørn
- Centre for International Health, University of Bergen, Bergen, Norway
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Omondi CJ, Onguru D, Kamau L, Nanyingi M, Ong'amo G, Estambale B. Perennial transmission of malaria in the low altitude areas of Baringo County, Kenya. Malar J 2017. [PMID: 28623926 PMCID: PMC5474045 DOI: 10.1186/s12936-017-1904-y] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria causes the greatest public health burden in sub-Saharan Africa where high mortality occurs mainly in children under 5 years of age. Traditionally, malaria has been reported mainly in the lowlands endemic regions of western Kenya, while the highlands of the Rift Valley have been relatively free except for the sporadic epidemics in some areas. Baringo County is located in the Kenyan highlands. The county generally experiences seasonal transmission of malaria. A few hotspots which experience continuous malaria transmission in the county do however exist. The objective of this study was to assess malaria infection status and identify areas with continuous transmissions with a view to mapping out probable transmission hot spots useful in mounting focused interventions within the county. METHODS Systematic sampling was employed to identify 1668 primary school pupils from fifteen primary schools located in 4 ecological zones (lowland, midland, highland and riverine) of three sub-counties of Baringo. Finger prick blood sampling was done every 4 months (during the dry season in February/March, after the long rains in June/July and short rains in November 2015). Malaria occurrence was tested using rapid diagnostic test kit (CareStart HRP-2 Pf). Microscopic examination was done on all RDT positive and 10% of negative cases. RESULTS A total of 268 (16.1%), out of 1668 pupils tested positive for Plasmodium falciparum by RDT; 78% had a single episode, 16.8% had 2 episodes, 4.9% had 3 episodes and 0.4% had 4 episodes. The riverine zone had the highest malaria cases (23.2%) followed by lowlands (0.9%). No malaria cases were detected in the midland zone while highland zone recorded only few cases during the third follow up. Up to 10.7% of malaria cases were reported in the dry season, 2.9% during the long rains and 5.7% in short rains season. CONCLUSIONS Malaria infection was prevalent in Baringo County and was mainly restricted to the riverine zone where transmission is continuous throughout the year. High malaria prevalence occurred in the dry season compared to the wet season. Even though malaria transmission is relatively low compared to endemic regions of Kenya, there is a need for continued monitoring of transmission dynamics under changing climatic conditions as well as establishing expanded malaria control strategies especially within the riverine zone which would include an integrated mosquito control and chemotherapy for infected individuals.
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Affiliation(s)
- Collince J Omondi
- Department of Zoological Sciences, Kenyatta University, P.O. Box 43844, Nairobi, 00100, Kenya
| | - Daniel Onguru
- School of Health Sciences, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, 40601, Kenya.
| | - Lucy Kamau
- Department of Zoological Sciences, Kenyatta University, P.O. Box 43844, Nairobi, 00100, Kenya
| | - Mark Nanyingi
- Department of Public Health, Pharmacology and Toxicology, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - George Ong'amo
- School of Biological Sciences, University of Nairobi, P.O. Box 30197, Nairobi, 00100, Kenya
| | - Benson Estambale
- School of Health Sciences, Jaramogi Oginga Odinga University of Science and Technology, P.O. Box 210, Bondo, 40601, Kenya
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Defining micro-epidemiology for malaria elimination: systematic review and meta-analysis. Malar J 2017; 16:164. [PMID: 28427389 PMCID: PMC5399382 DOI: 10.1186/s12936-017-1792-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Accepted: 03/28/2017] [Indexed: 11/24/2022] Open
Abstract
Background Malaria risk can vary markedly between households in the same village, or between villages, but the determinants of this “micro-epidemiological” variation in malaria risk remain poorly understood. This study aimed to identify factors that explain fine-scale variation in malaria risk across settings and improve definitions and methods for malaria micro-epidemiology. Methods A systematic review of studies that examined risk factors for variation in malaria infection between individuals, households, clusters, hotspots, or villages in any malaria-endemic setting was conducted. Four databases were searched for studies published up until 6th October 2015. Crude and adjusted effect estimates for risk factors for malaria infection were combined in random effects meta-analyses. Bias was assessed using the Newcastle–Ottawa Quality Assessment Scale. Results From 743 retrieved records, 51 studies were selected, representing populations comprising over 160,000 individuals in 21 countries, in high- and low-endemicity settings. Sixty-five risk factors were identified and meta-analyses were conducted for 11 risk factors. Most studies focused on environmental factors, especially increasing distance from a breeding site (OR 0.89, 95% CI 0.86–0.92, 10 studies). Individual bed net use was protective (OR 0.63, 95% CI 0.52–0.77, 12 studies), but not household bed net ownership. Increasing household size (OR 1.08, 95% CI 1.01–1.15, 4 studies) and household crowding (OR 1.79, 95% CI 1.48–2.16, 4 studies) were associated with malaria infection. Health seeking behaviour, medical history and genetic traits were less frequently studied. Only six studies examined whether individual-level risk factors explained differences in malaria risk at village or hotspot level, and five studies reported different risk factors at different levels of analysis. The risk of bias varied from low to high in individual studies. Insufficient reporting and comparability of measurements limited the number of meta-analyses conducted. Conclusions Several variables associated with individual-level malaria infection were identified, but there was limited evidence that these factors explain variation in malaria risk at village or hotspot level. Social, population and other factors may confound estimates of environmental risk factors, yet these variables are not included in many studies. A structured framework of malaria risk factors is proposed to improve study design and quality of evidence in future micro-epidemiological studies. Electronic supplementary material The online version of this article (doi:10.1186/s12936-017-1792-1) contains supplementary material, which is available to authorized users.
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Assessing the Risk Factors Associated with Malaria in the Highlands of Ethiopia: What Do We Need to Know? Trop Med Infect Dis 2017; 2:tropicalmed2010004. [PMID: 30270863 PMCID: PMC6082051 DOI: 10.3390/tropicalmed2010004] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2016] [Revised: 02/23/2017] [Accepted: 02/25/2017] [Indexed: 12/13/2022] Open
Abstract
Malaria has been Ethiopia's predominant communicable disease for decades. Following the catastrophic malaria outbreak in 2003⁻2004, the Federal Ministry of Health (FMoH) took drastic public health actions to lower the burden of malaria. The FMoH achieved significant declines in malaria mortality and incidence, and recently declared its objective to achieve malaria elimination in low malaria transmission areas of Ethiopia by 2020. However, while the overall malaria prevalence has decreased, unpredictable outbreaks increasingly occur irregularly in regions previously considered "malaria-free". Such outbreaks have disastrous consequences on populations of these regions as they have no immunity against malaria. The Amhara Region accounts for 31% of Ethiopia's malaria burden and is targeted for malaria elimination by the FMoH. Amhara's epidemiological surveillance system faces many challenges to detect in a timely manner the unpredictable and irregular malaria outbreaks that occur in areas of otherwise low transmission. Despite the evidence of a shift in malaria transmission patterns, Amhara's malaria control interventions remain constrained to areas that are historically known to have stable malaria transmission. This paper discusses the influence of temperature and precipitation variability, entomological parameters, and human population mobility on malaria transmission patterns across the Amhara Region, and in particular, in areas of unstable transmission. We argue that malaria epidemiological surveillance systems can be improved by accounting for population movements in addition to environmental and entomological factors. However, to date, no study has statistically analyzed the interplay of population dynamics on environmental and entomological drivers of malaria transmission.
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Roberts D, Matthews G. Risk factors of malaria in children under the age of five years old in Uganda. Malar J 2016; 15:246. [PMID: 27121122 PMCID: PMC4848810 DOI: 10.1186/s12936-016-1290-x] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 04/13/2016] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria is the leading cause of morbidity in Uganda with 90-95 % of the population at risk and it contributing to approximately 13 % of under-five mortality. The aim of this study was to investigate the relationship between the malaria status of children under the age of 5 years old in Uganda and selected socio-economic, demographic and environmental factors, as well as to identify significant risk factors associated with malaria. METHODS This study made use of data collected from the 2014 Malaria Indicator Survey conducted in Uganda. Two test procedures for malaria in children under the age of 5 years old were carried out. Due to the complex survey design, a generalized linear mixed model was used to test for associations between several independent variables and the response variable, which was whether a child tested positive or negative for malaria according to the microscopy test. RESULTS The sample in this study was made up of 4939 children. Of those children, 974 tested positive for malaria, resulting in an observed malaria prevalence of 19.7 %. The socio-economic factors closely related to the risk of malaria were main floor material, main wall material and availability of electricity in the household. The event of indoor residual spraying (IRS) significantly reduced a child's risk of malaria. An older child was associated with a higher risk of malaria, however their risk decreased with an increase in cluster altitude and an increase in their caregiver's education level. CONCLUSION Although there has been a significant increase in the use of mosquito nets since the previous Malaria Indicator Survey done in 2009, particularly in the use of insecticide-treated nets (ITNs) and long-lasting insecticidal nets (LLINs), these control measures alone may not be sufficient. IRS will be a key strategy in reaching the malaria goals set by the government of Uganda. Supplementing these control measures with education of appropriate and consistent use of ITNs and LLINs, as well as education of practicing safe living habits, such as reducing outdoor activities during peak biting hours of a mosquito, can go a long way in aiding the reduction of the burden of malaria in Uganda.
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Affiliation(s)
- Danielle Roberts
- School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Westville, Private Bag X 54001, 4000, Durban, South Africa.
| | - Glenda Matthews
- School of Mathematics, Statistics and Computer Science, University of KwaZulu-Natal, Westville, Private Bag X 54001, 4000, Durban, South Africa
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Lynch CA, Cook J, Nanyunja S, Bruce J, Bhasin A, Drakeley C, Roper C, Pearce R, Rwakimari JB, Abeku TA, Corran P, Cox J. Application of Serological Tools and Spatial Analysis to Investigate Malaria Transmission Dynamics in Highland Areas of Southwest Uganda. Am J Trop Med Hyg 2016; 94:1251-1258. [PMID: 27022156 PMCID: PMC4889741 DOI: 10.4269/ajtmh.15-0653] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2015] [Accepted: 03/03/2016] [Indexed: 11/28/2022] Open
Abstract
Serological markers, combined with spatial analysis, offer a comparatively more sensitive means by which to measure and detect foci of malaria transmission in highland areas than traditional malariometric indicators. Plasmodium falciparum parasite prevalence, seroprevalence, and seroconversion rate to P. falciparum merozoite surface protein-119 (MSP-119) were measured in a cross-sectional survey to determine differences in transmission between altitudinal strata. Clusters of P. falciparum parasite prevalence and high antibody responses to MSP-119 were detected and compared. Results show that P. falciparum prevalence and seroprevalence generally decreased with increasing altitude. However, transmission was heterogeneous with hotspots of prevalence and/or seroprevalence detected in both highland and highland fringe altitudes, including a serological hotspot at 2,200 m. Results demonstrate that seroprevalence can be used as an additional tool to identify hotspots of malaria transmission that might be difficult to detect using traditional cross-sectional parasite surveys or through vector studies. Our study findings identify ways in which malaria prevention and control can be more effectively targeted in highland or low transmission areas via serological measures. These tools will become increasingly important for countries with an elimination agenda and/or where malaria transmission is becoming patchy and focal, but receptivity to malaria transmission remains high.
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Affiliation(s)
- Caroline A. Lynch
- *Address correspondence to Caroline A. Lynch, London School of Hygiene and Tropical Medicine, G14a, Keppel Street, London, WC1E 7HT, United Kingdom. E-mail:
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Ayalew S, Mamo H, Animut A, Erko B. Assessment of Current Malaria Status in Light of the Ongoing Control Interventions, Socio-Demographic and Environmental Variables in Jiga Area, Northwest Ethiopia. PLoS One 2016; 11:e0146214. [PMID: 26751687 PMCID: PMC4709195 DOI: 10.1371/journal.pone.0146214] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2014] [Accepted: 12/15/2015] [Indexed: 11/25/2022] Open
Abstract
Following substantial decline in malaria burden in Ethiopia, the country is planning to eliminate malaria in certain low transmission settings by 2020. To evaluate the attainability of this goal in-depth examination of malaria parasite carriage at community level is necessary. This study was, therefore, aimed at assessing the current situation of malaria in relation to ongoing control interventions in Jiga area, Jabi Tehnan District in northwest Ethiopia. A cross-sectional household (HH) survey was conducted in November-December 2013. Out of 2,574 HHs (11,815 people) in the entire Jabi Tehnan District, 392 (accommodating 1911 people) were randomly selected from three purposely selected villages. One randomly selected member from each selected HH was tested for malaria using rapid diagnostic test (mRDT). All participants tested for malaria (n = 392) were afebrile (axillary temperature <37.5°C). Eleven individuals (2.8%, 95% confidence interval (CI):1.2–4.4%) were found to be mRDT positive. Most HHs (95.9%, 95% CI: 93.5–97.5%) had at least 1 long-lasting insecticidal net (LLIN). Insecticide residual spraying (IRS) coverage the last six months was 85.5% (95% CI: 82.0–88.9%). Malaria prevalence remains unexpectedly high despite high HH coverage of control interventions.
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Affiliation(s)
- Seble Ayalew
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
| | - Hassen Mamo
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
| | - Abebe Animut
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
| | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
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Yimer F, Animut A, Erko B, Mamo H. Past five-year trend, current prevalence and household knowledge, attitude and practice of malaria in Abeshge, south-central Ethiopia. Malar J 2015; 14:230. [PMID: 26037129 PMCID: PMC4464226 DOI: 10.1186/s12936-015-0749-5] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2015] [Accepted: 05/26/2015] [Indexed: 11/12/2022] Open
Abstract
Background In Ethiopia malaria remains a leading cause of outpatient consultation despite massive control efforts. This study was aimed at analysing 5-year retrospective trend and current prevalence of malaria as well as community knowledge, attitude and practice (KAP) in Walga Health Centre (WHC) catchment area in Abeshge District, south-central Ethiopia. Methods A cross-sectional, household survey was conducted to determine malaria prevalence and KAP in December 2013. Further, malaria cases reported from WHC in 2008–2012 were extracted. A multi-stage, random sampling technique was used to select study participants from four kebeles. Of 800 participants, 400 were interviewed to assess their KAP about malaria and the other half were recruited for malaria microscopy. Results Overall, 11,523 (33.8 %) slide-confirmed malaria cases were reported (no fatalities) among 34,060 outpatients diagnosed in 2008–2012. There was successively significant decline in malaria prevalence from 2009 onwards although a significant rise was noticed in 2009 compared to 2008 (p <0.0001). Male malaria suspects (17,626) were significantly higher than of females (16,434) (p = 0.0127) but malaria prevalence was not significantly variable between sexes. Individuals who were ≥15 years constituted 44.9 % of the patients. Although most participants (78.8 %) associated mosquito bites with malaria, the remaining mentioned exposure to rain or body contact with malaria patients as causes of malaria. Mosquito nets, draining stagnant water and indoor residual spraying were the most frequently mentioned malaria preventive measures. In the parasitological survey, a single individual (0.25 %) with mixed Plasmodium falciparum-Plasmodium vivax infections was found. Conclusion Although malaria remains a primary cause of outpatient admission in WHC, the retrospective data showed a significantly declining trend. This together with the very low prevalence in the current parasitological survey suggests the effectiveness of ongoing control interventions in the locality.
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Affiliation(s)
- Fisseha Yimer
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, PO Box 1176, Addis Ababa, Ethiopia.
| | - Abebe Animut
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, PO Box 1176, Addis Ababa, Ethiopia.
| | - Berhanu Erko
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, PO Box 1176, Addis Ababa, Ethiopia.
| | - Hassen Mamo
- Department of Microbial, Cellular and Molecular Biology, College of Natural Sciences, Addis Ababa University, PO Box 1176, Addis Ababa, Ethiopia.
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Degefa T, Zeynudin A, Godesso A, Michael YH, Eba K, Zemene E, Emana D, Birlie B, Tushune K, Yewhalaw D. Malaria incidence and assessment of entomological indices among resettled communities in Ethiopia: a longitudinal study. Malar J 2015; 14:24. [PMID: 25626598 PMCID: PMC4318213 DOI: 10.1186/s12936-014-0532-z] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2014] [Accepted: 12/22/2014] [Indexed: 11/10/2022] Open
Abstract
Background Population resettlement has been considered among factors that may increase risk of malaria transmission. This study reports, the impact of resettlement on malaria incidence and entomological indices among communities resettled in suburbs of Jimma town, southwestern Ethiopia. Methods A cohort of 604 study participants (302 resettlers and 302 non-resettlers) was monthly followed-up from September to November 2013 using active case detection. Moreover, longitudinal entomological study was conducted from June to November 2013. Anopheline mosquitoes were collected using CDC light traps and pyrethrum spray catches. Sporozoite ELISA was performed to determine Plasmodium infection rates. Results Overall, 112 malaria cases were recorded during the three-month follow-up, of which 74.1% of the cases were from resettlement villages. Plasmodium falciparum incidence from resettlement and non-resettlement villages was 52.5 and 14.5/1,000 person-months at risk, respectively. Resettlement villages were three times at higher risk of Plasmodium infection (OR = 2.8, 95% CI: 1.22-6.48). Anopheles gambiae s.l. was the predominant (86.6%) of all the collected anopheline mosquito species. Plasmodium sporozoite rate in the resettlement and non-resettlement villages was 2.1 and 0.72%, respectively. Plasmodium falciparum entomological inoculation rate (EIR) for An. gambiae s.l. in the resettlement and non-resettlement villages was 13.1 and 0 infective bites/person/night, respectively. Both sporozoite rate and EIR were significantly higher in the resettlement villages (p < 0.05). Conclusion Resettled communities were at higher risk of malaria infection as compared to non-resettled communities. Special attention should be given to malaria control interventions during resettlement programmes.
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Affiliation(s)
- Teshome Degefa
- Department of Medical Laboratory Sciences and Pathology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Ahmed Zeynudin
- Department of Medical Laboratory Sciences and Pathology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Ameyu Godesso
- Department of Sociology, College of Social Sciences, Jimma University, Jimma, Ethiopia.
| | - Yohannes Haile Michael
- Department of Health Services Management, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Kasahun Eba
- Department of Environmental Health and Technology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Endalew Zemene
- Department of Medical Laboratory Sciences and Pathology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Daniel Emana
- Department of Medical Laboratory Sciences and Pathology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Belay Birlie
- Department of Statistics, College of Natural Sciences, Jimma University, Jimma, Ethiopia.
| | - Kora Tushune
- Department of Health Services Management, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
| | - Delenasaw Yewhalaw
- Department of Medical Laboratory Sciences and Pathology, College of Public Health and Medical Sciences, Jimma University, Jimma, Ethiopia.
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Kateera F, Mens PF, Hakizimana E, Ingabire CM, Muragijemariya L, Karinda P, Grobusch MP, Mutesa L, van Vugt M. Malaria parasite carriage and risk determinants in a rural population: a malariometric survey in Rwanda. Malar J 2015; 14:16. [PMID: 25604040 PMCID: PMC4308829 DOI: 10.1186/s12936-014-0534-x] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2014] [Accepted: 12/27/2014] [Indexed: 01/05/2023] Open
Abstract
Background Based on routine health facility case data, Rwanda has achieved a significant malaria burden reduction in the past ten years. However, community-based malaria parasitaemia burden and reasons for continued residual infections, despite a high coverage of control interventions, have yet to be characterized. Measurement of malaria parasitaemia rates and evaluation of associated risk factors among asymptomatic household members in a rural community in Rwanda were conducted. Methods A malariometric household survey was conducted between June and November 2013, involving 12,965 persons living in 3,989 households located in 35 villages in a sector in eastern Rwanda. Screening for malaria parasite carriage and collection of demographic, socio-economic, house structural features, and prior fever management data, were performed. Logistic regression models with adjustment for within- and between-households clustering were used to assess malaria parasitaemia risk determinants. Results Overall, malaria parasitaemia was found in 652 (5%) individuals, with 518 (13%) of households having at least one parasitaemic member. High malaria parasite carriage risk was associated with being male, child or adolescent (age group 4–15), reported history of fever and living in a household with multiple occupants. A malaria parasite carriage risk-protective effect was associated with living in households of, higher socio-economic status, where the head of household was educated and where the house floor or walls were made of cement/bricks rather than mud/earth/wood materials. Parasitaemia cases were found to significantly cluster in the Gikundamvura area that neighbours marshlands. Conclusion Overall, Ruhuha Sector can be classified as hypo-endemic, albeit with a particular ‘cell of villages’ posing a higher risk for malaria parasitaemia than others. Efforts to further reduce transmission and eventually eliminate malaria locally should focus on investments in programmes that improve house structure features (that limit indoor malaria transmission), making insecticide-treated bed nets and indoor residual spraying implementation more effective.
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Affiliation(s)
- Fredrick Kateera
- Centre of Tropical Medicine and Travel Medicine, Department of Infectious Diseases, Division of Internal Medicine, Academic Medical Centre, Meibergdreef 9, Amsterdam, 1100 DE, The Netherlands.
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Ngom R, Siegmund A. The key role of socio-demographic and socio-environmental factors in urban malaria occurrence and control - An illustration using the city of Yaoundé. Soc Sci Med 2014; 133:269-79. [PMID: 25498155 DOI: 10.1016/j.socscimed.2014.12.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Cities in developing countries are experiencing an unprecedented population growth that illustrates a demographic transition and a shift towards modernization with consequences on their epidemiological profiles. However, this change is characterized by an important rural-to-urban social and cultural transfer that can bias the expected epidemiological transition; at the same time, this transfer renders the understanding of the occurrence of communicable diseases more complex than it appears. Urban malaria occurrence was modeled for the city of Yaoundé in Cameroon. Retrospective interviews were conducted to describe a variety of epidemiological, social and environmental variables at the household level. Various ecological variables originating from remote sensing data were also integrated. Multivariate multilevel negative binomial analyses were developed to evaluate the distinct contributions of explanatory social and ecological variables. Spatial models based on the level of urbanity were implemented to understand the intelligence of urban malaria as characterized by those variables. The results showed an overall higher statistical importance of socio-environmental variables, particularly those describing rural origin socio-cultural features in terms of non-conventional housing types and urban agriculture (UA). The spatial patterns of the urban malaria occurrences displayed a complex combination of population density gradients and socio-environmental factors, illustrating the importance of conventional urban features over rural/non-conventional features in reducing the occurrence of urban malaria.
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Affiliation(s)
- Roland Ngom
- Centre Eau terre Environnment, Institut National de la Recherche Scientifique Québec, Canada.
| | - Alexander Siegmund
- Department of Geography, Research Group for Earth Observation (rgeo), University of Education, Heidelberg, Germany
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Midekisa A, Senay GB, Wimberly MC. Multisensor earth observations to characterize wetlands and malaria epidemiology in Ethiopia. WATER RESOURCES RESEARCH 2014; 50:8791-8806. [PMID: 25653462 PMCID: PMC4303930 DOI: 10.1002/2014wr015634] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2014] [Accepted: 10/08/2014] [Indexed: 05/14/2023]
Abstract
Malaria is a major global public health problem, particularly in Sub-Saharan Africa. The spatial heterogeneity of malaria can be affected by factors such as hydrological processes, physiography, and land cover patterns. Tropical wetlands, for example, are important hydrological features that can serve as mosquito breeding habitats. Mapping and monitoring of wetlands using satellite remote sensing can thus help to target interventions aimed at reducing malaria transmission. The objective of this study was to map wetlands and other major land cover types in the Amhara region of Ethiopia and to analyze district-level associations of malaria and wetlands across the region. We evaluated three random forests classification models using remotely sensed topographic and spectral data based on Shuttle Radar Topographic Mission (SRTM) and Landsat TM/ETM+ imagery, respectively. The model that integrated data from both sensors yielded more accurate land cover classification than single-sensor models. The resulting map of wetlands and other major land cover classes had an overall accuracy of 93.5%. Topographic indices and subpixel level fractional cover indices contributed most strongly to the land cover classification. Further, we found strong spatial associations of percent area of wetlands with malaria cases at the district level across the dry, wet, and fall seasons. Overall, our study provided the most extensive map of wetlands for the Amhara region and documented spatiotemporal associations of wetlands and malaria risk at a broad regional level. These findings can assist public health personnel in developing strategies to effectively control and eliminate malaria in the region. KEY POINTS Remote sensing produced an accurate wetland map for the Ethiopian highlandsWetlands were associated with spatial variability in malaria riskMapping and monitoring wetlands can improve malaria spatial decision support.
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Affiliation(s)
- Alemayehu Midekisa
- Geospatial Sciences Center of Excellence, South Dakota State University Brookings, South Dakota, USA
| | - Gabriel B Senay
- U.S. Geological Survey Earth Resources Observation and Science Center Sioux Falls, South Dakota, USA
| | - Michael C Wimberly
- Geospatial Sciences Center of Excellence, South Dakota State University Brookings, South Dakota, USA
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Dræbel T, Gueth Kueil B. Lay perceptions of malaria and therapeutic itinerary of resettled pregnant women in South Sudan. Int Health 2014; 6:317-21. [PMID: 25091025 DOI: 10.1093/inthealth/ihu047] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Approximately 95% of South Sudan is malaria-endemic and transmission is high throughout the year. Annually, 2.3 million people are at risk of malarial infection, but children under 5 years, pregnant women and their unborn children are particularly at high risk. Appropriate policies for malarial prevention and control require a better understanding of the populations' malarial perceptions and treatment itinerary. METHODS A qualitative study was carried out to explore malarial lay perceptions and therapeutic itinerary among 30 resettled pregnant women in Unity State, South Sudan. RESULTS The study showed that the therapeutic itinerary was prompted by fever and composed of five steps that were simultaneously or successively explored. The household and community constitute the first-line treatment options for fever. Interviewees relied on homemade remedies and concoctions, traditional healers' cures, magician's rituals and private formal and informal medicine vendors at the local market before seeking malarial diagnosis and treatment at the health centre. CONCLUSIONS Improving capacities for proper identification and management of malarial fever at household and community level is a priority for reducing the delay in seeking timely and proper treatment. The formal health system may, in time, aspire to address the economic and cultural barriers within the system that contribute to delaying effective treatment-seeking.
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Affiliation(s)
- Tania Dræbel
- Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - Bill Gueth Kueil
- Ministry of Health, South Sudan and Care International, Bentiu, Unity, South Sudan
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Alemu K, Worku A, Berhane Y, Kumie A. Spatiotemporal clusters of malaria cases at village level, northwest Ethiopia. Malar J 2014; 13:223. [PMID: 24903061 PMCID: PMC4072611 DOI: 10.1186/1475-2875-13-223] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Accepted: 05/28/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria attacks are not evenly distributed in space and time. In highland areas with low endemicity, malaria transmission is highly variable and malaria acquisition risk for individuals is unevenly distributed even within a neighbourhood. Characterizing the spatiotemporal distribution of malaria cases in high-altitude villages is necessary to prioritize the risk areas and facilitate interventions. METHODS Spatial scan statistics using the Bernoulli method were employed to identify spatial and temporal clusters of malaria in high-altitude villages. Daily malaria data were collected, using a passive surveillance system, from patients visiting local health facilities. Georeference data were collected at villages using hand-held global positioning system devices and linked to patient data. Bernoulli model using Bayesian approaches and Marcov Chain Monte Carlo (MCMC) methods were used to identify the effects of factors on spatial clusters of malaria cases. The deviance information criterion (DIC) was used to assess the goodness-of-fit of the different models. The smaller the DIC, the better the model fit. RESULTS Malaria cases were clustered in both space and time in high-altitude villages. Spatial scan statistics identified a total of 56 spatial clusters of malaria in high-altitude villages. Of these, 39 were the most likely clusters (LLR = 15.62, p < 0.00001) and 17 were secondary clusters (LLR = 7.05, p < 0.03). The significant most likely temporal malaria clusters were detected between August and December (LLR = 17.87, p < 0.001). Travel away home, males and age above 15 years had statistically significant effect on malaria clusters at high-altitude villages. CONCLUSION The study identified spatial clusters of malaria cases occurring at high elevation villages within the district. A patient who travelled away from home to a malaria-endemic area might be the most probable source of malaria infection in a high-altitude village. Malaria interventions in high altitude villages should address factors associated with malaria clustering.
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Affiliation(s)
- Kassahun Alemu
- Department of Environmental and Occupational Health and Safety, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia.
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Men traveling away from home are more likely to bring malaria into high altitude villages, northwest Ethiopia. PLoS One 2014; 9:e95341. [PMID: 24748159 PMCID: PMC3991686 DOI: 10.1371/journal.pone.0095341] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2013] [Accepted: 03/25/2014] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Information about malaria risk factors at high altitudes is scanty. Understanding the risk factors that determine the risk of malaria transmission at high altitude villages is important to facilitate implementing sustainable malaria control and prevention programs. METHODS An unmatched case control study was conducted among patients seeking treatment at health centers in high altitude areas. Either microscopy or rapid diagnostic tests were used to confirm the presence of plasmodium species. A generalized linear model was used to identify the predictors of malaria transmission in high altitude villages. RESULTS Males (AOR = 3.11, 95%CI: 2.28, 4.23), and those who traveled away from the home in the previous month (AOR = 2.01, 95% CI: 1.56, 2.58) were strongly associated with presence of malaria in high altitude villages. Other significant factors, including agriculture in occupation (AOR = 1.41, 95% CI: 1.05, 1.93), plants used for fencing (AOR = 1.70, 95% CI: 1.18, 2.52) and forests near the house (AOR = 1.60, 95% CI: 1.15, 2.47), were found predictors for malaria in high altitude villages. CONCLUSION Travel outside of their home was an important risk of malaria infections acquisition. Targeting males who frequently travel to malarious areas can reduce malaria transmission risks in high altitude areas.
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Reithinger R, Ngondi J, Graves P, Hwang J, Getachew A, Jima D. Risk factors for anemia in children under 6 years of age in Ethiopia: analysis of the data from the cross-sectional Malaria IndicatorSurvey, 2007. Trans R Soc Trop Med Hyg 2013; 107:769-76. [PMID: 24218415 PMCID: PMC10563508 DOI: 10.1093/trstmh/trt096] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Malaria is a leading cause of morbidity in Ethiopia. However, its transmission varies in both space and time, and large areas of the country are hypoendemic and epidemic-prone. The Ethiopia National Malaria Indicator Survey 2007 is a cross-sectional, nationally-representative household survey. The objective of the analyses presented here were to use the survey's data to identify factors associated with anemia presence in children under 6 years of age (U6); specifically, investigate the association between malaria and anemia; and discuss using anemia as a malaria proxy biomarker in the Ethiopian hypo-endemic transmission setting. METHODS The survey sampled 4185 households in 347 enumeration areas ≤2500 m above sea level. Primary outcome was increasing anemia severity in sampled children: no anemia (Hb: ≥11g/dl); mild anemia (Hb: ≥8g/dl and <11g/dl); and moderate-severe anemia (Hb: <8g/dl). Secondary outcomes were positive malaria rapid diagnostic test (RDT) or blood slide microscopy. RESULTS The analysis included 6054 (92.0%) children U6 in 3962 households. The proportion of children with no anemia, mild anemia, and moderate-severe anemia was 63.6%, 31.3%, and 5.1%, respectively. The overall prevalence of anemia (Hb <11g/dl) was 36.4% (95% CI 34.4-38.4). Factors independently associated with reduced relative odds of anemia categories were age (OR=0.7, 95% CI 0.7-0.7) and female sex (OR=0.9, 95% CI 0.8-1.0); malaria RDT positivity was associated with increased relative odds of a more severe anemia category (OR=5.8, 95% CI 3.7-9.2). CONCLUSIONS We conclude that at altitudes ≤2500 m malaria appears to be a significant risk factor for anemia; potentially anemia could be used as a useful proxy biomarker for malaria and its control in Ethiopia.
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Affiliation(s)
- R. Reithinger
- U.S. Agency for International Development, Addis Ababa, Ethiopia
- RTI International, Washington, DC, USA
| | - J.M. Ngondi
- Department of Public Health and Primary Care, Institute of Public Health, University of Cambridge, Cambridge, UK
- RTI International, Dar-es-Salaam, Tanzania
- The Carter Center, Atlanta, GA, USA
| | - P.M. Graves
- The Carter Center, Atlanta, GA, USA
- School of Public Health, Tropical Medicine & Rehabilitation Sciences, James Cook University, Australia
| | - J. Hwang
- U.S. Centers for Disease Control and Prevention, Atlanta, GA, USA
- Global Health Group, University of California San Francisco, CA, USA
| | - A. Getachew
- Malaria Control and Evaluation Partnership in Africa (MACEPA), PATH, Addis Ababa, Ethiopia
| | - D. Jima
- Federal Ministry of Health, Addis Ababa, Ethiopia
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de Oliveira EC, dos Santos ES, Zeilhofer P, Souza-Santos R, Atanaka-Santos M. Geographic information systems and logistic regression for high-resolution malaria risk mapping in a rural settlement of the southern Brazilian Amazon. Malar J 2013; 12:420. [PMID: 24237621 PMCID: PMC3842636 DOI: 10.1186/1475-2875-12-420] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2013] [Accepted: 11/04/2013] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND In Brazil, 99% of the cases of malaria are concentrated in the Amazon region, with high level of transmission. The objectives of the study were to use geographic information systems (GIS) analysis and logistic regression as a tool to identify and analyse the relative likelihood and its socio-environmental determinants of malaria infection in the Vale do Amanhecer rural settlement, Brazil. METHODS A GIS database of georeferenced malaria cases, recorded in 2005, and multiple explanatory data layers was built, based on a multispectral Landsat 5 TM image, digital map of the settlement blocks and a SRTM digital elevation model. Satellite imagery was used to map the spatial patterns of land use and cover (LUC) and to derive spectral indices of vegetation density (NDVI) and soil/vegetation humidity (VSHI). An Euclidian distance operator was applied to measure proximity of domiciles to potential mosquito breeding habitats and gold mining areas. The malaria risk model was generated by multiple logistic regression, in which environmental factors were considered as independent variables and the number of cases, binarized by a threshold value was the dependent variable. RESULTS Out of a total of 336 cases of malaria, 133 positive slides were from inhabitants at Road 08, which corresponds to 37.60% of the notifications. The southern region of the settlement presented 276 cases and a greater number of domiciles in which more than ten cases/home were notified. From these, 102 (30.36%) cases were caused by Plasmodium falciparum and 174 (51.79%) cases by Plasmodium vivax. Malaria risk is the highest in the south of the settlement, associated with proximity to gold mining sites, intense land use, high levels of soil/vegetation humidity and low vegetation density. CONCLUSIONS Mid-resolution, remote sensing data and GIS-derived distance measures can be successfully combined with digital maps of the housing location of (non-) infected inhabitants to predict relative likelihood of disease infection through the analysis by logistic regression. Obtained findings on the relation between malaria cases and environmental factors should be applied in the future for land use planning in rural settlements in the Southern Amazon to minimize risks of disease transmission.
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Affiliation(s)
- Elaine Cristina de Oliveira
- Epidemiological Surveillance, Health Secretary of Mato Grosso, Rua D, Political Administrative Center, Cuiabá, Mato Grosso State 78.050-970, Brazil
| | - Emerson Soares dos Santos
- Department of Geography, Federal University of Mato Grosso, Av. Fernando Corrêa, Cuiabá, Mato Grosso State 78.060-900, Brazil
| | - Peter Zeilhofer
- Department of Geography, Federal University of Mato Grosso, Av. Fernando Corrêa, Cuiabá, Mato Grosso State 78.060-900, Brazil
| | - Reinaldo Souza-Santos
- Department of Endemic Disease, Brazilian National School of Public Health, Oswaldo Cruz Foundation, Rua Leopoldo Bulhões, 1480, Rio de Janeiro, Rio de Janeiro State 21.041-210, Brazil
| | - Marina Atanaka-Santos
- Institute of Public Health, Federal University of Mato Grosso, Av. Fernando Corrêa, Cuiabá, Mato Grosso State 78.060-900, Brazil
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Integrated approach to malaria prevention at household level in rural communities in Uganda: experiences from a pilot project. Malar J 2013; 12:327. [PMID: 24041445 PMCID: PMC3848758 DOI: 10.1186/1475-2875-12-327] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2013] [Accepted: 09/11/2013] [Indexed: 11/30/2022] Open
Abstract
Background Malaria is a major public health challenge in sub-Saharan Africa. In Uganda, malaria is the leading cause of morbidity and mortality especially among children under five years of age. This pilot project promoted prevention of malaria at household level using an integrated approach in two rural communities in Wakiso District, Uganda. This involved advocating and implementing several strategies in a holistic manner geared towards reduction in the occurrence of malaria. The specific strategies involved can be classified as: 1) personal protection – use of insecticide-treated bed nets and insecticide sprays; 2) reducing mosquito breeding sites – draining pools of water, larviciding and clearing unnecessary vegetation around homes; and 3) reducing entry of mosquitoes into houses – installing mosquito proofing in windows, ventilators and open eaves, and closing windows and doors early in the evenings. Case description The objectives of the project were to: carry out a baseline survey on malaria prevention; train community health workers and increase awareness among the community on the integrated approach to malaria prevention; and, establish demonstration sites using the integrated approach. A baseline survey among 376 households was conducted which generated information on the knowledge, attitudes and practices of the community in relation to malaria prevention. The project trained 25 community health workers and over 200 community members were sensitized on the integrated approach to malaria prevention. In addition, 40 demonstration households using the integrated approach were established. Discussion and evaluation The use of multiple methods in the prevention of malaria was appreciated by the community particularly the demonstration households using the integrated approach. Initial project evaluation showed that the community had become more knowledgeable about the various malaria prevention methods that were advocated in the integrated approach. In addition, some of the methods that were not being used before project implementation, such as early closing of windows, had been adopted. The presence of mosquitoes in the demonstration households had also reduced. Conclusion The integrated approach to malaria prevention at household level was well perceived by the project community, which could be scaled up to other areas. More rigorous studies such as randomized controlled trials are also recommended to further explore the public health impact of the integrated approach to malaria prevention.
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Woyessa A, Deressa W, Ali A, Lindtjørn B. Malaria risk factors in Butajira area, south-central Ethiopia: a multilevel analysis. Malar J 2013; 12:273. [PMID: 23914971 PMCID: PMC3750841 DOI: 10.1186/1475-2875-12-273] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2013] [Accepted: 07/30/2013] [Indexed: 11/18/2022] Open
Abstract
Background The highlands of Ethiopia, situated between 1,500 and 2,500 m above sea level, experienced severe malaria epidemics. Despite the intensive control attempts, underway since 2005 and followed by an initial decline, the disease remained a major public health concern. The aim of this study was to identify malaria risk factors in highland-fringe south-central Ethiopia. Methods This study was conducted in six rural kebeles of Butajira area located 130 km south of Addis Ababa, which are part of demographic surveillance site in Meskan and Mareko Districts, Ethiopia. Using a multistage sampling technique 750 households was sampled to obtain the 3,398 people, the estimated sample size for this study. Six repeated cross-sectional surveys were conducted from October 2008 to June 2010. Multilevel, mixed-effects logistic regression models fitted to Plasmodium infection status (positive or negative) and six variables. Both fixed- and random-effects differences in malaria infection were estimated using median odds ratio and interval odds ratio 80%. The odds ratios and 95% confidence intervals were used to estimate the strength of association. Results Overall, 19,207 individuals were sampled in six surveys (median and inter-quartile range value three). Six of the five variables had about two-fold to eight-fold increase in prevalence of malaria. Furthermore, among these variables, October-November survey seasons of both during 2008 and 2009 were strongly associated with increased prevalence of malaria infection. Children aged below five years (adjusted OR= 3.62) and children aged five to nine years (adj. OR= 3.39), low altitude (adj. OR= 5.22), mid-level altitude (adj. OR= 3.80), houses with holes (adj. OR= 1.59), survey seasons such as October-November 2008 (adj. OR= 7.84), January-February 2009 (adj. OR= 2.33), June-July 2009 (adj. OR=3.83), October-November 2009 (adj. OR= 7.71), and January-February 2010 (adj. OR= 3.05) were associated with increased malaria infection. The estimates of cluster variances revealed differences in malaria infection. The village-level intercept variance for the individual-level predictor (0.71 [95% CI: 0.28-1.82]; SE=0.34) and final (0.034, [95% CI: 0.002-0.615]; SE=0.05) were lower than that of empty (0.80, [95% CI: 0.32-2.01]; SE=0.21). Conclusion Malaria control efforts in highland fringes must prioritize children below ten years in designing transmission reduction of malaria elimination strategy.
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Affiliation(s)
- Adugna Woyessa
- Ethiopian Health and Nutrition Research Institute, P, O, Box 1242/5654, Addis Ababa, Ethiopia.
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Dræbel T, Kueil BG, Meyrowitsch DW. Prevalence of malaria and use of malaria risk reduction measures among resettled pregnant women in South Sudan. Int Health 2013; 5:211-6. [PMID: 24030272 DOI: 10.1093/inthealth/iht008] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND The study assessed aspects of malaria infection, prevention and treatment in a population of resettled pregnant women in South Sudan. METHODS During April and May 2008, a cross-sectional study was carried out to estimate malaria prevalence and to assess the use of malaria risk reduction measures and their associations with selected background characteristics. Two hundred and twenty women were tested for malaria parasitaemia and questioned about their malaria prevention and treatment practices. RESULTS The results showed a prevalence of Plasmodium falciparum parasitaemia of 9.1%. No statistically significant associations were observed between selected background characteristics and malaria infection status. However, school attendance was significantly associated with insecticide-treated net ownership (OR = 6.52, 95% CI 2.37-17.94; p = 0.001) and access to malaria diagnosis and treatment (OR = 3.20, 95% CI 1.26-8.16; p = 0.015). CONCLUSIONS The results suggest that educational attainment need not be very advanced to affect practices of malaria prevention and treatment. Primary school attendance was a stronger predictor for use of malaria risk reduction measures than any of the other selected background characteristics. Educational attainment, information and communication about malaria prevention and control play a pivotal role in increasing and improving use of malaria risk reduction measures.
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Affiliation(s)
- Tania Dræbel
- Department of International Health, Immunology and Microbiology, University of Copenhagen, Østerfarigmagsgade 5A, 1014 Copenhagen K, Denmark
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Abate A, Degarege A, Erko B. Community knowledge, attitude and practice about malaria in a low endemic setting of Shewa Robit Town, northeastern Ethiopia. BMC Public Health 2013; 13:312. [PMID: 23566168 PMCID: PMC3626609 DOI: 10.1186/1471-2458-13-312] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2012] [Accepted: 04/03/2013] [Indexed: 11/26/2022] Open
Abstract
Background Since malaria is one of the foremost public health problems in Ethiopia, assessment of situation of the disease, and communities’ knowledge and perceptions about malaria is necesary to institute appropriate preventive and control measures. Thus, the aim of this study was to assess malaria prevalence and knowledge, attitude and practice (KAP) about the disease among ShewaRobit Town community, northeastern Ethiopia. Methods A community-based cross-sectional study was conducted in Shewa Robit Town from October to November 2011. A multi-stage random sampling technique was used to select the study participants. A total of 425 individuals were examined for malaria using thin and thick Giemsa stained blood film, and 284 of the participants were interviewed to assess their KAP about malaria. Logistic regression analysis was used to assess predictor factors for malaria prevalence. Results All respondents had ever heard of malaria. Most of the respondents (85.2%) attributed the cause of malaria to mosquito bite. However, some of the respondents (>20%) mentioned lack of personal hygiene, exposure to cold weather, hunger, chewing maize stalk, body contact with malaria patient and flies as the causes of malaria. Sleeping under mosquito nets, draining stagnant water and indoor residual spraying were the most frequently mentioned malaria preventive measures perceived and practiced by the respondents. Among 425 individuals examined for malaria, only 2.8% were positive for Plasmodium parasites. Living in houses made of wall without hole, sprayed with insecticide within the last 12 hours and located at a distance of greater than 500 meters from potential mosquito breeding sites as well as knowing and using of mosquito net were significant predictors of low malaria prevalence among the study participants. Conclusions A high level of knowledge about the cause, transmission and preventive methods of malaria was detected among the community in Shewa Robit Town. However, a considerable proportion had misconception about the cause and transmission of malaria suggesting the necessity of health education to raise the community’s awareness about the disease.
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Affiliation(s)
- Andargie Abate
- Somali Regional State Health Office, P.O. Box 238, Jijga, Ethiopia
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Yewhalaw D, Getachew Y, Tushune K, W Michael K, Kassahun W, Duchateau L, Speybroeck N. The effect of dams and seasons on malaria incidence and anopheles abundance in Ethiopia. BMC Infect Dis 2013; 13:161. [PMID: 23566411 PMCID: PMC3667047 DOI: 10.1186/1471-2334-13-161] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2012] [Accepted: 02/10/2013] [Indexed: 11/24/2022] Open
Abstract
Background Reservoirs created by damming rivers are often believed to increase malaria incidence risk and/or stretch the period of malaria transmission. In this paper, we report the effects of a mega hydropower dam on P. falciparum malaria incidence in Ethiopia. Methods A longitudinal cohort study was conducted over a period of 2 years to determine Plasmodium falciparum malaria incidence among children less than 10 years of age living near a mega hydropower dam in Ethiopia. A total of 2080 children from 16 villages located at different distances from a hydropower dam were followed up from 2008 to 2010 using active detection of cases based on weekly house to house visits. Of this cohort of children, 951 (48.09%) were females and 1059 (51.91%) were males, with a median age of 5 years. Malaria vectors were simultaneously surveyed in all the 16 study villages. Frailty models were used to explore associations between time-to-malaria and potential risk factors, whereas, mixed-effects Poisson regression models were used to assess the effect of different covariates on anopheline abundance. Results Overall, 548 (26.86%) children experienced at least one clinical malaria episode during the follow up period with mean incidence rate of 14.26 cases/1000 child-months at risk (95% CI: 12.16 - 16.36). P. falciparum malaria incidence showed no statistically significant association with distance from the dam reservoir (p = 0.32). However, P. falciparum incidence varied significantly between seasons (p < 0.01). The malaria vector, Anopheles arabiensis, was however more abundant in villages nearer to the dam reservoir. Conclusions P. falciparum malaria incidence dynamics were more influenced by seasonal drivers than by the dam reservoir itself. The findings could have implications in timing optimal malaria control interventions and in developing an early warning system in Ethiopia.
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Mapping urban malaria and diarrhea mortality in Accra, Ghana: evidence of vulnerabilities and implications for urban health policy. J Urban Health 2012; 89:977-91. [PMID: 22684425 PMCID: PMC3531344 DOI: 10.1007/s11524-012-9702-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
Historic increase in urban population numbers in the face of shrinking urban economies and declining social services has meant that a large proportion of the urban population lives in precarious urban conditions, which provide the grounds for high urban health risks in low income countries. This study aims to identify, investigate, and contrast the spatial patterns of vulnerability and risk of two major causes of mortality, viz malaria and diarrhea mortalities, in order to optimize resource allocation for effective urban environmental management and improvement in urban health. A spatial cluster analysis of the observed urban malaria and diarrhea mortalities for the whole city of Accra was conducted. We obtained routinely reported mortality data for the period 1998-2002 from the Ghana Vital Registration System (VRS), computed the fraction of deaths due to malaria and diarrhea at the census cluster level, and analyzed and visualized the data with Geographic Information System (GIS, ArcMap 9.3.1). Regions of identified hotspots, cold spots, and excess mortalities were observed to be associated with some socioeconomic and neighborhood urban environmental conditions, suggesting uneven distribution of risk factors for both urban malaria and diarrhea in areas of rapid urban transformation. Case-control and/or longitudinal studies seeking to understand the individual level factors which mediate socioenvironmental conditions in explaining the observed excess urban mortalities and to establish the full range of risk factors might benefit from initial vulnerability mapping and excess risk analysis using geostatistical approaches. This is key to evidence-based urban health policy reforms in rapidly urbanizing areas in low income economies.
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Determinants of ownership and utilization of insecticide-treated bed nets for malaria control in eastern ethiopia. J Trop Med 2012; 2012:235015. [PMID: 23209476 PMCID: PMC3503393 DOI: 10.1155/2012/235015] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2012] [Revised: 09/21/2012] [Accepted: 10/14/2012] [Indexed: 11/17/2022] Open
Abstract
Background. Malaria remains a major cause of mortality and morbidity in the world, and particularly in sub-Saharan Africa. Objectives. The aim of this study was to determine ownership and utilization of ITNs among households with children under five in the previous night. Methods. A community based cross-sectional study was conducted in Gursum district in Eastern Ethiopia. A total of 335 households were surveyed using a pretested structured questionnaire administered though house-to-house interviews. Results. Household ownership for at least one mosquito net and use of nets were 62.4% (95% CI 57.2–67.6%) and 21.5% (95% CI 17.1–25.9%), respectively. Households who received or were told about ITN in the last 6 months were three times more likely to have used it than those who were not (OR 3.25; 95% CI 1.5–7.10). Households whose heads were engaged as a farmer (adjusted OR 0.137; 95% CI: 0.04–0.50) and housewife (OR 0.26; 95% CI: 0.08–0.82) were less likely to use ITN than those of other occupations. Conclusion. The findings indicate low ITN ownership and utilization among the households. Intensive health education and community mobilization effort should be employed to increase the possession and proper utilization of insecticide treated bed nets.
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Malaria in selected non-Amazonian countries of Latin America. Acta Trop 2012; 121:303-14. [PMID: 21741349 DOI: 10.1016/j.actatropica.2011.06.008] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2011] [Revised: 06/07/2011] [Accepted: 06/23/2011] [Indexed: 01/29/2023]
Abstract
Approximately 170 million inhabitants of the American continent live at risk of malaria transmission. Although the continent's contribution to the global malaria burden is small, at least 1-1.2 million malaria cases are reported annually. Sixty percent of the malaria cases occur in Brazil and the other 40% are distributed in 20 other countries of Central and South America. Plasmodium vivax is the predominant species (74.2%) followed by P. falciparum (25.7%) and P. malariae (0.1%), and no less than 10 Anopheles species have been identified as primary or secondary malaria vectors. Rapid deforestation and agricultural practices are directly related to increases in Anopheles species diversity and abundance, as well as in the number of malaria cases. Additionally, climate changes profoundly affect malaria transmission and are responsible for malaria epidemics in some regions of South America. Parasite drug resistance is increasing, but due to bio-geographic barriers there is extraordinary genetic differentiation of parasites with limited dispersion. Although the clinical spectrum ranges from uncomplicated to severe malaria cases, due to the generally low to middle transmission intensity, features such as severe anemia, cerebral malaria and other complications appear to be less frequent than in other endemic regions and asymptomatic infections are a common feature. Although the National Malaria Control Programs (NMCP) of different countries differ in their control activities these are all directed to reduce morbidity and mortality by using strategies like health promotion, vector control and impregnate bed nets among others. Recently, international initiatives such as the Malaria Control Program in Andean-country Border Regions (PAMAFRO) (implemented by the Andean Organism for Health (ORAS) and sponsored by The Global Fund to Fight AIDS, Tuberculosis and Malaria (GFATM)) and The Amazon Network for the Surveillance of Antimalarial Drug Resistance (RAVREDA) (sponsored by the Pan American Health Organization/World Health Organization (PAHO/WHO) and several other partners), have made great investments for malaria control in the region. We describe here the current status of malaria in a non-Amazonian region comprising several countries of South and Central America participating in the Centro Latino Americano de Investigación en Malaria (CLAIM), an International Center of Excellence for Malaria Research (ICEMR) sponsored by the National Institutes of Health (NIH) National Institute of Allergy and Infectious Diseases (NIAID).
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Naidoo S, London L, Burdorf A, Naidoo RN, Kromhout H. Occupational activities associated with a reported history of malaria among women working in small-scale agriculture in South Africa. Am J Trop Med Hyg 2011; 85:805-10. [PMID: 22049030 DOI: 10.4269/ajtmh.2011.11-0092] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Malaria-endemic agricultural communities are at risk for this disease because of crop and agricultural activities. A cross-sectional survey among women in small-scale agriculture on irrigated and dryland areas in Makhatini Flats, KwaZulu-Natal South Africa explored associations with self-reported history of malaria, including demographics, crop production, and specific agricultural activities. Ninety-eight (15.2%) of 644 women reported malaria while working in agriculture. More women working in drylands than women working in irrigation scheme reported disease (18.4% versus 10.9%; P < 0.05). Working self or family-owned farms (prevalence ratio [PR] = 2.6, 95% confidence interval [CI] = 1.3-5.2), spraying pesticides (PR = 2.3; 95% CI = 1.4-3.8), cultivating sugar cane (PR = 1.6, 95% CI = 1.1-2.3), and cultivating cotton and mangoes (PR = 1.7, 95% CI = 1.1-2.6) were positively associated with a history of malaria while working in agriculture. This study suggests that certain agricultural activities and types of crop production may increase the risk for malaria among women working in small-scale agriculture.
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Affiliation(s)
- Saloshni Naidoo
- Department of Occupational and Environmental Health, Nelson R. Mandela School of Medicine, University of KwaZulu-Natal, Congella, Durban, South Africa
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