B. MAHANTA, R. HANDIQUE*, K. NARAIN, P. DUTTA AND J. MAHANTA
Abstract
Assam is the most populous state in north-eastern part of India and produces more than 70% of India's tea. Tea is a labour intensive agro industry and filariasis is mostly localized among the tea garden workers in Assam. The workers live inside the gardens in colonies. Studies conducted in two consecutive years revealed that among the resting Cx. quinquefasciatus, 1.6% were infected with filaria and an average of 3.42 larvae are detected per mosquito. The probability of infected mosquitoes surviving 13 days (average duration of extrinsic cycle of Wuchereria bancrofti in Cx. quinquefasciatus) was 0.17. Expectation of infective life was 1.04 days for Indoor resting female mosquitoes. Monthly variations in daily survival rates of indoor resting Cx. quinquefasciatus ranged from 81.5% to 92.3%. The estimated adult survival rate of indoors resting mosquitoes was 87.6%. In both the year no infection was detected during February and March in indoor resting mosquitoes and infection rate remained low up to May (Average infection in April 0.72% and in May 0.48%).