Identification of risk areas for visceral leishmaniasis in Teresina, Piaui State, Brazil.

This study used spatial analysis to identify areas at greatest risk of visceral leishmaniasis (VL) in the urban area of Teresina, Brazil during 2001-2006. The results from kernel ratios showed that peripheral census tracts were the most heavily affected. Local spatial analysis showed that in the beginning of the study period local clusters of high incidence of VL were mostly located in the southern and northeastern parts of the city, but in subsequent years those clusters also appeared in the northern region of the city, suggesting that the pattern of VL is not static, and the disease may occasionally spread to other areas of the municipality. We also observed a spatial correlation between VL rates and all socioeconomic and demographic indicators evaluated (P < 0.01). The concentration of interventions in high-risk areas could be an effective strategy to control the disease in the urban setting.