Dataset Information

Choosing interventions to eliminate forest malaria: preliminary results of two operational research studies inside Cambodian forests.

ABSTRACT:

Background

Rapid elimination of Plasmodium falciparum malaria in Cambodia is a goal with both national and international significance. Transmission of malaria in Cambodia is limited to forest environments, and the main population at risk consists of forest-goers who rely on forest products for income or sustenance. The ideal interventions to eliminate malaria from this population are unknown.

Methods

In two forested regions of Cambodia, forest-goers were trained to become forest malaria workers (FMWs). In one region, FMWs performed mass screening and treatment, focal screening and treatment, and passive case detection inside the forest. In the other region, FMWs played an observational role for the first year, to inform the choice of intervention for the second year. In both forests, FMWs collected blood samples and questionnaire data from all forest-goers they encountered. Mosquito collections were performed in each forest.

Results

Malaria prevalence by PCR was high in the forest, with 2.3-5.0% positive for P. falciparum and 14.6-25.0% positive for Plasmodium vivax among forest-goers in each study site. In vectors, malaria prevalence ranged from 2.1% to 9.6%, but no P. falciparum was observed. Results showed poor performance of mass screening and treatment, with sensitivity of rapid diagnostic tests equal to 9.1% (95% CI 1.1%, 29.2%) for P. falciparum and 4.4% (95% CI 1.6%, 9.2%) for P. vivax. Malaria infections were observed in all demographics and throughout the studied forests, with no clear risk factors emerging.

Conclusions

Malaria prevalence remains high among Cambodian forest-goers, but performance of rapid diagnostic tests is poor. More adapted strategies to this population, such as intermittent preventive treatment of forest goers, should be considered.

SUBMITTER: Kunkel A

PROVIDER: S-EPMC7818569 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Publications

Choosing interventions to eliminate forest malaria: preliminary results of two operational research studies inside Cambodian forests.

Kunkel Amber A Nguon Chea C Iv Sophea S Chhim Srean S Peov Dom D Kong Phanith P Kim Saorin S Im Sarun S Debackere Mark M Khim Nimol N Popovici Jean J Srun Sreynet S Vantaux Amélie A Guintran Jean-Olivier JO Witkowski Benoit B Piola Patrice P

Malaria journal 20210120 1

<h4>Background</h4>Rapid elimination of Plasmodium falciparum malaria in Cambodia is a goal with both national and international significance. Transmission of malaria in Cambodia is limited to forest environments, and the main population at risk consists of forest-goers who rely on forest products for income or sustenance. The ideal interventions to eliminate malaria from this population are unknown.<h4>Methods</h4>In two forested regions of Cambodia, forest-goers were trained to become forest m ...[more]

PMID: 33472630

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Dataset Information

Choosing interventions to eliminate forest malaria: preliminary results of two operational research studies inside Cambodian forests.

Background

Methods

Results

Conclusions

Publications

Choosing interventions to eliminate forest malaria: preliminary results of two operational research studies inside Cambodian forests.

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