Cat-transmitted sporotrichosis by Sporothrix brasiliensis: Focus on its potential transmission routes and epidemiological profile.

Cat-transmitted sporotrichosis (CTS) by Sporothrix brasiliensis is an important epizoonosis with alarming numbers of cases involving felines, canines, and humans. Considering the increasing incidence of CTS this study sought to elucidate the epidemiological characteristics of cats with sporotrichosis and evaluate the potential transmission routes of S. brasiliensis in several biological samples from cats with sporotrichosis. Samples were collected from ulcerated skin lesions, front paws, nasal cavity, and droplets collected from sick cats during sneezing episodes in a veterinarian university hospital, in the city of Curitiba, southern Brazil, between June 2021 and April 2022. A total of 100 cats with sporotrichosis were enrolled in the study. The fungus was isolated in 60% of samples from the nasal cavity and 71% of respiratory droplets. The growth of S. brasiliensis on the right and left front paw was observed in 41% of the cats included, and in 38%, there was growth of the fungus even without an apparent lesion on the paw. Of the infected cats, 64% had multifocal lesions throughout the body. The identification of S. brasiliensis in samples of exudate, paws, nasal cavity, and sneeze droplets suggests that transmission can occur not only through classic routes, but also through the movement of the infected cat, as well as through respiratory droplets expelled by the cat sneezing or nasal drip. Furthermore, the presence of S. brasiliensis on the paws of sick cats indicates the possibility that the fungus is being disseminated in the environment in which the animal lives.