Dataset Information

Evaluating local vegetation cover as a risk factor for malaria transmission: a new analytical approach using ImageJ.

ABSTRACT:

Background

In places where malaria transmission is unstable or is transmitted under hypoendemic conditions, there are periods where limited foci of cases still occur and people become infected. These residual "hot spots" are likely reservoirs of the parasite population and so are fundamental to the seasonal spread and decline of malaria. It is, therefore, important to understand the ecological conditions that permit vector mosquitoes to survive and forage in these specific areas. Features such as local waterways and vegetation, as well as local ecology, particularly nocturnal temperature, humidity, and vegetative sustainability, are important for modeling local mosquito behavior. Vegetation around a homestead likely provides refuge for outdoor resting of these insects and may be a risk factor for malaria transmission. Analysis of this vegetation can be done using satellite information and mapping programs, such as Google Earth, but manual quantification is difficult and can be tedious and subjective. A more objective method is required.

Methods

Vegetation cover in the environment is reasonably static, particularly in and around homesteads. In order to evaluate and enumerate such information, ImageJ, an image processing software, was used to analyse Google Earth satellite imagery. The number of plants, total amount of vegetation around a homestead and its percentage of the total area were calculated and related to homesteads where cases of malaria were recorded.

Results

Preliminary results were obtained from a series of field trials carried out in South East Zambia in the Choma and Namwala districts from a base at the Macha District Hospital.

Conclusions

This technique is objective, clear and simple to manipulate and has potential application to determine the role that vegetation proximal to houses may play in affecting mosquito behaviour, foraging and subsequent malaria incidence.

SUBMITTER: Ricotta EE

PROVIDER: S-EPMC4007634 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Publications

Evaluating local vegetation cover as a risk factor for malaria transmission: a new analytical approach using ImageJ.

Ricotta Emily E EE Frese Steven A SA Choobwe Cornelius C Louis Thomas A TA Shiff Clive J CJ

Malaria journal 20140313

<h4>Background</h4>In places where malaria transmission is unstable or is transmitted under hypoendemic conditions, there are periods where limited foci of cases still occur and people become infected. These residual "hot spots" are likely reservoirs of the parasite population and so are fundamental to the seasonal spread and decline of malaria. It is, therefore, important to understand the ecological conditions that permit vector mosquitoes to survive and forage in these specific areas. Feature ...[more]

PMID: 24620929

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Dataset Information

Evaluating local vegetation cover as a risk factor for malaria transmission: a new analytical approach using ImageJ.

Background

Methods

Results

Conclusions

Publications

Evaluating local vegetation cover as a risk factor for malaria transmission: a new analytical approach using ImageJ.

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