Characterisation of an area of coexistent visceral and cutaneous leishmaniasis transmission in the State of Piauí, Brazil

BACKGROUND In Brazil, transmission of visceral and cutaneous leishmaniasis has expanded geographically over the last decades, with both clinical forms occurring simultaneously in the same area. OBJECTIVES This study characterised the clinical, spatial, and temporal distribution, and performed entomological surveillance and natural infection analysis of a leishmaniasis-endemic area. METHODS In order to characterise the risk of leishmaniasis transmission in Altos, Piaui, we described the clinical and sociodemographic variables and the spatial and temporal distribution of cases of American visceral leishmaniasis (AVL) and American cutaneous leishmaniasis (ACL) cases and identified potential phlebotomine vectors. FINDINGS The urban area concentrated almost 54% of ACL and 86.8% of AVL cases. The temporal and spatial distribution of AVL and ACL cases in Altos show a reduction in the number of risk areas, but the presence of permanent disease transmission foci is observed especially in the urban area. 3,808 phlebotomine specimens were captured, with Lutzomyia longipalpis as the most frequent species (98.45%). Of the 35 females assessed for natural infection, one specimen of Lu. longipalpis tested positive for the presence of Leishmania infantum and Leishmania braziliensis DNA. MAIN CONCLUSION Our results indicate the presence of risk areas for ACL and AVL in the municipality of Altos and highlight the importance of entomological surveillance to further understand a possible role of Lu. longipalpis in ACL transmission.