Study on the Impact of Insufflation and Residual Insecticide Spray against Rat Fleas and Present Susceptibility Status of Rodent Fleas to various Insecticides in Surat, Gujarat

Impact of insufflation with malathion 5% powder and residual insecticide spray with malathion 5% w.d.p. on rodent fleas in Surat rural areas and present susceptibility status of fleas to various insecticides from 2003 to 2009 in Surat urban and rural areas were evaluated to ascertain the appropriate use of insecticides used for residual indoor spray(IRS) and insufflations (rodent burrow dusting) to obtain cent percent mortality of the target population particularly Xenopsylla cheopis (Rothschild), the efficient vector for the transmission of Yersinia pestis infection. There is a widespread multiple resistance observed among the fleas from different eco zones. Similar situation was observed in plague endemic areas of Beed, Maharashtra state, where bubonic plague outbreak and rodent epizootics were reported during 1994. Susceptibility test results revealed that Xenopsylla cheopis developed resistance for 1 hour exposure period to DDT-4% in Surat urban and rural areas (Mean mortality-50.6% and 45.5% respectively), Malathion-5% (Mean mortality-35.8% and 48.8% respectively), Deltamethrin 0.05% (Mean mortality-61.4% and 74.2 % respectively). Mortality against Permethrin 0.75% was 89% in rural and 90.7% in urban areas, whereas 59.6 and 82.3 percent mortality were recorded for Cyfluthrin 0.155%.