Dataset Information

Mosquito Behavior Change After Distribution of Bednets Results in Decreased Protection Against Malaria Exposure.

ABSTRACT:

Background

Behavioral resilience in mosquitoes poses a significant challenge to mosquito control. Although behavior changes in anopheline vectors have been reported over the last decade, there are no empirical data to suggest they compromise the efficacy of vector control in reducing malaria transmission.

Methods

In this study, we quantified human exposure to both bites and infective bites of a major malaria vector in Papua New Guinea over the course of 4 years surrounding nationwide bednet distribution. We also quantified malaria infection prevalence in the human population during the same time period.

Results

We observed a shift in mosquito biting to earlier hours of the evening, before individuals are indoors and protected by bednets, followed by a return to preintervention biting rates. As a result, net users and non-net users experienced higher levels of transmission than before the intervention. The personal protection provided by a bednet decreased over the study period and was lowest in the adult population, who may be an important reservoir for transmission. Malaria prevalence decreased in only 1 of 3 study villages after the distribution.

Discussion

This study highlights the necessity of validating and deploying vector control measures targeting outdoor exposure to control and eliminate malaria.

SUBMITTER: Thomsen EK

PROVIDER: S-EPMC5388271 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Publications

Mosquito Behavior Change After Distribution of Bednets Results in Decreased Protection Against Malaria Exposure.

Thomsen Edward K EK Koimbu Gussy G Pulford Justin J Jamea-Maiasa Sharon S Ura Yangta Y Keven John B JB Siba Peter M PM Mueller Ivo I Hetzel Manuel W MW Reimer Lisa J LJ

The Journal of infectious diseases 20170301 5

<h4>Background</h4>Behavioral resilience in mosquitoes poses a significant challenge to mosquito control. Although behavior changes in anopheline vectors have been reported over the last decade, there are no empirical data to suggest they compromise the efficacy of vector control in reducing malaria transmission.<h4>Methods</h4>In this study, we quantified human exposure to both bites and infective bites of a major malaria vector in Papua New Guinea over the course of 4 years surrounding nationw ...[more]

PMID: 28007921

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Project description:Rapid transformation of natural ecosystems changes ecological conditions for important human disease vector species; therefore, an essential task is to identify and understand the variables that shape distributions of these species to optimize efforts toward control and mitigation. Ecological niche modeling was used to estimate the potential distribution and to assess hypotheses of niche similarity among the three main malaria vector species in northern Colombia: Anopheles nuneztovari, An. albimanus, and An. darlingi. Georeferenced point collection data and remotely sensed, fine-resolution satellite imagery were integrated across the Urabá -Bajo Cauca-Alto Sinú malaria endemic area using a maximum entropy algorithm. Results showed that An. nuneztovari has the widest geographic distribution, occupying almost the entire study region; this niche breadth is probably related to the ability of this species to colonize both, natural and disturbed environments. The model for An. darlingi showed that most suitable localities for this species in Bajo Cauca were along the Cauca and Nechí river. The riparian ecosystems in this region and the potential for rapid adaptation by this species to novel environments, may favor the establishment of populations of this species. Apparently, the three main Colombian Anopheles vector species in this endemic area do not occupy environments either with high seasonality, or with low seasonality and high NDVI values. Estimated overlap in geographic space between An. nuneztovari and An. albimanus indicated broad spatial and environmental similarity between these species. An. nuneztovari has a broader niche and potential distribution. Dispersal ability of these species and their ability to occupy diverse environmental situations may facilitate sympatry across many environmental and geographic contexts. These model results may be useful for the design and implementation of malaria species-specific vector control interventions optimized for this important malaria region.

Dataset Information

Mosquito Behavior Change After Distribution of Bednets Results in Decreased Protection Against Malaria Exposure.

Background

Methods

Results

Discussion

Publications

Mosquito Behavior Change After Distribution of Bednets Results in Decreased Protection Against Malaria Exposure.

Similar Datasets

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