Geographical Distribution and Seasonal Prevalence of Aedes aegypti in Urban Lahore, Pakistan

Objective: Seasonal prevalence of female Aedes aegypti was studied to determine its habits and its transmission season in Lahore, Pakistan.

Methods: The study was carried out by placing black modified ovitraps indoor & outdoor in 25 different households per town in ten administrative areas of the city. The placement of ovitraps was done by stratified random sampling method. Data was collected on weekly basis and monthly indices of adult and larvae were calculated. High (>9 Breteau Index) indoor prevalence of adult was found in Data Gunj Bakhsh and Iqbal Town, moderate (5 to 9 Breteau Index) was observed in Aziz Bhatti town only.

Results: In all other seven study areas indoor prevalence of adult was found low (<5 Breteau Index). Regarding outdoor prevalence of adults, high (>9 Breteau Index) was not detected from any area, moderate (5 to 9 Breteau Index) was observed in Aziz Bhatti, Gulberg, Shalimar and Nishtar towns. In all other six study areas outdoor prevalence of adult was found low (<5 Breteau Index). During the months September, October, November, March and April Aedes aegypti density was found high and no adult or larva was found during the months of December, January, February, June and July. Prevalence of Aedes aegypti in various seasons was detected significantly (p< 0.05) different.

Conclusion: It is concluded that A. aegypti is widely distributed in all the towns of Lahore but some areas like Iqbal town and Data Gunj Baksh town had high indoor prevalence.