Prevalence of rat fleas in and around Delhi (India) area and their susceptibility status to insecticides.

A rapid survey in Delhi and surrounding areas was undertaken in September 1994, during plague outbreak in District Beed (Maharashtra) and Surat (Gujarat) to monitor rodent/flea population and to determine susceptibility status of fleas to insecticides. The five rodent species in order of their prevalence were Rattus rattus (86.06%), Mus musculus (15.33%), Suncus murinus (2.47%), Bandicoota indica (0.48%) and B. bengalensis (0.48%). Two flea species, Xenopsylla cheopis and X. astia, were captured from these rodents. The absolute flea index was found to be ranging between 0.08 to 4.0 in various localities. X. cheopis and X. astia indexes were ranging between 0.22 to 2.08 and 0.08 to 4.0, respectively. Susceptibility test results with X. cheopis collected and reared in the laboratory revealed that it is resistant to DDT and Dieldrin, tolerant to Malathion and susceptible to K-othrin (Deltamethrin).