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Yutura G, Massebo F, Eligo N, Kochora A, Wegayehu T. Prevalence of malaria and associated risk factors among household members in South Ethiopia: a multi-site cross-sectional study. Malar J 2024; 23:143. [PMID: 38735957 PMCID: PMC11088779 DOI: 10.1186/s12936-024-04965-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2023] [Accepted: 04/25/2024] [Indexed: 05/14/2024] Open
Abstract
BACKGROUND Despite continuous prevention and control strategies in place, malaria remains a major public health problem in sub-Saharan Africa including Ethiopia. Moreover, prevalence of malaria differs in different geographical settings and epidemiological data were inadequate to assure disease status in the study area. This study was aimed to determine the prevalence of malaria and associated risk factors in selected rural kebeles in South Ethiopia. METHODS A community-based cross-sectional study was conducted between February to June 2019 in eight malaria-endemic kebeles situated in four zones in South Ethiopia. Mult-stage sampling techniques were employed to select the study zones, districts, kebeles and households. Blood sample were collected from 1674 participants in 345 households by finger prick and smears were examined by microscopy. Sociodemographic data as well as risk factors for Plasmodium infection were collected using questionnaires. Bivariate and multivariate logistic regressions were used to analyse the data. RESULTS The overall prevalence of malaria in the study localities was 4.5% (76/1674). The prevalence was varied among the study localities with high prevalence in Bashilo (14.6%; 33/226) followed by Mehal Korga (12.1%; 26/214). Plasmodium falciparum was the dominant parasite accounted for 65.8% (50/76), while Plasmodium vivax accounted 18.4% (14/76). Co-infection of P. falciparum and P. vivax was 15.8% (12/76). Among the three age groups prevalence was 7.8% (27/346) in age less than 5 years and 7.5% (40/531) in 5-14 years. The age groups > 14years were less likely infected with Plasmodium parasite (AOR = 0.14, 95% CI 0.02-0.82) than under five children. Non-febrile individuals 1638 (97.8%) were more likely to had Plasmodium infection (AOR = 28.4, 95% CI 011.4-70.6) than febrile 36 (2.2%). Individuals living proximity to mosquito breeding sites have higher Plasmodium infection (AOR = 6.17, 95% CI 2.66-14.3) than those at distant of breeding sites. CONCLUSIONS Malaria remains a public health problem in the study localities. Thus, malaria prevention and control strategies targeting children, non-febrile cases and individuals living proximity to breeding sites are crucial to reduce malaria related morbidity and mortality.
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Affiliation(s)
- Girma Yutura
- Malaria and Neglected Tropical Diseases, Gorche Health District, Hawassa, Sidama Regional State, Ethiopia
| | - Fekadu Massebo
- Department of Biology, College of Natural and Competitional Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Nigatu Eligo
- Department of Biology, College of Natural and Competitional Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Abena Kochora
- Malaria and Neglected Tropical Diseases, Armauer Hansen Research Institute, Addis Ababa, Ethiopia
| | - Teklu Wegayehu
- Department of Biology, College of Natural and Competitional Sciences, Arba Minch University, Arba Minch, Ethiopia.
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Bayou FD, Kebede N, Tsega Y, Nigussie S, Legassu TD, Muche A, Muluneh AA, Ayele FY. Under utilization of long-lasting insecticidal nets (LLINs) is challenging malaria elimination program in Ethiopia: a systematic review and meta-analysis. BMC Public Health 2024; 24:815. [PMID: 38491483 PMCID: PMC10941431 DOI: 10.1186/s12889-024-18344-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Accepted: 03/12/2024] [Indexed: 03/18/2024] Open
Abstract
BACKGROUND Malaria is one of the most common causes of morbidity and mortality in developing countries including Ethiopia. Mass distribution of insecticide-treated nets and indoor residual spray for high malaria risk groups are the major prevention measures in different countries. Achievement of the malaria elimination plan is highly determined by the level of effective utilization of intervention measures. However, there is scarce information showing the national level of insecticide-treated nets utilization. OBJECTIVE To estimate the pooled prevalence of insecticide-treated nets utilization in Ethiopia, 2023. METHOD A Systematic Review and Meta-analysis employed to assess the utilization of long-lasting insecticidal nets in Ethiopia. Published articles were searched from Google Scholar, PubMed, Web Sciences, CINAHIL, EMBASE, and Scopus. The collected articles were screened for data extraction and further analysis using preferred reporting items for systematic review and meta-analysis (PRISMA) flow chart. The quality of each study was assessed using the Jonna Briggs Institute (JBI) checklist. The data were extracted using Microsoft Excel and exported to STATA version 17.0 for analysis. The overall pooled prevalence of long-lasting insecticidal nets utilization was determined using a random effects model. RESULT Out of 1657 articles reviewed, only 21 of them were eligible for final analysis. All of the included studies were used to estimate the pooled prevalence of long-lasting insecticidal net utilization. The point prevalence of LLIN utilization ranged from 14.23 to 91.9%. The Meta-analysis estimated that the overall pooled prevalence of insecticidal nets utilization among all study participants in Ethiopia was 56.26% (95%CI: 44.04-68.48%). Subgroup analysis revealed that insecticidal nets utilization was relatively highest in the Amhara region [63.0, 95%CI (37.0-89.0%)] and during 2020-2023 [61, 95% CI (53.0-69.0%)]. CONCLUSION Long-lasting insecticidal nets utilization in Ethiopia is lower than the national target plan. Hence, it needs extra follow-up and intervention to enhance its utilization.
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Affiliation(s)
- Fekade Demeke Bayou
- Department of Epidemiology and Biostatistics, School of Public Health, College of Medicine and Health Sciences, Wollo University, Dessie, Ethiopia.
| | - Natnael Kebede
- Department of Health Promotion, School of Public Health, College of Medicine and Health Sciences, Wollo University, Dessie City, Ethiopia
| | - Yawkal Tsega
- Department of Health System and Project Management, School of Public Health, College of Medicine and Health Sciences, Wollo University, Dessie City, Ethiopia
| | - Shambel Nigussie
- Department of Clinical Pharmacy, School of Pharmacy, College of Health and Medical Science, Haramaya University, Harar, Ethiopia
| | | | - Amare Muche
- Department of Epidemiology and Biostatistics, School of Public Health, College of Medicine and Health Sciences, Wollo University, Dessie, Ethiopia
| | - Ayana Alebachew Muluneh
- Department of Health Informatics, College of Medicine and Health Sciences, Wollo University, Dessie, Ethiopia
| | - Fanos Yeshanew Ayele
- Department of Public Health Nutrition, College of Medicine and Health Sciences, Wollo University, Dessie City, Ethiopia
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Loha E. Association between Livestock Ownership and Malaria Incidence in South-Central Ethiopia: A Cohort Study. Am J Trop Med Hyg 2023; 108:1145-1150. [PMID: 37094783 PMCID: PMC10540100 DOI: 10.4269/ajtmh.22-0719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 03/02/2023] [Indexed: 04/26/2023] Open
Abstract
Zooprophylaxis is one of the possible environmental vector control strategies for malaria prevention. However, its effect on reducing malaria transmission has been questionable, requiring a detailed understanding of contextual factors. This study aims to evaluate the effect of keeping livestock on malaria incidence in south-central Ethiopia. A cohort of 34,548 people in a total of 6,071 households was followed for 121 weeks from October 2014 to January 2017. Baseline data were collected, including livestock ownership. Weekly home visits were done to actively search for malaria cases, and passive case detection was also carried out. Malaria was diagnosed with rapid diagnostic tests. Log binomial and parametric regression survival-time models were used to estimate effect measures. A total of 27,471 residents had complete follow-ups, and the majority (87.5%) lived in households owning livestock, including cattle, sheep, goats, and chickens. The overall incidence risk of malaria was 3.7%, and there was a 24% reduction in the risk of malaria among livestock owners. The total cohort contributed to 71,861.62 person-years of observation. The incidence rate of malaria was 14.7 cases per 1,000 person-years. There was a 17% reduction in the rate of malaria among livestock owners. Meanwhile, the protective effect of livestock ownership increased as the number of livestock or the livestock-to-human ratio increased. In conclusion, livestock owners had less malaria. In a setup where domestication of livestock is a common practice and the predominant malaria vector tends to feed more on livestock than humans, zooprophylaxis remains a promising strategy for malaria prevention.
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Affiliation(s)
- Eskindir Loha
- Centre for International Health, University of Bergen, Bergen, Norway
- Chr. Michelsen Institute, Bergen, Norway
- School of Public Health, Hawassa University, Hawassa, Ethiopia
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Aweis A, Salad AA, Araye FA, Ahmed AM, Wehlie OA, Osman AA, Akuku IG. Long-lasting insecticidal nets (LLINs) use among household members for protection against mosquito bite in Mogadishu districts. PLOS GLOBAL PUBLIC HEALTH 2023; 3:e0000724. [PMID: 36962968 PMCID: PMC10019640 DOI: 10.1371/journal.pgph.0000724] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 02/14/2023] [Indexed: 03/18/2023]
Abstract
Understanding long-lasting insecticidal nets (LLINs) utilization is important in monitoring and quantifying the impact of past and current prevention and control efforts of malaria. A cross-sectional study was carried out on a sample of 409 households in Mogadishu, to estimate the LLIN use and assess barriers to its utilization. A standardized questionnaire was used to collect data on demographics, malaria-related knowledge, and the use of preventive measures. LLINs use was assessed using multivariable generalized estimating equations with adjustment for clustering of study participants within the same household. Out of 409 households only 155 (37.9%) owned LLINs. Out of 237 owned LLINs, 199 (84.0%) were used. Median household size being 6.0 (3.0), intra-household net accessibility was low, with one net (42.6%) frequent. Most nets were from mass distribution (55.7%) and obtained '12 months ago'. Un-partnered respondents (unadjusted odds ratio [OR] 0.34, 95% CI 0.14, 0.82; p = 0.017) compared with partnered (married) respondents, large-sized household (adjusted OR 0.83, 96% CI 0.74-0.94; p = 0.002). There was marginal evidence of a greater odds of LLIN utilization among respondents knowledgeable of the correct cause of malaria, that is, mosquito bites (AOR 3.19, 95% CI 0.77, 13.2; p = 0.11) but was not statistically significant. Among households owning nets, most of the LLINs were hung the night prior to the survey (7.9% versus 98%) and was associated with greater marginal odds of utilization (p<0.001). Ownership of LLINs is insufficient in Mogadishu districts affecting household-level access and utilization. If this is not checked, this could weaken the progress made on malaria control efforts. LLIN utilization was modest and largely driven by recently acquired nets showing a desire to utilize them despite low coverage. These imply that mass and facility-based distribution, and awareness campaigns will remain relevant, but efforts for willingness-to-pay for LLINs should be strengthened to sustain coverage and replacements of worn-out nets.
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Affiliation(s)
- Ahmed Aweis
- Benadir University, Mogadishu, Somalia
- * E-mail:
| | | | | | | | | | | | - Isaiah Gumbe Akuku
- Institute of Tropical and Infectious Diseases, University of Nairobi, Nairobi, Kenya
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Ngonghala CN. Assessing the impact of insecticide-treated nets in the face of insecticide resistance on malaria control. J Theor Biol 2022; 555:111281. [PMID: 36154815 DOI: 10.1016/j.jtbi.2022.111281] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 09/01/2022] [Accepted: 09/17/2022] [Indexed: 01/14/2023]
Abstract
The mosquito-borne disease, malaria, continues to impose a devastating health and economic burden worldwide. In malaria-endemic areas, insecticide-treated nets (ITNs) have been useful in curtailing the burden of the disease. However, mosquito resistance to insecticides, decay in ITN efficacy, net attrition, etc., undermine the effectiveness of ITNs in combatting malaria. In this study, mathematical models that account for asymptomatic infectious humans (through a partially immune class or a separate asymptomatic infectious class), insecticide resistance, and decay in ITN efficacy are proposed and analyzed. Analytical and numerical results of the models when ITN efficacy is constant show that there are parameter regimes for which a backward bifurcation occurs. Local and global sensitivity analyses are performed to identify parameters (some of which are potential targets for disease control) with the most significant influence on the control reproduction (Rc) and disease prevalence. These influential parameters include the maximum biting rate of resistant mosquitoes, ITN coverage, initial ITN efficacy against sensitive mosquitoes, the probability that an infectious mosquito (human) infects a susceptible human (mosquito), and the rate at which adult mosquitoes develop (lose) resistance to insecticides. Simulations of the models show that accounting for asymptomatic infectious humans through a separate class, or not accounting for the decay in ITN efficacy leads to an underestimation of disease burden. In particular, if the initial efficacy of ITNs against sensitive and resistance mosquitoes is 96%, the minimum ITN coverage required to reduce Rc below one (and hence, contain malaria) is approximately 11% (27%) lower when ITN efficacy is averaged (constant) for a model with a separate asymptomatic class. For the model with a partially immune class and decaying ITN efficacy, reducing Rc below one is impossible even if the entire populace uses ITNs. The study shows that replacing ITNs before their prescribed lifespans, or designing ITNs with longer lifespans is important for malaria control. Furthermore, the study shows that piperonyl butoxide (PBO) ITNs (which inhibit or reverse insecticide resistance) outperform regular ITNs in malaria control. Hence, prospects for effectively controlling malaria are enhanced by widespread use of high quality ITNs (e.g. PBO ITNs), especially if the useful lifespans of the ITNs are long enough and the ITNs are replaced before the end of their useful lifespans.
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Affiliation(s)
- Calistus N Ngonghala
- Department of Mathematics, University of Florida, 1400 Stadium Rd, Gainesville, FL 32611, United States of America; Emerging Pathogens Institute, University of Florida, 2055 Mowry Rd, Gainesville, FL 32610, United States of America; Center for African Studies, University of Florida, 427 Grinter Hall 1523 Union Rd, Gainesville, FL 32611, United States of America.
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Elmardi KA, Adam I, Malik EM, Kafy HT, Abdin MS, Kleinschmidt I, Kremers S, Gubbels JS. Impact of malaria control interventions on malaria infection and anaemia in low malaria transmission settings: a cross-sectional population-based study in Sudan. BMC Infect Dis 2022; 22:927. [PMID: 36496398 PMCID: PMC9737986 DOI: 10.1186/s12879-022-07926-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Accepted: 12/06/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND The past two decades were associated with innovation and strengthening of malaria control interventions, which have been increasingly adopted at large scale. Impact evaluations of these interventions were mostly performed in moderate or high malaria transmission areas. This study aimed to evaluate the use and performance of malaria interventions in low transmission areas on malaria infections and anaemia. METHODS Data from the 2016 Sudan malaria indicator survey was used. Multi-level logistic regression analysis was used to assess the strength of association between real-life community-level utilization of malaria interventions [diagnosis, artemisinin-based combination therapies (ACTs) and long-lasting insecticidal nets (LLINs)] and the study outcomes: malaria infections and anaemia (both overall and moderate-to-severe anaemia). RESULTS The study analysis involved 26,469 individuals over 242 clusters. Malaria infection rate was 7.6%, overall anaemia prevalence was 47.5% and moderate-to-severe anaemia prevalence was 4.5%. The average community-level utilization was 31.5% for malaria diagnosis, 29.9% for ACTs and 35.7% for LLINs. The odds of malaria infection was significantly reduced by 14% for each 10% increase in the utilization of malaria diagnosis (adjusted odds ratio (aOR) per 10% utilization 0.86, 95% CI 0.78-0.95, p = 0.004). However, the odds of infection was positively associated with the utilization of LLINs at community-level (aOR per 10% utilization 1.20, 95% CI 1.11-1.29, p < 0.001). No association between malaria infection and utilization of ACTs was identified (aOR per 10% utilization 0.97, 95% CI 0.91-1.04, p = 0.413). None of the interventions was associated with overall anaemia nor moderate-to-severe anaemia. CONCLUSION There was strong evidence that utilization of malaria diagnosis at the community level was highly protective against malaria infection. No protective effect was seen for community utilization of ACTs or LLINs. No association was established between any of the interventions and overall anaemia or moderate-to-severe anaemia. This lack of effectiveness could be due to the low utilization of interventions or the low level of malaria transmission in the study area. Identification and response to barriers of access and low utilization of malaria interventions are crucial. It is crucial to ensure that every suspected malaria case is tested in a timely way, notably in low transmission settings.
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Affiliation(s)
- Khalid Abdelmutalab Elmardi
- grid.414827.cHealth Information, Monitoring and Evaluation and Evidence Department, Federal Ministry of Health, Khartoum, Sudan ,grid.5012.60000 0001 0481 6099Department of Health Promotion, Faculty of Health, Medicine and Life Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht, The Netherlands
| | - Ishag Adam
- grid.412602.30000 0000 9421 8094Department of Obstetrics and Gynecology, Unaizah College of Medicine and Medical Sciences, Qassim University, Unaizah, Saudi Arabia
| | - Elfatih Mohamed Malik
- grid.9763.b0000 0001 0674 6207Faculty of Medicine, University of Khartoum, Khartoum, Sudan
| | - Hmooda Toto Kafy
- grid.414827.cDirectorate General of Primary Health Care, Federal Ministry of Health, Khartoum, Sudan
| | - Mogahid Sheikheldien Abdin
- grid.414827.cHealth Information, Monitoring and Evaluation and Evidence Department, Federal Ministry of Health, Khartoum, Sudan
| | - Immo Kleinschmidt
- grid.8991.90000 0004 0425 469XMRC International Statistics and Epidemiology Group, Department of Infectious Disease Epidemiology, London School of Hygiene and Tropical Medicine, London, UK ,grid.11951.3d0000 0004 1937 1135Faculty of Health Sciences, School of Pathology, Wits Research Institute for Malaria, University of the Witwatersrand, Johannesburg, South Africa ,Southern African Development Community Malaria Elimination Eight Secretariat, Windhoek, Namibia
| | - Stef Kremers
- grid.5012.60000 0001 0481 6099Department of Health Promotion, Faculty of Health, Medicine and Life Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht, The Netherlands
| | - Jessica Sophia Gubbels
- grid.5012.60000 0001 0481 6099Department of Health Promotion, Faculty of Health, Medicine and Life Sciences, NUTRIM School of Nutrition and Translational Research in Metabolism, Maastricht, The Netherlands
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Abong’o B, Gimnig JE, Omoke D, Ochomo E, Walker ED. Screening eaves of houses reduces indoor mosquito density in rural, western Kenya. Malar J 2022; 21:377. [PMID: 36494664 PMCID: PMC9733111 DOI: 10.1186/s12936-022-04397-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 11/22/2022] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Despite the scale-up of insecticide-treated nets and indoor residual spraying, the bulk of malaria transmission in western Kenya still occurs indoors, late at night. House improvement is a potential long-term solution to further reduce malaria transmission in the region. METHODS The impact of eave screening on mosquito densities was evaluated in two rural villages in western Kenya. One-hundred-and-twenty pairs of structurally similar, neighbouring houses were used in the study. In each pair, one house was randomly selected to receive eave screening at the beginning of the study while the other remained unscreened until the end of the sampling period. Mosquito sampling was performed monthly by motorized aspiration method for 4 months. The collected mosquitoes were analysed for species identification. RESULTS Compared to unscreened houses, significantly fewer female Anopheles funestus (RR = 0.40, 95% CI 0.29-0.55), Anopheles gambiae Complex (RR = 0.46, 95% CI 0.34-0.62) and Culex species (RR = 0.53, 95% CI 0.45-0.61) were collected in screened houses. No significant differences in the densities of the mosquitoes were detected in outdoor collections. Significantly fewer Anopheles funestus were collected indoors from houses with painted walls (RR = 0.05, 95% CI 0.01-0.38) while cooking in the house was associated with significantly lower numbers of Anopheles gambiae Complex indoors (RR = 0.60, 95% CI 0.45-0.79). Nearly all house owners (99.6%) wanted their houses permanently screened, including 97.7% that indicated a willingness to use their own resources. However, 99.2% required training on house screening. The cost of screening a single house was estimated at KES6,162.38 (US$61.62). CONCLUSION Simple house modification by eave screening has the potential to reduce the indoor occurrence of both Anopheles and Culex mosquito species. Community acceptance was very high although education and mobilization may be needed for community uptake of house modification for vector control. Intersectoral collaboration and favourable government policies on housing are important links towards the adoption of house improvements for malaria control.
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Affiliation(s)
- Bernard Abong’o
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - John E. Gimnig
- grid.416738.f0000 0001 2163 0069Centers for Disease Control and Prevention, Division of Parasitic Diseases, Atlanta, GA 30341 USA
| | - Diana Omoke
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Eric Ochomo
- grid.33058.3d0000 0001 0155 5938Centre for Global Health Research, Kenya Medical Research Institute, P.O. Box 1578-40100, Kisumu, Kenya
| | - Edward D. Walker
- grid.17088.360000 0001 2150 1785Michigan State University, 6169 Biomedical Physical Sciences Building, East Lansing, MI 48824 USA
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Ngonghala CN, Bhattacharyya S. An evolutionary game model of individual choices and bed net use: elucidating key aspect in malaria elimination strategies. ROYAL SOCIETY OPEN SCIENCE 2022; 9:220685. [PMID: 36405633 PMCID: PMC9667140 DOI: 10.1098/rsos.220685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2022] [Accepted: 10/25/2022] [Indexed: 06/16/2023]
Abstract
Insecticide-treated net (ITN) is the most applicable and cost-effective malaria intervention measure in sub-Saharan Africa and elsewhere. Although ITNs have been widely distributed to malaria-endemic regions in the past, their success has been threatened by misuses (in fishing, agriculture etc.) and decay in ITN efficacy. Decision-making in using the ITNs depends on multiple coevolving factors: malaria prevalence, mosquito density, ITN availability and its efficacy, and other socio-economic determinants. While ITN misuse increases as the efficacy of ITNs declines, high efficacy also impedes proper use due to free-riding. This irrational usage leads to increased malaria prevalence, thereby worsening malaria control efforts. It also remains unclear if the optimum ITN use for malaria elimination can be achieved under such an adaptive social learning process. Here, we incorporate evolutionary game theory into a disease transmission model to demonstrate these behavioural interactions and their impact on malaria prevalence. We show that social optimum usage is a function of transmission potential, ITN efficacy and mosquito demography. Under specific parameter regimes, our model exhibits patterns of ITN usage similar to observed data from parts of Africa. Our study suggests that the provision of financial incentives as prompt feedback to improper ITN use can reduce misuse and contribute positively towards malaria elimination efforts in Africa and elsewhere.
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Affiliation(s)
- Calistus N. Ngonghala
- Department of Mathematics and Emerging Pathogens Institute, University of Florida, Gainesville, FL 32611, USA
| | - Samit Bhattacharyya
- Disease Modelling Lab, Department of Mathematics, School of Natural Sciences, Shiv Nadar University, Gautam Buddha Nagar, India
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9
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Asmare G. Willingness to accept malaria vaccine among caregivers of under-5 children in Southwest Ethiopia: a community based cross-sectional study. Malar J 2022; 21:146. [PMID: 35549710 PMCID: PMC9097094 DOI: 10.1186/s12936-022-04164-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 04/18/2022] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Malaria is widespread in Ethiopia and has been a major cause of illness and death in that country. Therefore, Ethiopia has been exerting enormous efforts towards eliminating malaria by 2030. In the context of comprehensive malaria control, the malaria vaccine is used for the prevention of Plasmodium falciparum malaria in children living in regions with moderate- to-high malaria transmission. METHODS A community-based cross-sectional study was conducted among caregivers of children under the age of five throughout the months of September 2021. A structured interviewer-administered questionnaire was designed for data collection, and binary logistic regression analysis was used. The final result of the association was determined based on an adjusted odds ratio (AOR) at a 95% confidence interval (CI) level, and p < 0.05 indicated statistical significance. RESULTS A total of 406 caregivers of children under the age of 5 were interviewed. Overall, 131 (32.3%) respondents were willing to vaccinate their children. Marital status (AOR = 1.243; 95% CI 1.021-3.897), knowledge (AOR = 3.120; 95% CI 1.689-5.027), and previous experience with childhood vaccination (AOR = 2.673; 95% CI 1.759-4.101) were found to be significantly associated with willingness to accept a malaria vaccine for their children, at p < 0.05. CONCLUSIONS AND RECOMMENDATIONS The willingness to accept a malaria vaccine for children among caregivers of children under the age of five was low in the study area. Thus, health education and communication are crucial for alleviating poor knowledge about malaria vaccines.
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Affiliation(s)
- Getachew Asmare
- Department of Reproductive Health and Nutrition, School of Public Health, College of Health Science and Medicine, Wolaita Sodo University, Wolaita Sodo, Ethiopia.
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Hiruy HN, Zewde A, Irish SR, Abdelmenan S, Woyessa A, Wuletaw Y, Solomon H, Haile M, Sisay A, Chibsa S, Worku A, Yukich J, Berhane Y, Keating J. The effect of long-lasting insecticidal nets (LLINs) physical integrity on utilization. Malar J 2021; 20:468. [PMID: 34922543 PMCID: PMC8684122 DOI: 10.1186/s12936-021-03976-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 11/07/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND In Ethiopia, despite improvements in coverage and access, utilization of long-lasting insecticidal nets (LLINs) remains a challenge. Different household-level factors have been identified as associated with LLIN use. However, the contribution of LLIN physical integrity to their utilization is not well investigated and documented. This study aimed to assess the association between the physical integrity of LLINs and their use. METHODS This study employed a nested case-control design using secondary data from the Ethiopian LLIN durability monitoring study conducted from May 2015 to June 2018. LLINs not used the night before the survey were identified as cases, while those used the previous night were categorized as controls. The physical integrity of LLINs was classified as no holes, good, acceptable, and torn using the proportionate hole index (pHI). A Generalized Estimating Equation (GEE) model was used to assess and quantify the association between LLIN physical integrity and use. The model specifications included binomial probabilistic distribution, logit link, exchangeable correlation matrix structure, and robust standard errors. The factors included in the model were selected first by fitting binary regression, and then by including all factors that showed statistical significance at P-value less than 0.25 and conceptually relevant variables into the multivariate regression model. RESULTS A total of 5277 observations fulfilled the inclusion criteria. Out of these 1767 observations were cases while the remaining 3510 were controls. LLINs that were in torn physical condition had higher odds (AOR [95% CI] = 1.76 [1.41, 2.19]) of not being used compared to LLINs with no holes. Other factors that showed significant association included the age of the LLIN, sleeping place type, washing status of LLINs, perceptions towards net care and repair, LLIN to people ratio, economic status, and study site. CONCLUSION AND RECOMMENDATION LLINs that have some level of physical damage have a relatively higher likelihood of not being used. Community members need to be educated about proper care and prevention of LLIN damage to delay the development of holes as long as possible and use available LLINs regularly.
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Affiliation(s)
| | - Ayele Zewde
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | - Seth R Irish
- Center for Disease Control (CDC), Atlanta, USA.,US President's Malaria Initiative (PMI), Addis Ababa, Ethiopia
| | | | - Adugna Woyessa
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Yonas Wuletaw
- Ethiopian Public Health Institute, Addis Ababa, Ethiopia
| | - Hiwot Solomon
- Ethiopia Federal Ministry of Health, Addis Ababa, Ethiopia
| | | | | | - Sheleme Chibsa
- US President's Malaria Initiative (PMI), Addis Ababa, Ethiopia
| | - Alemayehu Worku
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | - Josh Yukich
- Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
| | - Yemane Berhane
- Addis Continental Institute of Public Health, Addis Ababa, Ethiopia
| | - Joseph Keating
- Tulane University School of Public Health and Tropical Medicine, New Orleans, LA, USA
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11
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Pooseesod K, Parker DM, Meemon N, Lawpoolsri S, Singhasivanon P, Sattabongkot J, Cui L, Phuanukoonnon S. Ownership and utilization of bed nets and reasons for use or non-use of bed nets among community members at risk of malaria along the Thai-Myanmar border. Malar J 2021; 20:305. [PMID: 34229653 PMCID: PMC8259116 DOI: 10.1186/s12936-021-03837-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 06/27/2021] [Indexed: 11/22/2022] Open
Abstract
Background With the goal for malaria elimination in Thailand set for 2024, increased coverage and utilization of bed net, especially insecticide-treated net (ITN) or long-lasting insecticidal net (LLIN) is a key strategy. This study aims to provide the necessary information about bed net ownership and utilization among the population at risk of malaria living along the Thai-Myanmar border in Tak province. Methods A cross-sectional study was conducted using a mixed-method approach in 331 households from 5 hamlets in the villages of the Thai-Myanmar border. The research tools included a questionnaire, bed net inspection, and semi-structured interviews. Logistic regression was used to explore the sociodemographic factors associated with bed net utilization. The qualitative analysis employed a thematic analysis approach. Results This survey found that 98.5% of households had at least one bed net per household, and 74.3% had at least one ITN/LLIN. However, only 30.8% of households reached the standard policy set by the Minister of Public Health of one ITN/LLINs per two persons. Most residents used bed net (92.1% used in the previous night and 80.9% used every day). For those using bed nets, however, 61.9% used ITNs or LLINs the night before and 53.1% used them every day. Nonetheless, the usage rates of bed nets (any type) in the previous night among children and pregnant women were high, reaching 95.3% and 90.0%, respectively. Seven explanatory variables showed statistically significant associations with bed net use every day, including: “not staying overnight in the forest or the field”, “sleeping pattern based on gender”, “sufficient numbers of bed nets to cover all sleeping spaces”, “preference for free bed nets”, “age”, “gender”, and “SES score” showed statistically significant association with bed net use every day. The major reasons for the regular use of bed nets in both household and the forest were to prevent mosquito biting. The reasons for not using bednets in the household were discomfort feelings from heat, perception of unnecessity due to low mosquito density, whereas the reason for not using bed nets in the forest was inconvenience. Conclusion Despite that overall coverage and usage of bed nets was high, only one third reached the standard level specified by the policy. Overnight in the forest, the dissatisfaction with the quality of free bed nets, insufficient number of bed nets, sleeping alone, male gender, age more than 10 years, low socioeconomic status, discomfort from heat, perception of no benefits of bed nets due to low mosquito density, and inconvenience were factors influencing bed net use. Maintaining high coverage and utility rate of bed nets should be a priority for the malaria high-risk population. Supplementary Information The online version contains supplementary material available at 10.1186/s12936-021-03837-5.
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Affiliation(s)
- Kasama Pooseesod
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand.,Faculty of Public Health, Thammasat University, Bangkok, Thailand
| | - Daniel M Parker
- Department of Population Health & Disease Prevention, Program in Public Health Susan and Henry Samueli College of Health Sciences, University of California, Irvine, USA
| | - Natthani Meemon
- Department of Society and Health, Faculty of Social Sciences and Humanities, Mahidol University, Nakhon Pathom, Thailand
| | - Saranath Lawpoolsri
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand
| | - Pratap Singhasivanon
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand.,Faculty of Tropical Medicine, SEAMEO TROPMED Regional Centre for Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand
| | - Jetsumon Sattabongkot
- Mahidol Vivax Research Unit, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand
| | - Liwang Cui
- Department of Internal Medicine, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Suparat Phuanukoonnon
- Department of Tropical Hygiene, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand. .,Department of Social and Environmental Medicine, Faculty of Tropical Medicine, Mahidol University, Nakhon Pathom, Thailand.
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12
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Gari T, Solomon T, Lindtjørn B. Older children are at increased risk of Plasmodium vivax in south-central Ethiopia: a cohort study. Malar J 2021; 20:251. [PMID: 34092235 PMCID: PMC8183059 DOI: 10.1186/s12936-021-03790-3] [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: 03/11/2021] [Accepted: 05/29/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Better understanding of the distribution of Plasmodium vivax and its risk factors could be used to prevent and control malaria infection. Therefore, the aim of this study was to characterize the distribution and risk factors of P. vivax, and to compare them with Plasmodium falciparum occurrence in south-central Ethiopia. METHODS A cohort of 34,548 individuals were followed for 121 weeks between 2014 and 2016 as part of larger cluster randomized controlled trial to evaluate the effect of long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) on malaria prevention in Ethiopia. Weekly home visit (active search) and patient self- report to health post (passive search) between the weekly home visits were used to register malaria cases. A blood sample was collected by finger prick and malaria was diagnosed using rapid diagnostic test (RDT). Generalized estimating equation (GEE) Poisson model that accounts for repeated measure of malaria episodes was applied to assess the risk factors of P. vivax episode. RESULTS The overall incidence rate of P. vivax was 7.4 episodes per 1000 person-years of observation. The study showed households closer to the lake Zeway and Bulbula river (potential mosquito breeding sites) were more at risk of P. vivax infection (incidence rate ratio (IRR): 1.33; 95% CI = 1.23-1.45). Furthermore, the age group under 5 years (IRR: 1.40, 95% CI = 1.10-1.79), the age group 5-14 years (IRR: 1.27, 95% CI = 1.03-1.57), households with less educated household head (IRR: 1.63, 95% CI = 1.10-2.44) and house roof made of thatch/leaf (IRR: 1.35, 95% CI = 1.11-1.65) were at higher risk for P. vivax. Similar explanatory variables such as distance from the breeding sites, age group (under 5 years but not 5-14 years old), educational status and type of housing were also found to be the predictors of P. falciparum incidence. CONCLUSION Households living closer to a mosquito breeding site, age group under 15 years, less educated household heads and thatch/leaf roof housing were the risk factor for P. vivax. The result of this study can be used for tailored interventions for malaria control and prevention by prioritizing those living close to potential mosquito breeding site, enhancing bed net use of children less than 15 years of age, and improving housing.
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Affiliation(s)
- Taye Gari
- School of Public Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia.
| | - Tarekegn Solomon
- School of Public Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia
| | - Bernt Lindtjørn
- School of Public Health, College of Medicine and Health Sciences, Hawassa University, Hawassa, Ethiopia.,Centre for International Health, University of Bergen, Bergen, Norway
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13
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Tilaye T, Tessema B, Alemu K. Malaria Infection is High at Transit and Destination Phases Among Seasonal Migrant Workers in Development Corridors of Northwest Ethiopia: A Repeated Cross-Sectional Study. Res Rep Trop Med 2021; 12:107-121. [PMID: 34079425 PMCID: PMC8165298 DOI: 10.2147/rrtm.s306001] [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: 02/15/2021] [Accepted: 04/24/2021] [Indexed: 12/03/2022] Open
Abstract
Purpose Malaria is a leading public health problem in Ethiopia. Every year, thousands of seasonal farm workers travel to farm corridors in Northwest Ethiopia and fall at risk of malaria infection. However, the magnitude of malaria infection and risk factors during harvest time were not well identified. This study aimed at estimating the prevalence and risk factors of malaria infection among seasonal migrant workers in Northwest Ethiopia. Methods A repeated cross-sectional study was conducted at transit and destination phases in Metema district from September 15, 2018 to October 30, 2019. Data were collected using a structured questionnaire. A capillary blood sample was collected to examine infection with malaria parasite using a microscope. A multivariate logistic regression technique was used to determine risk factors. Results The malaria prevalence at transit and destination phases among migrant workers was 13.5% (95% CI: 12.07–14.93%) and 18.7% (95% CI: 16.40–21.02%), respectively. The combined prevalence was 16.1% (95% CI: 14.67–17.63%). The odds of malaria infection among migrant workers at the destination phase was 1.5 (OR=1.5, 95% CI 1.167–1.846) times higher compared to the transit phase. Education (AOR=8.198; 95% CI: 4.318–15.564), knowledge of antimalarial drugs (AOR=2.4; 95% CI: 1.43–3.95), and use of long-lasting insecticidal nets (AOR=5.0; 95% CI: 3.34–4.43) were significantly associated with malaria infection at migration phases. Conclusion This study showed that the burden of malaria among seasonal migrant workers was high at transit and destination phases. Malaria prevalence was higher at the destination phase compared to the transit phase. A tailored malaria prevention intervention is needed including awareness creation, screening, treatment, repellent, and prophylaxis at both phases to reduce malaria infections.
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Affiliation(s)
- Tesfaye Tilaye
- Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Belay Tessema
- Department of Medical Microbiology, School of Biomedical and Medical Laboratory, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Kassahun Alemu
- Department of Epidemiology and Biostatistics, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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14
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Wagnew Y, Hagos T, Weldegerima B, Debie A. Willingness to Pay for Childhood Malaria Vaccine Among Caregivers of Under-Five Children in Northwest Ethiopia. CLINICOECONOMICS AND OUTCOMES RESEARCH 2021; 13:165-174. [PMID: 33758520 PMCID: PMC7979355 DOI: 10.2147/ceor.s299050] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Accepted: 02/26/2021] [Indexed: 11/23/2022] Open
Abstract
BACKGROUND Malaria, a protozoan disease caused by the genus Plasmodium, is responsible for serious illnesses and death across the world. RTS, S/AS01 (Mosquirix™) is a recombinant protein-based malaria vaccine valuable for the prevention and control of the disease. However, studies done so far on the willingness to pay (WTP) malaria vaccine have been inadequate to inform policy-makers. METHODS A community-based cross-sectional study was conducted to assess the WTP for childhood malaria vaccine and associated factors among caregivers of under-five children from February to April 2019 in West Dembia district. A multistage stratified systematic sampling technique was used, and the contingent valuation method was used to estimate caregivers' willingness to pay for the vaccine. AOR with 95% CI and less than 0.05 p-values were used to declare factors associated with WTP. RESULTS Overall, 60.6% (95% CI: 56.60, 64.40%) of caregivers of under-five children were WTP for the childhood malaria vaccine at a price of US$ 23.11 per full doses. Urban residence (AOR=1.78, 95% CI: 1.04, 3.04), educational status (AOR=3.27; 95% CI: 1.07, 9.94) and vaccination experience for children (AOR= 2.12; 95% CI: 1.29, 3.48) were positively associated with the WTP. WTP for the vaccine was higher among rich households (AOR=3.15; 95% CI: 1.90, 5.22), caregivers who had the previous history of malaria attack (AOR=2.62; 95% CI: 1.68, 4.08), households with fewer members (AOR=1.59; 95% CI: 1.06, 2.40), and families more knowledgeable about malaria prevention and control (AOR=3.56; 95% CI: 1.83, 6.93) compared with their counterparts. CONCLUSION The majority of the participants were WTP for the childhood malaria vaccine. A significant rise in willingness to purchase was observed at price below the profile price. Thus, it is of great value to policy-makers to understand the price sensitivity before setting the price of the vaccine.
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Affiliation(s)
- Yohannes Wagnew
- University of Gondar Comprehensive and Specialized Referral Hospital, University of Gondar, Gondar, Ethiopia
| | - Tsega Hagos
- Department of Health Systems and Policy, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Berhanemeskel Weldegerima
- Department of Pharmaceutics, School of Pharmacy, College of Medical and Health Sciences, University of Gondar, Gondar, Ethiopia
| | - Ayal Debie
- Department of Health Systems and Policy, Institute of Public Health, College of Medicine and Health Sciences, University of Gondar, Gondar, Ethiopia
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15
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Zerdo Z, Van Geertruyden JP, Massebo F, Biresaw G, Shewangizawu M, Tunje A, Chisha Y, Yohanes T, Bastiaens H, Anthierens S. Parents' perception on cause of malaria and their malaria prevention experience among school-aged children in Kutcha district, Southern Ethiopia; qualitative study. PLoS One 2020; 15:e0239728. [PMID: 33048941 PMCID: PMC7553332 DOI: 10.1371/journal.pone.0239728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2019] [Accepted: 09/11/2020] [Indexed: 11/19/2022] Open
Abstract
Introduction School-aged children become a highly vulnerable group for malaria, yet they are less likely to use malaria prevention interventions. Previous studies exploring perception on cause of malaria mainly focused on pregnant mothers or parents of children under age five years. Exploring parent’s perception on cause of malaria and their experiences on the prevention of malaria and associated challenges among school-aged children is important to develop a malaria prevention education package for school-aged children to reduce malaria and malaria related morbidities among school-aged children. Methods A descriptive qualitative study is conducted in Kutcha district by recruiting 19 parents of school-aged children for semi-structured interviews, 6 key informants and 6 focus group discussion which consists of parents, health development army and health extension workers. A semi-structured interview guide is used to guide the interview process. The collected data is analyzed thematically with a focus on the three major areas of concern: perceived cause of malaria, experience of malaria prevention and challenges of bed net use for prevention of malaria. Results Five causes of malaria were identified, namely hunger, mosquito bite, exposure to hot sunshine, poor sanitation and hygiene and eating some sweet foods and unripe maize. Participants perceived that eating sweet foods and unripe maize lead to enlargement of the spleen that ends in malaria while poor hygiene and sanitation leads to either development of the ova of mosquito and the landing of the housefly to contaminate food for consumption. The experiences of malaria prevention were largely influenced by their perceived cause of malaria. The malaria prevention measures undertaken by parents were vectors control measures, homemade herbal remedies and restricting children from eating sweet foods. The challenges of malaria prevention by using bed nets were related to a negative attitude, sleeping behaviors of children; use of bed nets for unintended purposes, shortage of bed nets and delays in the distribution of bed nets. Conclusion There were misconceptions about the cause of malaria and associated experiences of malaria prevention. Control of malaria among school-aged children need health education targeting the challenges and correcting identified misconceptions by parents in Kutcha district and in other similar settings.
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Affiliation(s)
- Zerihun Zerdo
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
- Global Health Institute, Antwerp University, Antwerp, Belgium
- * E-mail:
| | | | - Fekadu Massebo
- Department of Biology, College of Natural Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Gelila Biresaw
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Misgun Shewangizawu
- Department of public health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Abayneh Tunje
- Department of public health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Yilma Chisha
- Department of public health, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Tsegaye Yohanes
- Department of Medical Laboratory Science, College of Medicine and Health Sciences, Arba Minch University, Arba Minch, Ethiopia
| | - Hilde Bastiaens
- Department of Family Medicine and Population Health, University of Antwerp, Antwerp, Belgium
| | - Sibyl Anthierens
- Department of Family Medicine and Population Health, University of Antwerp, Antwerp, Belgium
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16
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Aikambe JN, Mnyone LL. Retrospective Analysis of Malaria Cases in a Potentially High Endemic Area of Morogoro Rural District, Eastern Tanzania. Res Rep Trop Med 2020; 11:37-44. [PMID: 32607048 PMCID: PMC7297450 DOI: 10.2147/rrtm.s254577] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2020] [Accepted: 05/25/2020] [Indexed: 11/23/2022] Open
Abstract
Background Malaria is increasingly characterized by appreciable fine-scale variability in ecology and topography, and it is likely that we are missing some salient foci with unprecedented malaria transmission intensity in different parts of Tanzania. Therefore, efforts aimed at identifying area-specific malaria situation and intervening are needed to preserve the realized health gains and achieve elimination. Mkuyuni and Kiroka, adjacent wards within Morogoro Rural District, are purported to form one of such foci. Patients and Methods A retrospective study was conducted to determine six-year (2014-2019) malaria prevalence rates based on outpatients and laboratory registers obtained from two health facilities, one per ward, carrying out diagnosis of malaria either through microscopy or malaria rapid diagnostic test (mRDT). These data were checked for completeness before carrying out statistical analysis. Results Overall, 35,386 (46.19%) out of 76,604 patients were positive for malaria. The average proportion of malaria cases was significantly higher in Mkuyuni (51.23%; n=19,438) than Kiroka (41.21%; n = 15,938) (P <0.001). Females were more affected than males (P <0.001);, and irrespective of the sex, most malaria cases were recorded in children <5 years of age (P <0.001) except at Mkuyuni. Malaria was recorded virtually all year round; however, the highest proportion of cases was recorded in April and July (P <0.001). Conclusion This study revealed high malaria endemicity in Mkuyuni and Kiroka, with prevalence rate as high as 60.98%, which is far higher than the overall national average prevalence of 9%. More studies are needed in these and other putatively high endemic foci in Tanzania in order to inform the future course of action in disease surveillance and control.
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Affiliation(s)
- Joseph N Aikambe
- Department of Microbiology, Parasitology and Biotechnology, College of Veterinary Medicine and Biomedical Sciences, Sokoine University of Agriculture, Morogoro, Tanzania.,Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania
| | - Ladslaus L Mnyone
- Pest Management Centre, Sokoine University of Agriculture, Morogoro, Tanzania.,School of Public Health, Faculty of Health Sciences, University of the Witwatersrand, Johannesburg, South Africa
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17
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Spatiotemporal clustering of malaria in southern-central Ethiopia: A community-based cohort study. PLoS One 2019; 14:e0222986. [PMID: 31568489 PMCID: PMC6768540 DOI: 10.1371/journal.pone.0222986] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2019] [Accepted: 09/11/2019] [Indexed: 01/08/2023] Open
Abstract
Introduction Understanding the spatiotemporal clustering of malaria transmission would help target interventions in settings of low malaria transmission. The aim of this study was to assess whether malaria infections were clustered in areas with long-lasting insecticidal nets (LLINs) alone, indoor residual spraying (IRS) alone, or a combination of LLINs and IRS interventions, and to determine the risk factors for the observed malaria clustering in southern-central Ethiopia. Methods A cohort of 34,548 individuals residing in 6,071 households was followed for 121 weeks, from October 2014 to January 2017. Both active and passive case detection mechanisms were used to identify clinical malaria episodes, and there were no geographic heterogeneity in data collection methods. Using SaTScan software v 9.4.4, a discrete Poisson model was used to identify high rates of spatial, temporal, and spatiotemporal malaria clustering. A multilevel logistic regression model was fitted to identify predictors of spatial malaria clustering. Results The overall incidence of malaria was 16.5 per 1,000 person-year observations. Spatial, temporal, and spatiotemporal clustering of malaria was detected in all types of malaria infection (P. falciparum, P. vivax, or mixed). Spatial clustering was identified in all study arms: for LLIN + IRS arm, a most likely cluster size of 169 cases in 305 households [relative risk (RR) = 4.54, P<0.001]; for LLIN alone arm a cluster size of 88 cases in 103 households (RR = 5.58, P<0.001); for IRS alone arm a cluster size of 58 cases in 50 households (RR = 7.15, P<0.001), and for control arm a cluster size of 147 cases in 377 households (RR = 2.78, P<0.001). Living 1 km closer to potential vector breeding sites increased the odds of being in spatial clusters by 41.32 fold (adjusted OR = 41.32, 95% CI = 3.79–138.89). Conclusions The risk of malaria infection varied significantly between kebeles, within kebeles, and even among households in areas targeted for different types of malaria control interventions in low malaria transmission setting. The results of this study can be used in planning and implementation of malaria control strategies at micro-geographic scale. Trial registration PACT R2014 11000 882128 (8 September 2014).
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18
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Kenea O, Balkew M, Tekie H, Deressa W, Loha E, Lindtjørn B, Overgaard HJ. Impact of combining indoor residual spraying and long-lasting insecticidal nets on Anopheles arabiensis in Ethiopia: results from a cluster randomized controlled trial. Malar J 2019; 18:182. [PMID: 31126286 PMCID: PMC6534825 DOI: 10.1186/s12936-019-2811-1] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2018] [Accepted: 05/15/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Indoor residual house spraying (IRS) and long-lasting insecticidal nets (LLINs) are the key front-line malaria vector interventions against Anopheles arabiensis, the sole primary malaria vector in Ethiopia. Universal coverage of both interventions has been promoted and there is a growing demand in combinations of interventions for malaria control and elimination. This study compared the impact on entomological outcomes of combining IRS and LLINs with either intervention alone in Adami Tullu district, south-central Ethiopia. The epidemiological outcomes were recently published on a separate paper. METHODS This factorial, cluster-randomized, controlled trial randomized villages to four study arms: IRS + LLIN, IRS, LLIN, and control. LLINs (PermaNet 2.0) were provided free of charge. IRS with propoxur was applied before the main malaria transmission season in 2014, 2015 and 2016. Adult mosquitoes were collected in randomly selected villages in each arm using CDC light trap catch (LTC) set close to a sleeping person, pyrethrum spray catch (PSC), and artificial pit shelter (PIT), for measuring mosquito host-seeking density (HSD), indoor resting density (IRD), and outdoor resting density (ORD), respectively. Human landing catch (HLC) was performed in a sub-set of villages to monitor An. arabiensis human biting rates (HBR). Mean vector densities and HBR were compared among study arms using incidence rate ratio (IRR) calculated by negative binomial regression. RESULTS There were no significant differences in mean densities (HSD, IRD, ORD) and HBR of An. arabiensis between the IRS + LLIN arm and the IRS arm (p > 0.05). However, mean HSD, IRD, ORD, and HBR were significantly lower in the IRS + LLIN arm than in the LLIN alone arm (p < 0.05). All An. arabiensis tested for malaria infection were negative for Plasmodium species. For this reason, the entomological inoculation rate could not be determined. CONCLUSIONS The IRS + LLIN were as effective as IRS alone in reducing densities and HBR of An. arabiensis. However, the effectiveness of the two interventions combined was higher than LLINs alone in reducing densities and HBR of the vector. Added impact of the combination intervention against malaria infectivity rates of An. arabiensis compared to either intervention alone remains unknown and warrants further research. Trial registration PACTR201411000882128. Registered 8 September 2014, https://trialsjournal.biomedcentral.com/articles/10.1186/s13063-016-1154-2.
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Affiliation(s)
- Oljira Kenea
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia. .,Department of Biology, Wollega University, Nekemte, Ethiopia.
| | - Meshesha Balkew
- Akililu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Habte Tekie
- Department of Zoological Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Wakgari Deressa
- Department of Preventive Medicine, School of Public Health, College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia
| | - Eskindir Loha
- School of Public and Environmental Health, Hawassa University, Hawassa, Ethiopia
| | - Bernt Lindtjørn
- Centre for International Health, University of Bergen, Bergen, Norway
| | - Hans J Overgaard
- Faculty of Science and Technology, Norwegian University of Life Sciences, Ås, Norway
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19
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Loha E, Deressa W, Gari T, Balkew M, Kenea O, Solomon T, Hailu A, Robberstad B, Assegid M, Overgaard HJ, Lindtjørn B. Long-lasting insecticidal nets and indoor residual spraying may not be sufficient to eliminate malaria in a low malaria incidence area: results from a cluster randomized controlled trial in Ethiopia. Malar J 2019; 18:141. [PMID: 30999957 PMCID: PMC6471954 DOI: 10.1186/s12936-019-2775-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 04/11/2019] [Indexed: 12/22/2022] Open
Abstract
Background Conflicting results exist on the added benefit of combining long-lasting insecticidal nets (LLINs) with indoor residual spraying (IRS) to control malaria infection. The main study objective was to evaluate whether the combined use of LLINs and IRS with propoxur provides additional protection against Plasmodium falciparum and/or Plasmodium vivax among all age groups compared to LLINs or IRS alone. Methods This cluster-randomized, controlled trial was conducted in the Rift Valley area of Ethiopia from September 2014 to January 2017 (121 weeks); 44 villages were allocated to each of four study arms: LLIN + IRS, IRS, LLIN, and control. Each week, 6071 households with 34,548 persons were surveyed by active and passive case detection for clinical malaria. Primary endpoints were the incidence of clinical malaria and anaemia prevalence. Results During the study, 1183 malaria episodes were identified, of which 55.1% were P. falciparum and 25.3% were P. vivax, and 19.6% were mixed infections of P. falciparum and P. vivax. The overall malaria incidence was 16.5 per 1000 person-years of observation time (PYO), and similar in the four arms with 17.2 per 1000 PYO in the LLIN + IRS arm, 16.1 in LLIN, 17.0 in IRS, and 15.6 in the control arm. There was no significant difference in risk of anaemia among the trial arms. Conclusions The clinical malaria incidence and anaemia prevalence were similar in the four study groups. In areas with low malaria incidence, using LLINs and IRS in combination or alone may not eliminate malaria. Complementary interventions that reduce residual malaria transmission should be explored in addition to LLINs and IRS to further reduce malaria transmission in such settings. Trial registration PACTR201411000882128 (08 September 2014) Electronic supplementary material The online version of this article (10.1186/s12936-019-2775-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Eskindir Loha
- School of Public Health, Hawassa University, Hawassa, Ethiopia
| | - Wakgari Deressa
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia
| | - Taye Gari
- School of Public Health, Hawassa University, Hawassa, Ethiopia.,Centre for International Health, University of Bergen, Bergen, Norway
| | - Meshesha Balkew
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Oljira Kenea
- Aklilu Lemma Institute of Pathobiology, Addis Ababa University, Addis Ababa, Ethiopia
| | - Tarekegn Solomon
- School of Public Health, Hawassa University, Hawassa, Ethiopia.,Centre for International Health, University of Bergen, Bergen, Norway
| | - Alemayehu Hailu
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia.,Centre for International Health, University of Bergen, Bergen, Norway
| | - Bjarne Robberstad
- Centre for International Health, University of Bergen, Bergen, Norway
| | - Meselech Assegid
- Department of Preventive Medicine, School of Public Health, Addis Ababa University, Addis Ababa, Ethiopia.,Centre for International Health, University of Bergen, Bergen, Norway
| | | | - Bernt Lindtjørn
- Centre for International Health, University of Bergen, Bergen, Norway.
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