Dataset Information

Biodiversity can help prevent malaria outbreaks in tropical forests.

ABSTRACT:

Background

Plasmodium vivax is a widely distributed, neglected parasite that can cause malaria and death in tropical areas. It is associated with an estimated 80-300 million cases of malaria worldwide. Brazilian tropical rain forests encompass host- and vector-rich communities, in which two hypothetical mechanisms could play a role in the dynamics of malaria transmission. The first mechanism is the dilution effect caused by presence of wild warm-blooded animals, which can act as dead-end hosts to Plasmodium parasites. The second is diffuse mosquito vector competition, in which vector and non-vector mosquito species compete for blood feeding upon a defensive host. Considering that the World Health Organization Malaria Eradication Research Agenda calls for novel strategies to eliminate malaria transmission locally, we used mathematical modeling to assess those two mechanisms in a pristine tropical rain forest, where the primary vector is present but malaria is absent.

Methodology/principal findings

The Ross-Macdonald model and a biodiversity-oriented model were parameterized using newly collected data and data from the literature. The basic reproduction number ([Formula: see text]) estimated employing Ross-Macdonald model indicated that malaria cases occur in the study location. However, no malaria cases have been reported since 1980. In contrast, the biodiversity-oriented model corroborated the absence of malaria transmission. In addition, the diffuse competition mechanism was negatively correlated with the risk of malaria transmission, which suggests a protective effect provided by the forest ecosystem. There is a non-linear, unimodal correlation between the mechanism of dead-end transmission of parasites and the risk of malaria transmission, suggesting a protective effect only under certain circumstances (e.g., a high abundance of wild warm-blooded animals).

Conclusions/significance

To achieve biological conservation and to eliminate Plasmodium parasites in human populations, the World Health Organization Malaria Eradication Research Agenda should take biodiversity issues into consideration.

SUBMITTER: Laporta GZ

PROVIDER: S-EPMC3605282 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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Publications

Biodiversity can help prevent malaria outbreaks in tropical forests.

Laporta Gabriel Zorello GZ Lopez de Prado Paulo Inácio Knegt PI Kraenkel Roberto André RA Coutinho Renato Mendes RM Sallum Maria Anice Mureb MA

PLoS neglected tropical diseases 20130321 3

<h4>Background</h4>Plasmodium vivax is a widely distributed, neglected parasite that can cause malaria and death in tropical areas. It is associated with an estimated 80-300 million cases of malaria worldwide. Brazilian tropical rain forests encompass host- and vector-rich communities, in which two hypothetical mechanisms could play a role in the dynamics of malaria transmission. The first mechanism is the dilution effect caused by presence of wild warm-blooded animals, which can act as dead-end ...[more]

PMID: 23556023

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Dataset Information

Biodiversity can help prevent malaria outbreaks in tropical forests.

Background

Methodology/principal findings

Conclusions/significance

Publications

Biodiversity can help prevent malaria outbreaks in tropical forests.

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