Studies on seasonal fluctuation of different indices related to filarial vector, Culex quinquefasciatus around foothills of Susunia of West Bengal, India.

Abstract: Objective: To collect information on the seasonal activity of filarial vector around foothills of Susunia of West Bengal, India. Methods: Indoor-resting mosquitoes were collected from the human habitations of 16 villages. Collected mosquitoes were identified and examined for different parameters following standard methods recommended by World Health Organization and pioneer workers. Results: Overall man hour density, infection rate, infectivity rate, human blood index and daily mortality rate of the vector were assessed as 10.54%, 6.31%, 1.38%, 77.33% and 13.00%, respectively, which were 12.17%, 8.63%, 2.26%, 100.00% and 17.00%, respectively in the summer season. Average load of microfilaria, 1 st stage, 2 nd stage and 3 rd stage larvae of Wuchereria bancrofti in infected vectors were 10.02, 7.50, 5.56 and 4.68, respectively, which were 11.58, 9.90, 6.27 and 5.44, respectively in summer. Among the searched shelters 63.37%, 8.16% and 2.08% were found to be invaded by any vector, infected vector and infective vector, respectively, which were 68.75%, 12.76% and 3.91%, respectively in summer. Conclusions: Different indices related to the vector were much higher in summer, which indicates that, summer is the most favorable season for transmission of lymphatic filariasis in the study area. Available data will help to formulate an effective vector control measure. [ABSTRACT FROM AUTHOR]