Visceral leishmaniasis and vulnerability conditions in an endemic urban area of Northeastern Brazil.

BACKGROUND: Visceral leishmaniasis (VL) is considered an urban endemic that may be related to sociodemographic factors and urban infrastructure. The objective of this study was to analyze the conditions of vulnerability and the incidence of VL, and to identify the spatiotemporal pattern of the disease. METHODS: Data on reported cases of VL were collected from 2007 to 2016. Thematic maps on the spatiotemporal distribution were produced using values normalized by the area of the neighborhoods. The primary indicators of vulnerability were normalized for later construction of the synthetic indicators of vulnerability of social structure, household structure, and urban infrastructure, and from these, a vulnerability index was developed. The bivariate global Moran index was used to verify the existence of spatial autocorrelation between the incidence of VL and the conditions of vulnerability, while the bivariate local Moran index was used to identify the existence of spatial clusters. RESULTS: The 695 cases reported presented a diffuse distribution when the spatial pattern was evaluated. The incidence of the disease was correlated with worsened living conditions. Statistically significant clusters were revealed between the incidence of the disease and the vulnerability indicators of social structure, household structure, urban infrastructure and composite vulnerability index. CONCLUSION: Addressing the local vulnerability conditions is important to the understanding of the distribution of visceral leishmaniasis, identifying the most susceptible areas, and planning control strategies.

Occurrence of Lutzomyia longipalpis Lutz & Neiva 1912 and Cerdocyon thous Linnaeus 1977, in a visceral leishmaniasis endemic area in Brazil.

Cerdocyon thous presents a wide geographic distribution in Brazil and its role as a possible Leishmania infantum reservoir in a visceral leishmaniasis (VL) transmission cycle regardless of dogs (Canis familiaris) has been discussed. From this perspective, this work describes the occurrence and use of the habitat by Cerdocyon thous in a Lutzomyia longipalpis occurrence area Teresina (Piaui - Brazil), VL endemic region. Three specimens of C. thous were monitored with the use of radio telemetry and trails and footprints, seeking to find possible natural dens in order to collect the sanflies from the site. Luminous CDC and Damasceno traps were simultaneously installed at the visited sites, where two specimens of L. longipalpis and one L. termitophila were captured. The identification of the dens and trails, allows us to infer that the dens are not used only by the C. thous. Finding the VL vector in natural C. thous natural dens, reinforces the hypothesis of transmission of Le. infantum in the outskirts of the large urban centers, in a cycle that independs from dogs.