Publications by authors named "Milijaona Randrianarivelojosia"

Article Synopsis
  • * This study analyzed the costs and effectiveness of two malaria control interventions—Insecticide-Treated Nets (ITNs) and Indoor Residual Spraying (IRS)—in two districts, comparing their cost-effectiveness ratios (CERs) to determine the better intervention.
  • * From 2009 to 2013, the National Malaria Control Program (NMCP) cost approximately USD 45.4 million annually, with IRS being significantly more expensive than ITNs; the CER for IRS was about six times higher than that of ITNs, indicating that ITNs might be
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Malaria is a major public health problem in Madagascar, particularly in coastal areas. We conducted a randomized, controlled, parallel-group study of artemisinin-based combination therapy (ACT) in Mananjary and Farafangana, two localities on the rainy south-east coast of Madagascar, from March to September 2018. The efficacy and safety of artesunate + amodiaquine (ASAQ) and artemether + lumefantrine (AL) were assessed according to the WHO protocol with a 28-day follow-up.

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We describe the MalariaGEN Pf7 data resource, the seventh release of genome variation data from the MalariaGEN network.  It comprises over 20,000 samples from 82 partner studies in 33 countries, including several malaria endemic regions that were previously underrepresented.  For the first time we include dried blood spot samples that were sequenced after selective whole genome amplification, necessitating new methods to genotype copy number variations.

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Background: Malaria remains a leading cause of morbidity and mortality worldwide, with progress in malaria control stalling in recent years. Proactive community case management (pro-CCM) has been shown to increase access to diagnosis and treatment and reduce malaria burden. However, lack of experimental evidence may hinder the wider adoption of this intervention.

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Background: Targeted research on residual malaria transmission is important to improve strategies in settings pursuing elimination, where transmission reductions prove challenging. This study aimed to detect and characterize spatial heterogeneity and factors associated with Plasmodium falciparum infections and exposure, P. falciparum apical membrane antigen 1 (PfAMA1) antibody (Ab) response, in the Central Highlands of Madagascar (CHL).

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This report describes the MalariaGEN Pv4 dataset, a new release of curated genome variation data on 1,895 samples of collected at 88 worldwide locations between 2001 and 2017. It includes 1,370 new samples contributed by MalariaGEN and VivaxGEN partner studies in addition to previously published samples from these and other sources. We provide genotype calls at over 4.

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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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Interactions between the prokaryotic microbiome and eukaryotic parasites in the vertebrate gut may affect overall host health and disease. While intertropical areas exhibit a high rate of parasites carriers, such interactions are understudied in these populations. Our objectives were to (1) describe the gut microbiome of individuals living in Madagascar, (2) identify potential associations between bacterial taxa and parasites colonizing the digestive tract and (3) highlight main determinants of the gut microbiota composition in this developing country.

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Article Synopsis
  • MalariaGEN is a global data-sharing network focused on studying the genomic epidemiology of malaria, releasing new genome variation data from 7,000 samples across 28 malaria-endemic countries.
  • The project generated high-quality genotype data on 3 million single nucleotide polymorphisms (SNPs) and identified drug resistance factors, revealing that nearly all samples showed some genetic resistance to antimalarial drugs.
  • The ongoing expansion of this open data resource aims to enhance research on malaria's evolution and improve tools necessary for malaria surveillance and elimination efforts.
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Article Synopsis
  • The study focuses on the apicomplexan parasites, particularly the genus Plasmodium, with an emphasis on their impact on public health, highlighting the need for more information on bat blood parasites in Madagascar.
  • Recent findings show specific associations between the genus Polychromophilus and certain bat families, revealing marked host specificity in infections.
  • The research involved fieldwork and molecular techniques to identify these parasites in eastern Madagascar, with 222 bats analyzed, leading to the discovery of a monophyletic group of Polychromophilus species with distinct clades.
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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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Targeted Next Generation Sequencing (TNGS) is an efficient and economical Next Generation Sequencing (NGS) platform and the preferred choice when specific genomic regions are of interest. So far, only institutions located in middle and high-income countries have developed and implemented the technology, however, the efficiency and cost savings, as opposed to more traditional sequencing methodologies (e.g.

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Understanding genomic variation and population structure of across Africa is necessary to sustain progress toward malaria elimination. Genome clustering of 2263 isolates from 24 malaria-endemic settings in 15 African countries identified major western, central, and eastern ancestries, plus a highly divergent Ethiopian population. Ancestry aligned to these regional blocs, overlapping with both the parasite's origin and with historical human migration.

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On the island of Madagascar, prior to the arrival of the Europeans, some pathologies including malaria, locally known as tazo (fever), were already described. As part of the Malagasy traditional knowledge, traditional medicine mainly based on the use of herbal remedies is part of the malaria treatment still today. Across the country, hundreds of plants are identified as antimalarial, and some compounds from plants show interesting in vitro activities against human Plasmodium.

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Introduction: In Madagascar, malaria control relies on the countrywide use of long lasting insecticide treated bed nets (LLINs) and on indoor residual spraying (IRS) in the central highland area as well as a small area on the eastern coast. We tested insecticide resistance mechanisms of from Tsararano, a malaria endemic village in the coastal health district of Marovoay.

Methods: Insecticide susceptibility bioassays were done in July 2017 on first-generation (F1) to assess (i) the susceptibility to permethrin (0.

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Introduction: Intestinal parasitic infections are a major public health problem in inter-tropical areas. The aim of our study was to describe the situation in Mahajanga, Madagascar with a particular focus on two protozoa, Dientamoeba fragilis and Blastocystis sp.

Methods: This was a prospective study from February to June 2015.

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Background: The reduction of global malaria burden over the past 15 years is much attributed to the expansion of mass distribution campaigns (MDCs) of long-lasting insecticidal nets (LLIN). In Madagascar, two LUN MDCs were implemented and one district also benefited from a community-based continuous distribution (CB-CD). Malaria incidence dropped but eventually rebounded after a decade.

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Background: Bats are home to diverse haemosporidian parasites namely Plasmodium and Plasmodium-related. While information is available at a worldwide level, haemosporidian infection in bats from Madagascar is still scarce and recent changes in the taxonomy of the island's bat fauna, particularly the description of several new species, require a reassessment of previously described patterns, including blood parasite ecology and vectorial transmission.

Methods: A sample representing seven of the nine known bat families and 31 of the 46 currently recognized taxa from Madagascar and collected in the western and central portions of the island were screened by PCR for the presence of Polychromophilus.

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Background: The increasing use of malaria diagnostic tests reveals a growing proportion of patients with fever but no malaria. Clinicians and health care workers in low-income countries have few tests to diagnose causes of fever other than malaria although several diseases share common symptoms. We propose here to assess etiologies of fever in Madagascar to ultimately improve management of febrile cases.

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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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: Thanks to a considerable increase in funding, malaria control interventions (MCI) whose efficacy had been demonstrated by controlled trials have been largely scaled up during the last decade. Nevertheless, it was not systematically investigated whether this efficacy had been preserved once deployed on the field. Therefore, we sought the literature to assess the disparities between efficacy and effectiveness and the effort to measure the protective effectiveness (PE) of MCI.

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Background: The use of a malaria early warning system (MEWS) to trigger prompt public health interventions is a key step in adding value to the epidemiological data routinely collected by sentinel surveillance systems.

Methods: This study describes a system using various epidemic thresholds and a forecasting component with the support of new technologies to improve the performance of a sentinel MEWS. Malaria-related data from 21 sentinel sites collected by Short Message Service are automatically analysed to detect malaria trends and malaria outbreak alerts with automated feedback reports.

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The widespread distribution and relapsing nature of Plasmodium vivax infection present major challenges for the elimination of malaria. To characterize the genetic diversity of this parasite in individual infections and across the population, we performed deep genome sequencing of >200 clinical samples collected across the Asia-Pacific region and analyzed data on >300,000 SNPs and nine regions of the genome with large copy number variations. Individual infections showed complex patterns of genetic structure, with variation not only in the number of dominant clones but also in their level of relatedness and inbreeding.

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Background: Recent gains in reducing the global burden of malaria are threatened by the emergence of Plasmodium falciparum resistance to artemisinins. The discovery that mutations in portions of a P. falciparum gene encoding kelch (K13)-propeller domains are the major determinant of resistance has provided opportunities for monitoring such resistance on a global scale.

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Background: Because international funding for malaria control is plateauing, affected countries that receive foreign funding are expected to maintain a constant budget while continuing to reduce Plasmodium transmission. To investigate the appropriateness of a malaria control policy in Madagascar, the effectiveness of all currently deployed malaria control interventions (MCIs) was measured.

Methods: A nationwide cross-sectional survey was conducted in 2012-2013 at 62 sites throughout Madagascar.

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