Abstract

Introduction: Installation of deltamethrin-impregnated screens and curtains was assessed as a preventive measure against transmission of anthroponotic cutaneous leishmaniasis (ACL) by Phlebotomus sergenti in Bam, a well-known focus of ACL in Iran with a population of nearly 100 000. Methods: This was a quasi-experiement based on official data from an ACL control program in which one section of the city with about one-quarter of the population received the intervention. In the analysis, the rest of the city was used as control. Data covered June 2007 through October 2010. Results: Comparison of cumulative incidence between the intervention and control areas before and after installation indicate a significant differential reduction in the cumulative ACL incidence in the intervention area and a reversal of the relative risk, beginning four months after the completion of installation, from RR = 1.14 (95 CI:1.05-1.23) to RR = 0.84 (95 CI:0.72-0.98). Results also indicate a return to a higher cumulative relative risk, RR = 1.51 (95 CI:1.30-1.77), several months after the loss of the preventive effect. Conclusions: Findings indicate the short-term effectiveness of such preventive measures but highlight the necessity of long-term, sustainable strategies. Results also suggest that shrinkage in the human reservoir pool in response to the intervention may play a significant role in prolongation of the preventive effect beyond the insecticidal life of impregnated materials in foci of anthroponotic cutaneous leishmaniasis and possibly anthroponotic visceral leishmaniasis due to L. donovani.