A systematic review on the prevalence and characteristics of canine visceral leishmaniasis in stray and owned dogs in Brazil.

Abstract

Canine visceral leishmaniasis (CVL) is a zoonosis caused by protozoa of the genus Leishmania. In urban environments, domestic dogs are the main reservoir, and canine cases may be associated with those in humans. This systematic review aimed to investigate the prevalence and epidemiological characteristics of CVL in stray and owned dogs in Brazil. Searches were conducted in November 2024 in PubMed, SciELO, and the BVS, and updated until December 2024, with no date restrictions for studies that answered the research question. Studies reporting the prevalence and characteristics of CVL in dogs in Brazil were included. A total of 45 studies published between 1985 and 2024 were included. Of these, 27 evaluated only owned dogs, with a higher prevalence of infection in male, adult, and senior dogs, mixed-breed, with short coats, and prevalence between 1.4 % to 76.0 %. Four studies analyzed only stray dogs, with infection predominantly in males, up to 5 years old, of defined breed, and prevalence between 54.4 % and 98.0 %. In 14 studies involving dogs of mixed or undefined origin, infection was more common in dogs aged 9 years or older, with higher seropositivity in those with short coat, with prevalence between 0.26 % to 75.3 %. Most infected dogs presented clinical signs, mainly dermatological, systemic, and were often subjected to euthanasia. The most identified species was L. infantum, although one study reported a possible infection by L. donovani. Our findings suggest that all groups are susceptible, with higher prevalence among stray dogs, reinforcing the need for epidemiological surveillance and control measures, given the relevance of CVL to public health.