Susceptibilidade de quatis (Nasua nasua) de vida livre ao vírus da influenza A em parque urbano de Belo Horizonte

Abstract

Coatis (Nasua nasua) are carnivorous members of the Procyonidae family and are present in high densities in several urban centers. They have gregarious and generalist habits and may be affected by infectious diseases, acting as potential asymptomatic reservoirs of pathogenic agents. In the last two decades, wildlife has given rise to approximately 75% of existing zoonotic diseases. In this context, influenza A is a disease of global distribution that infects a wide spectrum of hosts and occurs annually on a seasonal basis, causing epidemics. Waterfowl are considered the natural reservoir of the disease and contribute significantly to its spread. The evolution of influenza viruses (IAVs) is highly associated with their genomic nature and antigenic drift and shift events. Pigs (Sus scrofa domesticus) play an important role in antigenic change, since they can be infected by IAVs from birds and humans due to the presence of α-2,3 and α-2,6 sialic acid receptors. In a similar way, studies describe that raccoons (Procyon lotor), phylogenetically close to coatis, also have both types of sialic acid receptors in their respiratory system, therefore can be potentatilly coinfected by IAVs of different origins. The ability of IAVs to periodically spread to originally non-host species poses a threat to animal and human health. In this context, the present project aimed to study the susceptibility of the coatis population (Nasua nasua) from the Mangabeiras Municipal Park, Minas Gerais, to infection by IAVs. For this, hemagglutination inhibition analysis, real-time RT-PCR and lectin histochemistry techniques were performed. Serum samples from coatis captured in 2013, 2014, 2018, 2019 and 2021 were analyzed for H1N1pdm09, H3N2 and human H1N1 seasonal subtypes prior to H1N1pdm09. The results showed constant exposure of the coatis population to the viral subtypes studied, with a prevalence of 92.4% (134/145), as well as high antibody titers in different age groups and genders. Also, in the direct diagnosis of the virus, carried out from the biological samples obtained in 2021, presence of viral RNA in the oropharyngeal swab samples was found in 23.81% (15/63) of the animals. The α-2,6 and α-2,3 sialic acid receptors were detected in the respiratory system from coatis carcasses found in the park. The results suggest the susceptibility of coatis to IAV subtypes of different origins, as well as possible exposure to viruses in the park from the human population and possible asymptomatic intraspecific transmission. More studies should be carried out in order to understand the epidemiological importance of the species in the transmission cycle of this zoonotic agent. Management measures must be carried out in order to reduce the exposure of coatis to pathogens of human origin, minimizing the possibility of viral spillover events.