Study of aedes larval density in Alwar district, Rajasthan, India

Abstract

Rajasthan is one of the dengue endemic states of India. Very few studies have been published on entomological aspects of dengue in this state. Owing to water scarcity, inhabitants in desert areas overstore domestic water which leads to the persistence of dengue vectors within the domestic premises. To study the significance of entomological surveillance, the house index (HI), container index (CI), and Breteau index (BI) were determined to estimate the degree of a major dengue outbreak. The HI, CI, and BI were determined in a primary health center (PHC) in the village of Haldina, Leeli and Balana by carrying out entomological surveillance, which involved door-to-door search for immature stages of Aedes spp. mosquitoes by trained field workers. A total of 150 houses were searched for detection of immatures of Aedes mosquitoes. Infestation indices are calculated as the percentage of positive houses, or percentage of positive containers, and are used to guide control actions and to issue alerts. The Balana village were having highest larval indices i.e. house index=32, container index =15.3 and breteau index =42 followed by Leeli and Haldina villages respectively. Because no specific medicine and vaccines are available to treat dengue fever and dengue hemorrhagic fever, entomological surveillance and its significance can be used to halt the outbreak.