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Di Santi SMF. The silent threat of submicroscopic Plasmodium infections during pregnancy. Lancet Glob Health 2023; 11:e991-e992. [PMID: 37276879 DOI: 10.1016/s2214-109x(23)00249-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Accepted: 05/22/2023] [Indexed: 06/07/2023]
Affiliation(s)
- Silvia Maria Fátima Di Santi
- Infectious Diseases Department, University Of São Paulo, 05403-000 São Paulo, Brazil; Malaria Reference Laboratory, Instituto Adolfo Lutz, São Paulo, Brazil.
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van Eijk AM, Stepniewska K, Hill J, Taylor SM, Rogerson SJ, Cottrell G, Chico RM, Gutman JR, Tinto H, Unger HW, Yanow SK, Meshnick SR, Ter Kuile FO, Mayor A. Prevalence of and risk factors for microscopic and submicroscopic malaria infections in pregnancy: a systematic review and meta-analysis. Lancet Glob Health 2023; 11:e1061-e1074. [PMID: 37276878 PMCID: PMC10880462 DOI: 10.1016/s2214-109x(23)00194-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2022] [Revised: 04/05/2023] [Accepted: 04/11/2023] [Indexed: 06/07/2023]
Abstract
BACKGROUND Malaria infections during pregnancy can cause adverse birth outcomes, yet many infections are undetected by microscopy. We aimed to describe the epidemiology of submicroscopic malaria infections in pregnant women in Asia, the Americas, and Africa using aggregated and individual participant data (IPD). METHODS For this systematic review and meta-analysis, studies (published Jan 1, 1997 to Nov 10, 2021) with information on both microscopic and submicroscopic infections during pregnancy from Asia, the Americas, or Africa, identified in the Malaria-in-Pregnancy Library, were eligible. Studies (or subgroups or study groups) that selected participants on the basis of the presence of fever or a positive blood smear were excluded to avoid selection bias. We obtained IPD (when available) and aggregated data. Estimates of malaria transmission intensity and sulfadoxine-pyrimethamine resistance, matched by study location and year, were obtained using publicly available data. One-stage multivariable logit and multinomial models with random intercepts for study site were used in meta-analysis to assess prevalence of and risk factors for submicroscopic infections during pregnancy and at delivery. This study is registered with PROSPERO, number CRD42015027342. FINDINGS The search identified 87 eligible studies, 68 (78%) of which contributed to the analyses. Of these 68 studies, 45 (66%) studies contributed IPD (48 869 participants) and 23 (34%) studies contributed aggregated data (11 863 participants). During pregnancy, median prevalence estimates were 13·5% (range 0·0-55·9, 66 substudies) for submicroscopic and 8·0% (0·0-50·6, 66 substudies) for microscopic malaria. Among women with positive Plasmodium nucleic acid amplification tests (NAATs), the median proportion of submicroscopic infections was 58·7% (range 0·0-100); this proportion was highest in the Americas (73·3%, 0·0-100), followed by Asia (67·2%, 36·4-100) and Africa (56·5%, 20·5-97·7). In individual patient data analysis, compared with women with no malaria infections, those with submicroscopic infections were more likely to present with fever in Africa (adjusted odds ratio 1·32, 95% CI 1·02-1·72; p=0·038) but not in other regions. Among women with NAAT-positive infections in Asia and the Americas, Plasmodium vivax infections were more likely to be submicroscopic than Plasmodium falciparum infections (3·69, 2·45-5·54; p<0·0001). Risk factors for submicroscopic infections among women with NAAT-positive infections in Africa included older age (age ≥30 years), multigravidity, and no HIV infection. INTERPRETATION During pregnancy, submicroscopic infections are more common than microscopic infections and are associated with fever in Africa. Malaria control in pregnancy should target both microscopic and submicroscopic infections. FUNDING Bill & Melinda Gates Foundation through the Worldwide Antimalarial Resistance Network.
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Affiliation(s)
- Anna Maria van Eijk
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK.
| | - Kasia Stepniewska
- Centre for Tropical Medicine and Global Health, Nuffield Department of Clinical Medicine, University of Oxford, Oxford, UK
| | - Jenny Hill
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Steve M Taylor
- Division of Infectious Diseases and Duke Global Health Institute, Duke University, Durham, NC, USA
| | - Stephen J Rogerson
- Department of Infectious Diseases, Doherty Institute, The University of Melbourne, Melbourne, VIC, Australia
| | | | - R Matthew Chico
- Department of Disease Control, London School of Hygiene & Tropical Medicine, London, UK
| | - Julie R Gutman
- Malaria Branch, Division of Parasitic Diseases and Malaria, Center for Global Health, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Halidou Tinto
- Institut de Recherche en Sciences de la Sant-Unité de Recherche Clinique de Nanoro, Ouagadougou, Burkina Faso
| | - Holger W Unger
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK; Menzies School of Health Research, Charles Darwin University, Darwin, NT, Australia
| | - Stephanie K Yanow
- School of Public Health, Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, AB, Canada
| | - Steven R Meshnick
- Institute for Global Health and Infectious Diseases, School of Medicine, University of North Carolina, Chapel Hill, NC, USA
| | - Feiko O Ter Kuile
- Department of Clinical Sciences, Liverpool School of Tropical Medicine, Liverpool, UK
| | - Alfredo Mayor
- ISGlobal, Barcelona Institute for Global Health, Hospital Clínic-Universitat de Barcelona, Barcelona, Spain; Centro de Investigação em Saúde de Manhiça, Maputo, Mozambique
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Kartal L, Mueller I, Longley RJ. Using Serological Markers for the Surveillance of Plasmodium vivax Malaria: A Scoping Review. Pathogens 2023; 12:791. [PMID: 37375481 DOI: 10.3390/pathogens12060791] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/29/2023] [Accepted: 05/29/2023] [Indexed: 06/29/2023] Open
Abstract
The utilisation of serological surveillance methods for malaria has the potential to identify individuals exposed to Plasmodium vivax, including asymptomatic carriers. However, the application of serosurveillance varies globally, including variations in methodology and transmission context. No systematic review exists describing the advantages and disadvantages of utilising serosurveillance in various settings. Collation and comparison of these results is a necessary first step to standardise and validate the use of serology for the surveillance of P. vivax in specific transmission contexts. A scoping review was performed of P. vivax serosurveillance applications globally. Ninety-four studies were found that met predefined inclusion and exclusion criteria. These studies were examined to determine the advantages and disadvantages of serosurveillance experienced in each study. If studies reported seroprevalence results, this information was also captured. Measurement of antibodies serves as a proxy by which individuals exposed to P. vivax may be indirectly identified, including those with asymptomatic infections, which may be missed by other technologies. Other thematic advantages identified included the ease and simplicity of serological assays compared to both microscopy and molecular diagnostics. Seroprevalence rates varied widely from 0-93%. Methodologies must be validated across various transmission contexts to ensure the applicability and comparability of results. Other thematic disadvantages identified included challenges with species cross-reactivity and determining changes in transmission patterns in both the short- and long-term. Serosurveillance requires further refinement to be fully realised as an actionable tool. Some work has begun in this area, but more is required.
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Affiliation(s)
- Lejla Kartal
- School of Population and Global Health, The University of Melbourne, Parkville 3010, Australia
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
| | - Ivo Mueller
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville 3010, Australia
| | - Rhea J Longley
- Population Health and Immunity, The Walter and Eliza Hall Institute of Medical Research, Parkville 3052, Australia
- Department of Medical Biology, The University of Melbourne, Parkville 3010, Australia
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Mapping and characterizing areas with high levels of malaria in pregnancy in Brazil: A spatiotemporal analysis. LANCET REGIONAL HEALTH. AMERICAS 2022; 12:100285. [PMID: 36776427 PMCID: PMC9903888 DOI: 10.1016/j.lana.2022.100285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Background Malaria in pregnancy (MiP) is a public health problem in the Brazilian Amazon region that requires special attention due to associated serious adverse consequences, such as low birth weight, increased prematurity and spontaneous abortion rates. In Brazil, there have been no comprehensive epidemiological studies of MiP. In this study, we aimed to explore the spatial and spatiotemporal patterns of MiP in Brazil and epidemiologically characterize this population of pregnant women over a period of 15 years. Methods We performed a national-scale ecological analysis using a Bayesian space-time hierarchical model to estimate the incidence rates of MiP between 1 January 2004 and 31 December 2018. We mapped the high-incidence clusters among pregnant women aged 10-49 years old using a Poisson model, and we characterized the population based on data from the Epidemiological Surveillance Information System for Malaria (SIVEP-Malaria). Findings We consolidated the data of 61,833 women with MiP in Brazil. Our results showed a reduction of 50·1% (95% CI: 47·3 to 52·9) in the number of malaria cases over the period analysed, with Plasmodium vivax malaria having the highest incidence. MiP was widely distributed throughout the Amazon region, and spatial and spatiotemporal analyses revealed statistically significant clusters in some municipalities of Amazonas, Acre, Rondônia and Pará. In addition, we observed that younger pregnant women had a higher risk of infection, and the administration of appropriate treatment requires more attention. Interpretation This nationwide study provides robust evidence that, despite the reduction in the number of MiP cases in the country, it remains a serious public health problem, especially for young pregnant women. Our analyses highlight focus areas for strengthening interventions to control and eliminate MiP. Funding FAPESP and CNPq - Brazil.
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Jain K, Gupta P, Balodhi A, Deeba F, Salam N. Prevalence of Pregnancy Associated Malaria in India. Front Glob Womens Health 2022; 3:832880. [PMID: 35692947 PMCID: PMC9178198 DOI: 10.3389/fgwh.2022.832880] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/28/2022] [Indexed: 12/03/2022] Open
Abstract
Malaria in pregnancy is a major public health concern. It results in impaired maternal health and adversely effects fetal and perinatal outcomes. The present systematic review was conducted to assess the prevalence, distribution and adverse pregnancy outcomes in malaria infected females in India. A comprehensive search and review of PubMed and Web of Science based on PRISMA guidelines was carried out to find articles reporting prevalence of malaria in pregnant women from India. Data from 16 studies were analyzed and prevalence of malaria among pregnant women in India was found to be 11.4 % (95 % CI: 7.3, 16.3). Prevalence of malaria among asymptomatic and symptomatic pregnant women was found to be 10.62% (95% CI: 6.05, 16.23) and 13.13% (95% CI: 7.2, 20.52), respectively. P. falciparum and P. vivax were both reported with in the same population. The geospatial distribution of malaria in pregnancy spanned over nine very populous states of India. The review also reported severe maternal and perinatal outcomes. Given the seriousness of malaria in pregnant women and its effects on the fetus and new-born, a stringent district wise guideline for early detection and prophylaxis in regions identified in this review will help in its better control.
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Affiliation(s)
- Khushi Jain
- Department of Microbiology, Central University of Punjab, Bathinda, India
| | - Palak Gupta
- Department of Microbiology, Central University of Punjab, Bathinda, India
| | - Ashutosh Balodhi
- Department of Microbiology, Central University of Punjab, Bathinda, India
| | - Farah Deeba
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi, India
| | - Nasir Salam
- Department of Microbiology, Central University of Punjab, Bathinda, India
- *Correspondence: Nasir Salam
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Farinas MDLRN, Aschar M, Costa-Nascimento MDJ, Di Santi SM. An algorithm based on molecular protocols to improve the detection of Plasmodium in autochthonous malarial areas in the Atlantic Forest biome. Rev Inst Med Trop Sao Paulo 2022; 64:e18. [PMID: 35239862 PMCID: PMC8901118 DOI: 10.1590/s1678-9946202264018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 01/31/2022] [Indexed: 11/21/2022] Open
Abstract
Malaria is the most important vector-borne disease in the world and a challenge for control programs. In Brazil, 99% of cases occur in the Amazon region. In the extra-Amazonian region, a non-endemic area, epidemiological surveillance focuses on imported malaria and on autochthonous outbreaks, including cases with mild symptoms and low parasitemia acquired in the Atlantic Forest biome. In this scenario, cases are likely to be underreported, since submicroscopic parasitemias are not detected by thick blood smear, considered the reference test. Molecular tests are more sensitive, detecting asymptomatic individuals and mixed infections. The aim of this study was to propose a more efficient alternative to detect asymptomatic individuals living in areas of low malaria endemicity, as they are reservoirs of Plasmodium that maintain transmission locally. In total, 955 blood samples from residents of 16 municipalities with autochthonous malaria outbreaks in the Sao Paulo State were analyzed; 371 samples were collected in EDTA tubes and 584 in filter paper. All samples were initially screened by a genus-specific qPCR targeting ssrRNA genes (limit of detection of 1 parasite/µL). Then, positive samples were subjected to a nested PCR targeting ssrRNA and dihydrofolate reductase-thymidylate synthase genes (limit of detection of 10 parasites/µL) to determine Plasmodium species. The results showed a statistically significant difference (K = 0.049; p < 0.0001) between microscopy positivity (6.9%) and qPCR (22.9%) for EDTA-blood samples. Conversely, for samples collected in filter paper, no statistical difference was observed, with 2.6% positivity by thick blood smear and 3.1% for qPCR (K = 0.036; p = 0.7). Samples positive by qPCR were assayed by a species-specific nested PCR that was in turn positive in 26% of samples (16 P. vivax and 4 P. malariae ). The results showed that molecular protocols applied to blood samples from residents in areas with autochthonous transmission of malaria were useful to detect asymptomatic patients who act as a source of transmission. The results showed that the genus-specific qPCR was useful for screening positives, with the subsequent identification of species by nested PCR. Additional improvements, such as standardization of blood plotting on filter paper and a more sensitive protocol for species determination, are essential. The qPCR-based algorithm for screening positives followed by nested PCR will contribute to more efficient control of malaria transmission, offering faster and more sensitive tools to detect asymptomatic Plasmodium reservoirs.
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Affiliation(s)
| | | | | | - Silvia Maria Di Santi
- Universidade de São Paulo, Brazil; Secretaria da Saúde de São Paulo, Brazil; Universidade de São Paulo, Brazil
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Domingues W, Dos Santos EH, Yamamoto L, Di Santi SM, Kanunfre KA, Okay TS. Single-round multiplex PCR with species-specific mitochondrial primers of P. falciparum, P. vivax/P. simium and P. malariae/P. brasilianum: Comparison with standard techniques. J Microbiol Methods 2021; 193:106398. [PMID: 34953974 DOI: 10.1016/j.mimet.2021.106398] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 12/17/2021] [Accepted: 12/17/2021] [Indexed: 11/19/2022]
Abstract
A single-round multiplex PCR (mPCR) with species-specific primers (SSP) of three mitochondrial genes of Plasmodium, namely COX I, COX III and CYT B, was compared to microscopy and 18S rRNA semi-nested PCR, nested-PCR and Real Time PCRs (*PCRs). Each parasite has between 20 and 150 mitochondria and each mitochondria has one copy of each target gene, while 18S rRNA gene is repeated 4 to 8 times. The specificity of mPCR was assessed by testing Plasmodium from rodents and birds, parasites responsible for other endemic diseases in the country such as schistosomiasis, Chagas disease and leishmaniasis in addition to microorganisms that, like Plasmodium, can cause anemia (Bartonella henselae, Babesia vogeli, Rickettsia vini). No cross-reactions were detected. From a total of 149 specimens from suspected cases of malaria were tested, 97 were positive by microscopy (49 P. falciparum, 38 P. vivax, 6 P. malariae, 4 P. falciparum/P. vivax- mixed infections) and 52 were negative; 148 samples were positive by *PCRs (49 P. falciparum, 53 P. vivax, 7 P. malariae and 39 mixed infections) and one was negative; 146 were positive by mPCR (49 P. falciparum, 56 P. vivax, 9 P. malariae and 32 mixed infections) and three were negative. The comparison of groups found statistically significant differences between microscopy vs.*PCRs or vs. mPCR (p-values <0.0001), but no difference was found between mPCR vs. *PCRs (p=0.946). The agreement in the identification of Plasmodium species was only regular, with Kappa indices of 0.407 (microscopy vs. *PCRs), 0.433 (microscopy vs. mPCR) and 0.558 (*PCRs vs. mPCR). In conclusion, the diagnostic performance of mPCR was comparable to those of *PCRs, and superior to microscopy, although the identification of Plasmodium species showed many disagreements. In conclusion, a sensitive and specific one-round SSP multiplex PCR, capable of simultaneously detecting and identifying P. falciparum, P. vivax/P. simium and P. malariae/P. brasilianum may be useful in resource-constrained countries where quantitative amplifications are not yet fully accessible.
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Affiliation(s)
- Wilson Domingues
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Emilly Henrique Dos Santos
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Lidia Yamamoto
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil
| | - Silvia Maria Di Santi
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil; Núcleo de Estudos em Malária, Superintendência de Controle de Endemias, Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, São Paulo, Brazil
| | - Kelly Aparecida Kanunfre
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil; LIM 48, Departamento de Moléstias Infecciosas e Parasitárias, Universidade de São Paulo, Faculdade de Medicina, São Paulo, São Paulo, Brazil
| | - Thelma Suely Okay
- Laboratório de Soroepidemiologia e Imunobiologia, Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, São Paulo, Brazil; Departamento de Pediatria, Faculdade de Medicina, Universidade de São Paulo, Brazil.
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Seijas-Chávez JA, Nolan MS, Lynn MK, da Rocha MJF, da Costa Araújo M, Fonseca FLA, Laporta GZ. Causal effects on low Apgar at 5-min and stillbirth in a malaria maternal-fetal health outcome investigation: a large perinatal surveillance study in the Brazilian Amazon. Malar J 2021; 20:444. [PMID: 34823521 PMCID: PMC8614005 DOI: 10.1186/s12936-021-03981-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Accepted: 11/12/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Malaria elimination in Brazil poses several challenges, including the control of Plasmodium falciparum foci and the hidden burden of Plasmodium vivax in pregnancy. Maternal malaria and fetal health outcomes were investigated with a perinatal surveillance study in the municipality of Cruzeiro do Sul, Acre state, Brazilian Amazon. The research questions are: what are the causal effects of low birth weight on low Apgar at 5-min and of perinatal anaemia on stillbirth? METHODS From November 2018 to October 2019, pregnant women of ≥ 22 weeks or puerperal mothers, who delivered at the referral maternity hospital (Juruá Women and Children's Hospital), were recruited to participate in a malaria surveillance study. Clinical information was obtained from a questionnaire and abstracted from medical reports. Haemoglobin level and presence of malarial parasites were tested by haematology counter and light microscopy, respectively. Low Apgar at 5-min and stillbirth were the outcomes analysed in function of clinical data and epidemiologic risk factors for maternal malaria infection using both a model of additive and independent effects and a causal model with control of confounders and use of mediation. RESULTS In total, 202 (7.2%; N = 2807) women had malaria during pregnancy. Nearly half of malaria infections during pregnancy (n = 94) were P. falciparum. A total of 27 women (1.03%; N = 2632) had perinatal malaria (19 P. vivax and 8 P. falciparum). Perinatal anaemia was demonstrated in 1144 women (41.2%; N = 2779) and low birth weight occurred in 212 newborns (3.1%; N = 2807). A total of 75 newborns (2.7%; N = 2807) had low (< 7) Apgar scores at 5-min., and stillbirth occurred in 23 instances (30.7%; n = 75). Low birth weight resulted in 7.1 higher odds of low Apgar at 5-min (OR = 7.05, 95% CI 3.86-12.88, p < 0.001) modulated by living in rural conditions, malaria during pregnancy, perinatal malaria, and perinatal anaemia. Stillbirth was associated with perinatal anaemia (OR = 2.56, 95% CI 1.02-6.42, p = 0.0444) modulated by living in rural conditions, falciparum malaria during pregnancy, perinatal malaria, and perinatal fever. CONCLUSIONS While Brazil continues its path towards malaria elimination, the population still faces major structural problems, including substandard living conditions. Here malaria infections on pregnant women were observed having indirect effects on fetal outcomes, contributing to low Apgar at 5-min and stillbirth. Finally, the utility of employing multiple statistical analysis methods to validate consistent trends is vital to ensure optimal public health intervention designs.
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Affiliation(s)
- Julio Abel Seijas-Chávez
- Centro Universitário FMABC, Fundação ABC, Santo André, SP, Brazil
- Hospital da Mulher e da Criança do Juruá (HMCJ), Cruzeiro do Sul, AC, Brazil
| | - Melissa S Nolan
- Laboratory of Vector-Borne and Parasitic Diseases, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA.
| | - Mary K Lynn
- Laboratory of Vector-Borne and Parasitic Diseases, Arnold School of Public Health, University of South Carolina, Columbia, SC, USA
| | | | - Muana da Costa Araújo
- Vigilância Entomológica da Secretaria Municipal de Saúde, Cruzeiro do Sul, AC, Brazil
| | - Fernando Luiz Affonso Fonseca
- Centro Universitário FMABC, Fundação ABC, Santo André, SP, Brazil
- Departamento de Farmácia, Universidade Federal de São Paulo (UNIFESP), Diadema, SP, Brazil
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Aschar M, Levi JE, Farinas MLRN, Montebello SC, Mendrone-Junior A, Di Santi SM. The hidden Plasmodium malariae in blood donors: a risk coming from areas of low transmission of malaria. Rev Inst Med Trop Sao Paulo 2020; 62:e100. [PMID: 33331519 PMCID: PMC7748032 DOI: 10.1590/s1678-9946202062100] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Accepted: 11/30/2020] [Indexed: 11/23/2022] Open
Abstract
Malaria is an infectious vector-borne disease with other important routes of
transmission, such as blood transfusion and organ/tissue transplantation, due to
asymptomatic reservoirs of Plasmodium presenting with low
parasitemia. Reports of transfusion-transmitted malaria have shown that in
immunosuppressed recipients, infections can be fatal if they are not diagnosed
and timely treated. All Plasmodium species can survive on blood
components at temperatures from 2 to 6 °C for some days or even weeks. This
report describes two candidates for blood donation harboring
Plasmodium, infected in an area considered non-endemic.
Blood samples were collected from donors who attended a blood bank in Sao Paulo
and tested by microscopy, qPCR for Plasmodium genus-specific
amplification, targeting the parasite 18S ribosomal subunit gene and a multiplex
qPCR based on mtDNA of the five species. Under microscopy, only structures
resembling Plasmodium were observed. The qPCR whose standard
curve tested parasites varying from 2 to 0.1 parasites/ µL, showed the presence
of Plasmodium DNA in the two blood donors, as did the multiplex
qPCR that revealed the presence of P. malariae. The prevalence
of positive donors varies according to the level of transmission, ranging from
0.7 to 55% in endemic areas. In non-endemic regions, prevalences are lower,
however, transfusion malaria can evolve to severe cases, due to the lack of
suspicion of this transmission route. Asymptomatic donors from low transmission
regions pose a risk to blood banks, with particular emphasis on those located in
areas with malaria elimination goals.
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Affiliation(s)
- Mariana Aschar
- Universidade de São Paulo, Faculdade de Medicina, Departamento de Moléstias Infecciosas e Parasitárias, São Paulo, São Paulo, Brazil
| | - José Eduardo Levi
- Universidade de São Paulo, Faculdade de Medicina, Departamento de Moléstias Infecciosas e Parasitárias, São Paulo, São Paulo, Brazil.,Universidade de São Paulo, Instituto de Medicina Tropical de São Paulo, Laboratório de Virologia, São Paulo, São Paulo, Brazil
| | - Maria L R N Farinas
- Universidade de São Paulo, Faculdade de Medicina, Departamento de Moléstias Infecciosas e Parasitárias, São Paulo, São Paulo, Brazil
| | - Sandra C Montebello
- Secretaria da Saúde de São Paulo, Fundação Pró-Sangue Hemocentro de São Paulo, São Paulo, São Paulo, Brazil
| | - Alfredo Mendrone-Junior
- Secretaria da Saúde de São Paulo, Fundação Pró-Sangue Hemocentro de São Paulo, São Paulo, São Paulo, Brazil
| | - Silvia Maria Di Santi
- Universidade de São Paulo, Faculdade de Medicina, Departamento de Moléstias Infecciosas e Parasitárias, São Paulo, São Paulo, Brazil.,Secretaria da Saúde de São Paulo, Superintendência de Controle de Endemias, Núcleo de Estudos em Malária, São Paulo, São Paulo, Brazil.,Universidade de São Paulo, Instituto de Medicina Tropical de São Paulo, São Paulo, São Paulo, Brazil
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Malaria in Pregnancy in Endemic Regions of Colombia: High Frequency of Asymptomatic and Peri-Urban Infections in Pregnant Women with Malaria. Infect Dis Obstet Gynecol 2020; 2020:2750258. [PMID: 32884230 PMCID: PMC7455813 DOI: 10.1155/2020/2750258] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Revised: 04/13/2020] [Accepted: 04/30/2020] [Indexed: 11/17/2022] Open
Abstract
Background Malaria in pregnancy (MiP) has been associated with adverse pregnancy outcomes. There is limited information on MiP in low transmission regions as Colombia. This study aimed to describe the epidemiology of MiP through active surveillance of infections by microscopy and polymerase chain reaction (PCR). Methods A cross-sectional study was conducted between May 2016 and January 2017 in five municipalities (Apartadó, Turbo, El Bagre, Quibdó, and Tumaco) in Colombia. Pregnant women self-presenting at health centers for antenatal care visits, seeking medical care for suspected malaria, or delivery, were enrolled. Diagnosis of Plasmodium spp was made in peripheral and placental blood samples by microscopy and PCR. Results A total of 787 pregnant women were enrolled; plasmodial infection was diagnosed by microscopy in 4.2% (95% CI 2.8-5.6; 33/787) or by nPCR in 5.3% (95% CI 3.8-6.9; 42/787) in peripheral blood. Most of the infections were caused by P. falciparum (78.5%), and 46% were afebrile (asymptomatic). Women in the first and second trimester of pregnancy were more likely to be infected (aOR = 3.06, 95%CI = 1.6 - 5.8). To live in the urban/peri-urban area (aOR = 3.04, 95%CI = 1.4 - 6.56), to have a history of malaria during last year (aOR = 5.45, 95%IC = 2.16 - 13.75), and the infrequent bed net usage (aOR = 2.8, 95%CI = 1.31 - 5.97) were associated with the infection. Pregnant infected women had a higher risk of anaemia (aOR = 2.18, 95%CI = 1.15 - 4.12) and fever (aOR = 14.2, 95%CI = 6.89 - 29.8). Conclusion The screening for malaria during antenatal care in endemic areas of Colombia is highly recommended due to the potential adverse effects of Plasmodium spp. infection in pregnancy and as an important activity for the surveillance of asymptomatic infections in the control of malaria.
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Howler monkeys are the reservoir of malarial parasites causing zoonotic infections in the Atlantic forest of Rio de Janeiro. PLoS Negl Trop Dis 2019; 13:e0007906. [PMID: 31815937 PMCID: PMC6922453 DOI: 10.1371/journal.pntd.0007906] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 12/19/2019] [Accepted: 11/05/2019] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Although malaria cases have substantially decreased in Southeast Brazil, a significant increase in the number of Plasmodium vivax-like autochthonous human cases has been reported in remote areas of the Atlantic Forest in the past few decades in Rio de Janeiro (RJ) state, including an outbreak during 2015-2016. The singular clinical and epidemiological aspects in several human cases, and collectively with molecular and genetic data, revealed that they were due to the non-human primate (NHP) parasite Plasmodium simium; however, the understanding of the autochthonous malarial epidemiology in Southeast Brazil can only be acquired by assessing the circulation of NHP Plasmodium in the foci and determining its hosts. METHODOLOGY A large sampling effort was carried out in the Atlantic forest of RJ and its bordering states (Minas Gerais, São Paulo, Espírito Santo) for collecting and examining free-living NHPs. Blood and/or viscera were analyzed for Plasmodium infections via molecular and microscopic techniques. PRINCIPAL FINDINGS In total, 146 NHPs of six species, from 30 counties in four states, were tested, of which majority were collected from RJ. Howler monkeys (Alouatta clamitans) were the only species found infected. In RJ, 26% of these monkeys tested positive, of which 17% were found to be infected with P. simium. Importantly, specific single nucleotide polymorphisms-the only available genetic markers that differentiate P. simium from P. vivax-were detected in all P. simium infected A. clamitans despite their geographical origin of malarial foci. Interestingly, 71% of P. simium infected NHPs were from the coastal slope of a mountain chain (Serra do Mar), where majority of the human cases were found. Plasmodium brasilianum/malariae was initially detected in 14% and 25% free-living howler monkeys in RJ and in the Espírito Santo (ES) state, respectively. Moreover, the malarial pigment was detected in the spleen fragments of 50% of a subsample comprising dead howler monkeys in both RJ and ES. All NHPs were negative for Plasmodium falciparum. CONCLUSIONS/SIGNIFICANCE Our data indicate that howler monkeys act as the main reservoir for the Atlantic forest human malarial parasites in RJ and other sites in Southeast Brazil and reinforce its zoonotic characteristics.
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Figueiredo MAP, Di Santi SM, Manrique WG, André MR, Machado RZ. Serological and molecular techniques applied for identification of Plasmodium spp. in blood samples from nonhuman primates. ACTA ACUST UNITED AC 2018; 27:363-376. [PMID: 30066720 DOI: 10.1590/s1984-296120180043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Accepted: 05/10/2018] [Indexed: 11/22/2022]
Abstract
The aim of this study was to identify Plasmodium spp. in blood samples from nonhuman primates (NHPs) in the state of Maranhão, using classical and alternative techniques for examination of human malaria. A total of 161 blood samples from NHPs were analyzed: 141 from captive animals at a Wildlife Screening Center (CETAS) and 20 from free-living animals in a private reserve. The techniques used were microscopy, rapid diagnostic test (RDT), Indirect fluorescent antibody test (IFAT) and molecular techniques (semi-nested PCR, quantitative real-time PCR and LAMP). Two serological methods (dot-ELISA and indirect ELISA) were also standardized with rhoptry protein-soluble antigen of P. falciparum and P. berghei. Trophozoite forms of Plasmodium sp. were identified on slides from five different animals. No samples were positive through RDT and LAMP. Four samples were seropositive for P. malariae through IFAT. The samples showed low reactivity to ELISA. Plasmodium sp. was detected in 34.16% (55/161) of the samples using qPCR based on the 18S rRNA gene. After sequencing, two samples showed 100% identityl to P. malariae, one showed 97% identity to Plasmodium sp. ZOOBH and one showed 99% identity to P. falciparum . PCR was shown to be the most sensitive technique for diagnosing Plasmodium in NHP samples.
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Affiliation(s)
- Mayra Araguaia Pereira Figueiredo
- Laboratório de Parasitologia Animal, Curso de Medicina Veterinária, Universidade Federal de Rondônia - UNIR, Rolim de Moura, RO, Brasil
| | - Silvia Maria Di Santi
- Centro de Estudos da Malária, Superintendência de Controle de Endemias - SUCEN, São Paulo, SP, Brasil.,Departamento de Saúde do Estado de São Paulo, Instituto de Medicina Tropical de São Paulo - IMTSP, Universidade de São Paulo - USP, São Paulo, SP, Brasil
| | - Wilson Gómez Manrique
- Laboratório de Patologia Veterinária, Curso de Medicina Veterinária, Universidade Federal de Rondônia - UNIR, Rolim de Moura, RO, Brasil
| | - Marcos Rogério André
- Laboratório de Imunoparasitologia, Faculdade de Ciências Agrárias e Veterinárias - FCAV, Universidade Estadual Paulista - UNESP, Jaboticabal, SP, Brasil
| | - Rosangela Zacarias Machado
- Laboratório de Imunoparasitologia, Faculdade de Ciências Agrárias e Veterinárias - FCAV, Universidade Estadual Paulista - UNESP, Jaboticabal, SP, Brasil
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Lima GF, Arroyo Sanchez MC, Levi JE, Fujimori M, da Cruz Caramelo L, Sanchez AR, Ramos-Sanchez EM, Inoue J, de Jesus Costa-Nascimento M, Mendrone A, Di Santi SM. Asymptomatic infections in blood donors harbouring Plasmodium: an invisible risk detected by molecular and serological tools. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2018; 16:17-25. [PMID: 27893347 PMCID: PMC5770310 DOI: 10.2450/2016.0118-16] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 05/02/2016] [Accepted: 08/25/2016] [Indexed: 06/06/2023]
Abstract
BACKGROUND Transfusion-transmitted malaria due to asymptomatic Plasmodium infections is a challenge for blood banks. There is a lack of data on the prevalence of asymptomatic infected blood donors and the incidence of transfusion-transmitted malaria in low endemicity areas worldwide. We estimated the frequency of blood donors harbouring Plasmodium in an area in which asymptomatic infections have been reported. MATERIAL AND METHODS To estimate the frequency of blood donors harbouring Plasmodium we used microscopy and molecular tools. Serological tests were applied to measure the exposure of candidates to Plasmodium antigens. Venous blood was collected from 91 candidates attending the "Pró-Sangue" Blood Centre Foundation in São Paulo, who lived in the municipality of Juquitiba, São Paulo, Brazil, where sporadic autochthonous cases of malaria have been described. Blood samples were used for parasitological, molecular and serological studies. RESULTS Among the 91 samples examined, rare Plasmodium forms were observed in two donors. Genus real-time polymerase chain reaction analysis demonstrated Plasmodium amplification in three candidates and species-specific nested polymerase chain reaction identified P. malariae in two. ELISA-IgG was reactive in 42.9% of samples for P. vivax (Pv-MSP119) and in 6.6% for P. falciparum (Pf-Zw). ELISA-IgM was reactive in 2.2% of samples for P. vivax and in 4.4% for P. falciparum. An indirect immunofluorescence assay was reactive for P. malariae in 15.4% of cases. DISCUSSION Reservoirs of Plasmodium represent a challenge for blood banks, since studies have shown that high levels of submicroscopic infections can occur in low transmission areas. The risk of transfusion-transmitted malaria presented here points to the need to conduct molecular investigations of candidate donors with any positive malarial antibody test.
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Affiliation(s)
| | | | - José E. Levi
- ”Pró-Sangue” Blood Centre Foundation, São Paulo, Brazil
| | - Mahyumi Fujimori
- Institute of Tropical Medicine, University of São Paulo, São Paulo, Brazil
| | | | | | | | - Juliana Inoue
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
| | | | | | - Silvia M. Di Santi
- Faculty of Medicine, University of São Paulo, São Paulo, Brazil
- Epidemic Disease Control Unit, São Paulo, Brazil
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Figueiredo MAP, Di Santi SM, Manrique WG, André MR, Machado RZ. Identification of Plasmodium spp. in Neotropical primates of Maranhense Amazon in Northeast Brazil. PLoS One 2017; 12:e0182905. [PMID: 28796820 PMCID: PMC5552124 DOI: 10.1371/journal.pone.0182905] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2017] [Accepted: 07/26/2017] [Indexed: 12/21/2022] Open
Abstract
In the Brazilian Amazon region, malaria caused by Plasmodium malariae is considered to be a zoonosis because of cross-transfer of the parasite between humans and Neotropical primates. To contribute information on this issue, we investigated occurrences of natural infection with Plasmodium sp. among Neotropical primates in the Maranhense Amazon (Amazon region of the state of Maranhão), in the northeastern region of Brazil. Blood samples were collected from 161 Neotropical primates of six species that were caught in an environmental reserve (Sítio Aguahy) and from captive primates (CETAS-Wildlife Screening Center, municipality of São Luís), in Maranhão. Plasmodium sp. was diagnosed based on light microscopy, PCR, qPCR and LAMP for amplification of the 18S rRNA gene. Serum samples were also assayed by means of indirect immunofluorescence for IgG antibodies against P. malariae/P. brasilianum, P. falciparum and P. berghei. Parasites were detected through light microscopy on five slides from captive primates (four Sapajus spp. and one Callithrix jacchus). In the molecular tests, 34.16% (55/161) and 29.81% (48/161) of the animals sampled were positive in the qPCR and PCR assays, respectively. In the PCR, 47/48 animals were positive for P. malariae/P. brasilianum; of these, eight were free-living primates and 39 from CETAS, São Luís. One sample showed a band in the genus-specific reaction, but not in the second PCR reaction. Anti-P. malariae/P. brasilianum IgG antibodies were detected in four serum samples from Sapajus spp. in captivity. In this study, circulation of P. malariae/P. brasilianum in Neotropical primates was confirmed, with low levels of parasitemia and low levels of antibodies. The importance of these animals as reservoirs of human malaria in the region studied is still unknown. This scenario has an impact on control and elimination of malaria in this region.
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Affiliation(s)
- Mayra Araguaia Pereira Figueiredo
- Laboratory of Immunoparasitology, School of Agrarian and Veterinary Sciences (FCAV), UNESP, Jaboticabal Campus, Jaboticabal, São Paulo, Brazil
| | - Silvia Maria Di Santi
- Center for Malaria Studies, Superintendency for Endemic Disease Control (SUCEN), Department of Health of the State of São Paulo/ Institute of Tropical Medicine of Sao Paulo (IMTSP), USP, Sao Paulo, São Paulo, Brazil
| | - Wilson Gómez Manrique
- Laboratory of Veterinary Pathology, Brazil University, Descalvado Campus, Descalvado, São Paulo, Brazil
| | - Marcos Rogério André
- Laboratory of Immunoparasitology, School of Agrarian and Veterinary Sciences (FCAV), UNESP, Jaboticabal Campus, Jaboticabal, São Paulo, Brazil
| | - Rosangela Zacarias Machado
- Laboratory of Immunoparasitology, School of Agrarian and Veterinary Sciences (FCAV), UNESP, Jaboticabal Campus, Jaboticabal, São Paulo, Brazil
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Carmona-Fonseca J, Agudelo OM, Arango EM. Asymptomatic plasmodial infection in Colombian pregnant women. Acta Trop 2017; 172:97-101. [PMID: 28460834 DOI: 10.1016/j.actatropica.2017.04.030] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2016] [Revised: 04/06/2017] [Accepted: 04/27/2017] [Indexed: 11/15/2022]
Abstract
Information about asymptomatic plasmodial infection is scarce in the world, and the current antimalarial program goals (control, elimination, and eradication) demand this evidence to be well documented in different populations and malaria transmission settings. This study aimed to measure the prevalence of API in Colombian pregnant women at delivery. A retrospective prevalence survey was used. Women were recruited at hospital obstetric facility in each of the municipalities of Turbo, Necoclí in Antioquia department, and Puerto Libertador in Córdoba department. Malaria infection was tested by thick blood smear (TBS) and real-time quantitative PCR (qPCR). Ninety-six pregnant women at delivery were studied: 95% were asymptomatic (91/96), 45% had asymptomatic plasmodial infection (API) by qPCR (41/91), and only 8% (7/91) had API by microscopy. The prevalence of submicroscopic infections (TBS negative and qPCR positive) was very high, 37% (34/91) in asymptomatic women and 41% (39/96) in total women studied (91 asymptomatic and 5 symptomatic). The prevalence of API in Colombian pregnant women is much higher than which is expected for a country that does not have the level of malaria transmission as Sub-Saharan African countries.
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Affiliation(s)
| | - Olga M Agudelo
- Grupo Salud y Comunidad-César Uribe Piedrahíta, Universidad de Antioquia, Colombia
| | - Eliana M Arango
- Grupo Salud y Comunidad-César Uribe Piedrahíta, Universidad de Antioquia, Colombia.
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Recht J, Siqueira AM, Monteiro WM, Herrera SM, Herrera S, Lacerda MVG. Malaria in Brazil, Colombia, Peru and Venezuela: current challenges in malaria control and elimination. Malar J 2017; 16:273. [PMID: 28676055 PMCID: PMC5496604 DOI: 10.1186/s12936-017-1925-6] [Citation(s) in RCA: 134] [Impact Index Per Article: 19.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Accepted: 06/29/2017] [Indexed: 01/24/2023] Open
Abstract
In spite of significant progress towards malaria control and elimination achieved in South America in the 2000s, this mosquito-transmitted tropical disease remains an important public health concern in the region. Most malaria cases in South America come from Amazon rain forest areas in northern countries, where more than half of malaria is caused by Plasmodium vivax, while Plasmodium falciparum malaria incidence has decreased in recent years. This review discusses current malaria data, policies and challenges in four South American Amazon countries: Brazil, Colombia, Peru and the Bolivarian Republic of Venezuela. Challenges to continuing efforts to further decrease malaria incidence in this region include: a significant increase in malaria cases in recent years in Venezuela, evidence of submicroscopic and asymptomatic infections, peri-urban malaria, gold mining-related malaria, malaria in pregnancy, glucose-6-phosphate dehydrogenase (G6PD) deficiency and primaquine use, and possible under-detection of Plasmodium malariae. Some of these challenges underscore the need to implement appropriate tools and procedures in specific regions, such as a field-compatible molecular malaria test, a P. malariae-specific test, malaria diagnosis and appropriate treatment as part of regular antenatal care visits, G6PD test before primaquine administration for P. vivax cases (with weekly primaquine regimen for G6PD deficient individuals), single low dose of primaquine for P. falciparum malaria in Colombia, and national and regional efforts to contain malaria spread in Venezuela urgently needed especially in mining areas. Joint efforts and commitment towards malaria control and elimination should be strategized based on examples of successful regional malaria fighting initiatives, such as PAMAFRO and RAVREDA/AMI.
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Affiliation(s)
| | - André M Siqueira
- Instituto Nacional de Infectologia Evandro Chagas, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Wuelton M Monteiro
- Diretoria de Ensino e Pesquisa, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil
| | - Sonia M Herrera
- Centro de Investigación Científica Caucaseco, Cali, Colombia
| | | | - Marcus V G Lacerda
- Diretoria de Ensino e Pesquisa, Fundação de Medicina Tropical Dr. Heitor Vieira Dourado, Manaus, Amazonas, Brazil.,Fiocruz/Fundação de Medicina Tropical Dr. Heitor Vieira Dourado/Institute Elimina, Manaus, Brazil
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Lima GFMDC, Lucchi NW, Silva-Flannery L, Macedo- de- Oliveira A, Hristov AD, Inoue J, Costa-Nascimento MDJ, Udhayakumar V, Di Santi SM. Still Searching for a Suitable Molecular Test to Detect Hidden Plasmodium Infection: A Proposal for Blood Donor Screening in Brazil. PLoS One 2016; 11:e0150391. [PMID: 26959994 PMCID: PMC4784969 DOI: 10.1371/journal.pone.0150391] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2015] [Accepted: 02/12/2016] [Indexed: 11/18/2022] Open
Abstract
Background Efforts have been made to establish sensitive diagnostic tools for malaria screening in blood banks in order to detect malaria asymptomatic carriers. Microscopy, the malaria reference test in Brazil, is time consuming and its sensitivity depends on microscopist experience. Although molecular tools are available, some aspects need to be considered for large-scale screening: accuracy and robustness for detecting low parasitemia, affordability for application to large number of samples and flexibility to perform on individual or pooled samples. Methodology In this retrospective study, we evaluated four molecular assays for detection of malaria parasites in a set of 56 samples previously evaluated by expert microscopy. In addition, we evaluated the effect of pooling samples on the sensitivity and specificity of the molecular assays. A well-characterized cultured sample with 1 parasite/μL was included in all the tests evaluated. DNA was extracted with QIAamp DNA Blood Mini Kit and eluted in 50 μL to concentrate the DNA. Pools were assembled with 10 samples each. Molecular protocols targeting 18S rRNA, included one qPCR genus specific (Lima-genus), one duplex qPCR genus/Pf (PET-genus, PET-Pf) and one duplex qPCR specie-specific (Rougemont: Roug-Pf/Pv and Roug-Pm/Po). Additionally a nested PCR protocol specie-specific was used (Snou-Pf, Snou-Pv, Snou-Pm and Snou-Po). Results The limit of detection was 3.5 p/μL and 0.35p/μl for the PET-genus and Lima-genus assays, respectively. Considering the positive (n = 13) and negative (n = 39) unpooled individual samples according to microscopy, the sensitivity of the two genus qPCR assays was 76.9% (Lima-genus) and 72.7% (PET-genus). The Lima-genus and PET-genus showed both sensitivity of 86.7% in the pooled samples. The genus protocols yielded similar results (Kappa value of 1.000) in both individual and pooled samples. Conclusions Efforts should be made to improve performance of molecular tests to enable the detection of low-density parasitemia if these tests are to be utilized for blood transfusion screening.
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Affiliation(s)
| | - Naomi W. Lucchi
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Luciana Silva-Flannery
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
- Atlanta Research and Education Foundation, Decatur-GA, Atlanta, Georgia, United States of America
| | - Alexandre Macedo- de- Oliveira
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Angelica D Hristov
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Juliana Inoue
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Maria de Jesus Costa-Nascimento
- Núcleo de Estudos em Malária, Superintendência de Controle de Endemias, Secretaria de Estado da Saúde de São Paulo /Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, São Paulo, SP, Brasil
| | - Venkatachalam Udhayakumar
- Malaria Branch, Division of Parasitic Diseases and Malaria, Centers for Disease Control and Prevention, Atlanta, Georgia, United States of America
| | - Silvia M Di Santi
- Departamento de Moléstias Infecciosas e Parasitárias, Faculdade de Medicina, Universidade de São Paulo, São Paulo, SP, Brasil
- Núcleo de Estudos em Malária, Superintendência de Controle de Endemias, Secretaria de Estado da Saúde de São Paulo /Instituto de Medicina Tropical de São Paulo, Universidade de São Paulo, São Paulo, SP, Brasil
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Yanow SK, Gavina K, Gnidehou S, Maestre A. Impact of Malaria in Pregnancy as Latin America Approaches Elimination. Trends Parasitol 2016; 32:416-427. [PMID: 26875608 DOI: 10.1016/j.pt.2016.01.008] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Revised: 01/14/2016] [Accepted: 01/19/2016] [Indexed: 11/29/2022]
Abstract
In Latin America, four million pregnancies are at risk of malaria annually, but malaria in pregnancy is largely overlooked. As countries progress toward malaria elimination, targeting reservoirs of transmission is a priority. Pregnant women are an important risk group because they harbor asymptomatic infections and dormant liver stages of Plasmodium vivax that cause relapses. Of significant concern is the discovery that most infections in pregnant women fail to be detected by routine diagnostics. We review here recent findings on malaria in pregnancy within Latin America. We focus on the Amazon basin and Northwest Colombia, areas that harbor the greatest burden of malaria, and propose that more sensitive diagnostics and active surveillance at antenatal clinics will be necessary to eliminate malaria from these final frontiers.
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Affiliation(s)
- Stephanie K Yanow
- School of Public Health, University of Alberta, Edmonton, Alberta, Canada; Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada.
| | - Kenneth Gavina
- Department of Medical Microbiology and Immunology, University of Alberta, Edmonton, Alberta, Canada
| | - Sedami Gnidehou
- Department of Biology, Campus Saint-Jean, University of Alberta, Edmonton, Alberta, Canada
| | - Amanda Maestre
- Grupo Salud y Comunidad, Universidad de Antioquia, Medellín, Colombia
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