Efficacy of light-traps in sampling malaria vectors in different ecological zones in central India

This preliminary field study was designed chiefly to test the efficiency of the light-trap as a tool for sampling malaria vectors, in tribal villages located in different ecological settings in comparison with indoor resting collections as an alternative method. Anopheles culicifacies, a known malaria vector, was the most prevalent species in the study villages and more than 80% of trap catches were obtained before midnight with peak activity during dusk. Reproductive status of trapped specimens revealed proportional representations of unfed, freshly fed, and gravid females. Another vector, An. fluviatilis was found in small numbers by both the methods. Thus the trap could give a reliable and unbiased sample of vector population. Seven species were abundant in the light-trap catches while only four in the indoor resting collections indicates the usefulness of the light-trap for sampling exophilic species. The study revealed that light-traps did not have any bias in favor of any particular species. The method may be useful for assessing the night time densities of different species or the fluctuation of a species at different dates and village to village variations. Light-traps could be used for sampling both endophilic and exophilic anophelines.