A report on the indoor residual spraying (IRS) in the control of Phlebotomus argentipes, the vector of visceral leishmaniasis in Bihar (India): an initiative towards total elimination targeting 2015 (Series-1)

Abstract

Background & objectives: Visceral leishmaniasis, commonly known as kala-azar is endemic inBihar state, India. Current vector control programme in Bihar focuses mainly on spraying thesandfly infested dwellings with DDT. The Government of India in collaboration with WHO hasfixed the target 2015 for total elimination of kala-azar. The present study was carried out to see theimpact of DDT and improved IEC in the containment of vector density vis-à-vis disease transmission.Methods: Before the start of the spraying operations training was imparted to all the medical andparamedical personnel regarding the methods of spraying operations. Pre- and post-sandfly densitywas monitored in four selected districts. Incidences of kala-azar cases were compared for pre- andpost-spray periods. Social acceptability and perceptions of households was collected throughquestionnaires from 500 randomly selected households in the study districts.Results: House index in three study districts reduced considerably during post-spray when comparedto pre-spray. Kala-azar incidence in many districts was reduced after the DDT spray. Either partialor complete refusal was reported in 14.4%, while 35% were not satisfied with the suspensionconcentration and coverage; and 46.6% were found satisfied with the spraying procedure.Interpretation & conclusion: Strengthening the IEC activities to sensitise the community, propertraining of health personnel, monitoring of spray, good surveillance, proper treatment of cases andtwo rounds of DDT spray with good coverage in the endemic districts up to three years are essentialto achieve the desired total elimination of kala-azar in Bihar state.

Keywords

• Bihar
• DDT
• IEC
• indoor residual spray
• Phlebotomus argentipes
• visceral leishmaniasis