Dataset Information

Plasmodium falciparum sexual conversion rates can be affected by artemisinin-based treatment in naturally infected malaria patients.

ABSTRACT:

Background

Artemisinins (ART) are the key component of the frontline antimalarial treatment, but their impact on Plasmodium falciparum sexual conversion rates in natural malaria infections remains unknown. This is an important knowledge gap because sexual conversion rates determine the relative parasite investment between maintaining infection in the same human host and transmission to mosquitoes.

Methods

The primary outcome of this study was to assess the impact of ART-based treatment on sexual conversion rates by comparing the relative transcript levels of pfap2-g and other sexual ring biomarkers (SRBs) before and after treatment. We analysed samples from previously existing cohorts in Vietnam, Burkina Faso and Mozambique (in total, n=109) collected before treatment and at 12 h intervals after treatment. As a secondary objective, we investigated factors that may influence the effect of treatment on sexual conversion rates.

Findings

In the majority of infections from the African cohorts, but not from Vietnam, we observed increased expression of pfap2-g and other SRBs after treatment. Estimated parasite age at the time of treatment was negatively correlated with the increase in pfap2-g transcript levels, suggesting that younger parasites are less susceptible to stimulation of sexual conversion.

Interpretation

We observed enhanced expression of SRBs after ART-based treatment in many patients, which suggests that in natural malaria infections sexual conversion rates can be altered by treatment. ART-based treatment reduces the potential of a treated individual to transmit the disease, but we hypothesise that under some circumstances this reduction may be attenuated by ART-enhanced sexual conversion.

Funding

Spanish Agencia Estatal de Investigación (AEI), European Regional Development Fund (ERDF, European Union), Belgium Development Cooperation (DGD), Canadian University Health Network (UHN), TransGlobalHealth-Erasmus Mundus (European Union).

SUBMITTER: Portugaliza HP

PROVIDER: S-EPMC9385555 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Plasmodium falciparum sexual conversion rates can be affected by artemisinin-based treatment in naturally infected malaria patients.

Portugaliza Harvie P HP Natama H Magloire HM Guetens Pieter P Rovira-Vallbona Eduard E Somé Athanase M AM Millogo Aida A Ouédraogo D Florence DF Valéa Innocent I Sorgho Hermann H Tinto Halidou H van Hong Nguyen N Sitoe Antonio A Varo Rosauro R Bassat Quique Q Cortés Alfred A Rosanas-Urgell Anna A

EBioMedicine 20220809

<h4>Background</h4>Artemisinins (ART) are the key component of the frontline antimalarial treatment, but their impact on Plasmodium falciparum sexual conversion rates in natural malaria infections remains unknown. This is an important knowledge gap because sexual conversion rates determine the relative parasite investment between maintaining infection in the same human host and transmission to mosquitoes.<h4>Methods</h4>The primary outcome of this study was to assess the impact of ART-based trea ...[more]

PMID: 35961203

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Dataset Information

Plasmodium falciparum sexual conversion rates can be affected by artemisinin-based treatment in naturally infected malaria patients.

Background

Methods

Findings

Interpretation

Funding

Publications

Plasmodium falciparum sexual conversion rates can be affected by artemisinin-based treatment in naturally infected malaria patients.

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