Publications by authors named "Daniel Neafsey"

We present a genome assembly from an individual female (the malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae) from Lopé, Gabon. The genome sequence is 225.7 megabases in span.

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We present genome assembly from individual female (African malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae) from Lopé, Gabon. The genome sequence is 270 megabases in span. Most of the assembly is scaffolded into three chromosomal pseudomolecules with the X sex chromosome assembled for both species.

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The malaria parasites Plasmodium falciparum and Plasmodium vivax differ in key biological processes and associated clinical effects, but consequences on population-level transmission dynamics are difficult to predict. This co-endemic malaria study from Guyana details important epidemiological contrasts between the species by coupling population genomics (1396 spatiotemporally matched parasite genomes, primarily from 2020-21) with sociodemographic analysis (nationwide patient census from 2019). We describe how P.

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Persistence of malaria parasites in asymptomatic hosts is crucial in areas of seasonally-interrupted transmission, where P. falciparum bridges wet seasons months apart. During the dry season, infected erythrocytes exhibit extended circulation with reduced cytoadherence, increasing the risk of splenic clearance of infected cells and hindering parasitaemia increase.

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Antimalarial resistance in is a public health problem in the fight against malaria in Ecuador. Characterizing the molecular epidemiology of drug resistance genes helps to understand the emergence and spread of resistant parasites. In this study, the effects of drug pressure and human migration on antimalarial resistance in were evaluated.

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Plasmodium parasites, the causal agents of malaria, are eukaryotic organisms that obligately undergo sexual recombination within mosquitoes. In low transmission settings, parasites recombine with themselves, and the clonal lineage is propagated rather than broken up by outcrossing. We investigated whether stochastic/neutral factors drive the persistence and abundance of Plasmodium falciparum clonal lineages in Guyana, a country with relatively low malaria transmission, but the only setting in the Americas in which an important artemisinin resistance mutation (pfk13 C580Y) has been observed.

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Unlabelled: Species distributed across heterogeneous environments often evolve locally adapted populations, but understanding how these persist in the presence of homogenizing gene flow remains puzzling. In Gabon, a major African malaria mosquito is found along an ecological gradient, including a sylvatic population, away of any human presence. This study identifies into the genomic signatures of local adaptation in populations from distinct environments including the urban area of Libreville, and two proximate sites 10km apart in the La Lopé National Park (LLP), a village and its sylvatic neighborhood.

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Article Synopsis
  • The RTS,S/AS01 malaria vaccine was tested for its effectiveness in a study involving 1,500 children aged 5-17 months in Ghana and Kenya, focusing on different dosing regimens.
  • Four different groups received the vaccine in varying full and fractional doses, while a control group got a rabies vaccine.
  • Results showed all RTS,S/AS01 regimens provided similar vaccine efficacy (25-43%) against new malaria infections, significantly reducing the number of infections over a 20-month follow-up period.
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Background: Subcutaneous administration of the monoclonal antibody L9LS protected adults against controlled infection in a phase 1 trial. Whether a monoclonal antibody administered subcutaneously can protect children from infection in a region where this organism is endemic is unclear.

Methods: We conducted a phase 2 trial in Mali to assess the safety and efficacy of subcutaneous administration of L9LS in children 6 to 10 years of age over a 6-month malaria season.

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parasites, the causal agents of malaria, are eukaryotic organisms that obligately undergo sexual recombination within mosquitoes. However, in low transmission settings where most mosquitoes become infected with only a single parasite clone, parasites recombine with themselves, and the clonal lineage is propagated rather than broken up by outcrossing. We investigated whether stochastic/neutral factors drive the persistence and abundance of clonal lineages in Guyana, a country with relatively low malaria transmission, but the only setting in the Americas in which an important artemisinin resistance mutation ( C580Y) has been observed.

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Since the discovery of natural malaria vector populations infected by the endosymbiont bacterium , a renewed interest has arisen for using this bacterium as an alternative for malaria control. Among naturally infected mosquitoes, , a major malaria mosquito in Central Africa, exhibits one of the highest prevalences of infection. To better understand whether this maternally inherited bacterium could be used for malaria control, we investigated influence in populations naturally infected by the malaria parasite .

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We present a genome assembly from an individual male (the malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae), from a wild population in Cameroon. The genome sequence is 271 megabases in span. The majority of the assembly is scaffolded into three chromosomal pseudomolecules with the X sex chromosome assembled.

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Background: The only licensed malaria vaccine, RTS,S/AS01 , confers moderate protection against symptomatic disease. Because many malaria infections are asymptomatic, we conducted a large-scale longitudinal parasite genotyping study of samples from a clinical trial exploring how vaccine dosing regimen affects vaccine efficacy (VE).

Methods: 1,500 children aged 5-17 months were randomized to receive four different RTS,S/AS01 regimens or a rabies control vaccine in a phase 2b clinical trial in Ghana and Kenya.

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Article Synopsis
  • Plasmodium falciparum, the deadly malaria-causing parasite, has shown resistance to dihydroartemisinin-piperaquine, a recommended treatment, first noted in Southeast Asia and suspected in South America.* -
  • A study in French Guiana found that 47% of tested P. falciparum cases were resistant to piperaquine, with specific genetic markers like pfCRT and pfpm2/pfpm3 amplifications strongly linked to this resistance.* -
  • The prevalence of these resistance markers varies regionally, with especially high rates in Suriname and Guyana, and shows a different pattern of genetic evolution compared to Southeast Asia, indicating unique geographical influences on resistance development.*
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We present a genome assembly from an individual female (the malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae), Ifakara strain. The genome sequence is 264 megabases in span. Most of the assembly is scaffolded into three chromosomal pseudomolecules with the X sex chromosome assembled.

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We present a genome assembly from an individual female (the malaria mosquito; Arthropoda; Insecta; Diptera; Culicidae). The genome sequence is 251 megabases in span. The majority of the assembly is scaffolded into three chromosomal pseudomolecules with the X sex chromosome assembled.

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The human malaria parasite Plasmodium falciparum is globally widespread, but its prevalence varies significantly between and even within countries. Most population genetic studies in P. falciparum focus on regions of high transmission where parasite populations are large and genetically diverse, such as sub-Saharan Africa.

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Successful infectious disease interventions can result in large reductions in parasite prevalence. Such demographic change has fitness implications for individual parasites and may shift the parasite's optimal life history strategy. Here, we explore whether declining infection rates can alter 's investment in sexual versus asexual growth.

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Multiplexed PCR amplicon sequencing (AmpSeq) is an increasingly popular application for cost-effective monitoring of threatened species and managed wildlife populations, and shows strong potential for the genomic epidemiology of infectious disease. AmpSeq data from infectious microbes can inform disease control in multiple ways, such as by measuring drug resistance marker prevalence, distinguishing imported from local cases, and determining the effectiveness of therapeutics. We describe the design and comparative evaluation of two new AmpSeq assays for Plasmodium falciparum malaria parasites: a four-locus panel ("4CAST") composed of highly diverse antigens, and a 129-locus panel ("AMPLseq") composed of drug resistance markers, highly diverse loci for inferring relatedness, and a locus to detect Plasmodium vivax co-infection.

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Potent and durable vaccine responses will be required for control of malaria caused by Plasmodium falciparum (Pf). RTS,S/AS01 is the first, and to date, the only vaccine that has demonstrated significant reduction of clinical and severe malaria in endemic cohorts in Phase 3 trials. Although the vaccine is protective, efficacy declines over time with kinetics paralleling the decline in antibody responses to the Pf circumsporozoite protein (PfCSP).

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Article Synopsis
  • - The RTS,S/AS01 vaccine showed moderate effectiveness against malaria in African infants and children, prompting researchers to investigate how the immune system responds to the vaccination.
  • - Using a unique blood transcriptional module framework, the study analyzed immune responses before and after vaccination, revealing significant changes in T-cell activation but fewer indications that these changes directly impacted malaria risk.
  • - The findings suggest that certain immune markers present before vaccination are linked to malaria risk, indicating potential roles for specific immune cell types in either promoting or inhibiting vaccine protection.
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Insecticide resistance is a major threat to gains in malaria control, which have been stalling and potentially reversing since 2015. Studies into the causal mechanisms of insecticide resistance are painting an increasingly complicated picture, underlining the need to design and implement targeted studies on this phenotype. In this study, we compare three populations of the major malaria vector An.

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Parasite and vector genetic data can guide malaria control, and technological advances are enabling more informative genetic data generation at unprecedented scales. Jacob et al. employ multiplexed amplicon sequencing to profile parasite genetic diversity from thousands of malaria samples, illuminating spatiotemporal patterns of drug resistance to inform regional drug policy change.

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Profiling of serological responses to establish the landscape of antibody specificities in individuals exposed to pathogens or vaccines is crucial for (a) revealing humoral immune correlates of protection; (b) uncovering markers of pathogen exposure; and (c) identifying antigens and epitopes associated with disease protection. Establishing the antigenic profile of serological responses requires either expensive microarrays or labor- and time-intensive ELISA assays. Multiplex assay platforms are increasingly being evaluated for their usefulness for high-throughput testing of sera or plasma.

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Background: The population history of Plasmodium simium, which causes malaria in sylvatic Neotropical monkeys and humans along the Atlantic Coast of Brazil, remains disputed. Genetically diverse P vivax populations from various sources, including the lineages that founded the species P simium, are thought to have arrived in the Americas in separate migratory waves.

Methods: We use population genomic approaches to investigate the origin and evolution of P simium.

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