Seroepidemiological survey for visceral leishmaniasis in dogs from an unaffected municipality of RS in the period 2021-2024

Abstract

Canine visceral leishmaniasis (CVL) is a vector-borne parasitic disease that is expanding geographically, with autochthonous cases recorded in Rio Grande do Sul (RS) since 2008. Indigenous areas such as the municipalities of Pelotas, Rio Grande and Bagé are not part of active epidemiological surveillance for CVL, but the region has predisposing factors for the spread of the disease. The aim of this study was therefore to carry out a seroepidemiological survey of serum samples from dogs treated at a veterinary hospital in a disease-free area. The survey took place over a three-year period, following the current Ministry of Health (MoH) protocol. A total of 2,365 samples from asymptomatic animals were tested, of which 0.8% were seroreactive in the Dual Path Platform (DPP®) screening test. Of the samples that reacted to the DPP®, 37% were seroreactive to the ELISA (Bio-Manguinhos®), one was inconclusive (5.2%), 42% were negative and in 21% no confirmatory test was carried out. It can be concluded that Pelotas, Rio Grande and Bagé, the places of residence of seroreagent animals and CVL-free municipalities, have seroreagent dogs circulating according to the current MH protocol and require attention from epidemiological surveillance.