Tropical Medicine & Surgery

Abstract

Comparative Studies of Different Indices Related to Filarial Vector of a Rural and an Urban Area of West Bengal, India

Goutam Chandra, Manas Paramanik, Samir Kumar Mondal and Arup Kumar Ghosh

Background: Despite of all types of efforts, mosquito born disease like lymphatic filariasis seems to cause new disease burden in many countries. Proper information about the vector of these diseases is necessary to stop the transmission, but sometime information on vector is scanty from many areas. Present study is designed to collect comparative information about the filarial vector from rural and urban areas of West Bengal in India.
Methods: Regular collection of indoor-resting mosquitoes was done from the human habitations of Kolkata (urban area) and Tenya of Murshidabad district (rural area) for 2 years. Collected mosquitoes were identified and examined for different parameters following standard methods recommended by World Health Organization and pioneer workers of the field.
Results: In both the areas Wuchereria bancrofti was identified as the causative parasite of filariasis and Culex quinquefasciatus as the vector. In the urban area, overall man hour density, infection rate, infectivity rate and daily mortality rate of the vector was assessed as 27.56, 3.49%, 0.34% and 13% respectively, which was 11.86, 1.41%, 0.14% and 15% respectively in rural area. Average load of microfilaria, 1st stage, 2nd stage and 3rd stage parasite larvae in infected vectors were 8.10, 7.37, 5.38 and 2.75 respectively in urban area, which was 6.45, 5.40, 4.67 and 2.33 respectively in rural area. Among the searched shelters in urban area 4.27%, 8.85% and 1.46% were found to be invaded by 10 or more vector, infected vector and infective vector respectively, which were 1.56%, 2.08% and 0.31% respectively in rural area.
Conclusion: Different indices related to the vector mosquito were much higher in urban area of Kolkata than rural area of Tenya in Murshidabad, which indicates that, situation is more favourable in urban study areas for transmission of lymphatic filariasis than the rural one, though the situation in the rural area cannot be neglected. Available data will help to formulate an effective management strategy in those areas.