Publications by authors named "Ratsimbasoa A"

Introduction: This paper presents (a) the progress made towards achieving the 2023 Lymphatic Filariasis (LF) Mass Drug Administration (MDA) campaign goals, (b) the estimated financial savings resulting from integrating LF MDA into Polio immunization campaigns, and (c) the best practices, challenges, and recommendations.

Methods: In 2023, 21,336,057 people in 83 districts were affected by LF and required Preventive Chemotherapy (PC). The National NTD Control Programme (NTDCP) conducted three phases of LF MDA campaigns in those districts.

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Malaria remains a significant public health concern in Madagascar. The WHO recommends using parasitological methods to confirm Plasmodium infection before treatment. This study evaluated the performance of two rapid diagnostic tests (RDTs), Bioline™ Malaria Ag Pf/Pan (Abbott Point of Care, Princeton, NJ) and Bioline™ Malaria Ag Pf/Pv (Abbott Point of Care, Princeton, NJ), compared with microscopy and polymerase chain reaction (PCR) as reference methods.

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Background: Despite the high prevalence of mental disorders and epilepsy in low- and middle-income countries, nearly 80% of patients are not treated. In Madagascar, initiatives to improve access to epilepsy and mental health care, including public awareness and training of general practitioners (GPs), were carried out between 2013 and 2018. Our study's main objective was to assess the effectiveness of these initiatives, two to five years post-intervention.

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Article Synopsis
  • Vivax malaria was previously thought to be absent in sub-Saharan Africa because many people lack the Duffy antigen receptor (DARC), which is key for the malaria parasite P. vivax to invade red blood cells.
  • New research has found that some Duffy-negative individuals can temporarily express DARC during the development of their red blood cells, allowing P. vivax to invade these cells.
  • This indicates that there may be many Duffy-negative individuals silently harboring P. vivax infections, potentially leading to underreported health issues in the region.
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The erythrocyte silent Duffy blood group phenotype in Africans is thought to confer resistance to Plasmodium vivax blood-stage infection. However, recent studies report P. vivax infections across Africa in Fy-negative individuals.

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Background: The effectiveness of community delivery of intermittent preventive treatment (C-IPT) of malaria in pregnancy (IPTp) with sulfadoxine-pyrimethamine has been evaluated in selected areas of the Democratic Republic of the Congo, Madagascar, Mozambique, and Nigeria. We aimed to assess the effect of C-IPTp on the potential development of Plasmodium falciparum resistance to sulfadoxine-pyrimethamine, since it could threaten the effectiveness of this strategy.

Methods: Health facility-based cross-sectional surveys were conducted at baseline and 3 years after C-IPTp implementation in two neighbouring areas per country, one with C-IPTp intervention, and one without, in the four project countries.

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Antimalarial primaquine (PQ) eliminates liver hypnozoites of   gene variation contributes to PQ therapeutic failure. Additional gene variation may contribute to PQ efficacy. Information on pharmacogenomic variation in Madagascar, with malaria and a unique population admixture, is scanty.

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Background: Gametocytes are the sexual stages ensuring continuity of the development cycle of the parasite, as well as its transmission to humans. The efficacy of artemisinin-based anti-malarials against asexual stages of Plasmodium has been reported in Madagascar, but their effects on gametocytes are not well documented. The present study aims to determine the emergence of gametocyte and gametocyte clearance after artesunate-amodiaquine (ASAQ) or artemether-lumefantrine (AL) treatment in children with uncomplicated Plasmodium falciparum malaria in 5 regions of Madagascar.

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Background: Malaria is a parasitic disease caused by a hematozoan of the genus Early diagnosis followed by effective treatment is one of the keys to control this disease. In Madagascar, after more than 60 years of use for the treatment of uncomplicated malaria, chloroquine (CQ) was abandoned in favor of artesunate + amodiaquine (ASAQ) combination because of high prevalence of CQ treatment failure. Surveillance based on the assessment of therapeutic efficacy and genetic markers of resistance to antimalarials is therefore essential in order to detect the emergence of potentially resistant parasites as early as possible.

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Background: Rapid diagnostic tests (RDT) are widely used for malaria diagnosis in Madagascar, where Plasmodium falciparum is the predominant species. Molecular diagnosis is essential for malaria surveillance, but requires additional blood samples for DNA extraction. Used RDTs is an attractive alternative that can be used as a source of DNA.

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malaria is endemic in Madagascar, where populations have genetic inheritance from Southeast Asia and East Africa. Primaquine, a drug of choice for vivax malaria, is metabolized principally via CYP2D6. variation was characterized by locus-specific gene sequencing and was compared with TaqMan™ genotype data.

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Histidine-rich protein 2 (HRP2)-based rapid diagnostic tests detect Plasmodium falciparum malaria and are used throughout sub-Saharan Africa. However, deletions in the pfhrp2 and related pfhrp3 (pfhrp2/3) genes threaten use of these tests. Therapeutic efficacy studies (TESs) enroll persons with symptomatic P.

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Introduction: Epilepsy is a chronic disease of the brain that affects approximately 50 million people globally, with over 80 % of them living in low- and middle-income countries (LMICs). In Madagascar, as in most LMICs, one of the main obstacles to treatment is the stigma and discrimination experienced by patients. Beliefs and prejudices regarding this disease are common, especially among children.

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Background: Assessment of the genetic diversity of Plasmodium falciparum parasites from various malaria transmission settings could help to define tailored local strategies for malaria control and elimination. Such assessments are currently scarce in Madagascar. The study presented here aimed to bridge this gap by investigating the genetic diversity of P.

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is one of the five human malaria parasite species, which has a wide geographical distribution and can cause severe disease and fatal outcomes. It has the ability to relapse from dormant liver stages (hypnozoites), weeks to months after clearance of the acute blood-stage infection. An 8-aminoquinoline drug primaquine (PQ) can clear the hypnozoites, and thus can be used as an anti-relapse therapeutic agent.

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Malaria transmission in Madagascar is highly heterogeneous, exhibiting spatial, seasonal and long-term trends. Previous efforts to map malaria risk in Madagascar used prevalence data from Malaria Indicator Surveys. These cross-sectional surveys, conducted during the high transmission season most recently in 2013 and 2016, provide nationally representative prevalence data but cover relatively short time frames.

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Background: In low-malaria-transmission areas of Madagascar, annual parasite incidence (API) from routine data has been used to target indoor residual spraying at subdistrict commune level. To assess validity of this approach, we conducted school-based serological surveys and health facility (HF) data quality assessments in 7 districts to compare API to gold-standard commune-level serological measures.

Methods: At 2 primary schools in each of 93 communes, 60 students were randomly selected with parents and teachers.

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Background: The Madagascar National Strategic Plan for Malaria Control 2018 (NSP) outlines malaria control pre-elimination strategies that include detailed goals for mosquito control. Primary surveillance protocols and mosquito control interventions focus on indoor vectors of malaria, while many potential vectors feed and rest outdoors. Here we describe the application of tools that advance our understanding of diversity, host choice, and Plasmodium infection in the Anopheline mosquitoes of the Western Highland Fringe of Madagascar.

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Introduction: This study aims to assess the adherence of private health providers to the use of malaria rapid diagnostic tests (RDTs) and to the prescription of artemisinin-containing combinations (ACT) in patients with uncomplicated malaria.

Methods: We conducted an analytical, retrospective and cross-sectional study in 11 Madagascar's health districts divided into four epidemiological strata in September and in October 2015. A total of 43 health providers from 39 private health care facilities (PHF) were interviewed and visited.

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Current malaria rapid diagnostic tests (RDTs) contain antibodies against -specific histidine-rich protein 2 (PfHRP2), lactate dehydrogenase (pLDH), and aldolase in various combinations. Low or high parasite densities/target antigen concentrations may influence the accuracy and sensitivity of PfHRP2-detecting RDTs. We analyzed the SD Bioline Malaria Ag P.

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mosquitoes vary in habitat preference, feeding pattern, and susceptibility to various measures of vector control. Consequently, it is important that we identify reservoirs of disease, identify vectors, and characterize feeding patterns to effectively implement targeted control measures. Using 467 anopheline mosquito abdomen squashes captured in Madagascar, we designed a novel ligase detection reaction and fluorescent microsphere assay, dubbed Bloodmeal Detection Assay for Regional Transmission (BLOODART), to query the bloodmeal content, identify five mosquito species, and detect infection.

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Community prevalence of infection is a widely used, standardized metric for evaluating malaria endemicity. Conventional methods for measuring prevalence include light microscopy and rapid diagnostic tests (RDTs), but their detection thresholds are inadequate for diagnosing low-density infections. The significance of submicroscopic malaria infections is poorly understood in Madagascar, a country of heterogeneous malaria epidemiology.

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Background: Since 2006, the artemisinin-based combination therapy (ACT) are recommended to treat uncomplicated malaria including non Plasmodium falciparum malaria in Madagascar. Artesunate-amodiaquine (ASAQ) and artemether-lumefantrine are the first- and second-line treatment in uncomplicated falciparum malaria, respectively. No clinical drug efficacy study has been published since 2009 to assess the efficacy of these two artemisinin-based combinations in Madagascar, although the incidence of malaria cases has increased from 2010 to 2016.

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Background: Reliable measures of disease burden over time are necessary to evaluate the impact of interventions and assess sub-national trends in the distribution of infection. Three Malaria Indicator Surveys (MISs) have been conducted in Madagascar since 2011. They provide a valuable resource to assess changes in burden that is complementary to the country's routine case reporting system.

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histidine-rich protein 2 (PfHRP2) forms the basis of many current malaria rapid diagnostic tests (RDTs). However, the parasites lacking part or all of the gene do not express the PfHRP2 protein and are, therefore, not identifiable by PfHRP2-detecting RDTs. We evaluated the performance of the SD Bioline Malaria Ag P.

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