While COVID cases are going up in humans lately, animals have to worry about the virus too — and sick wildlife pose a threat to humans, because they can spread pathogens back and forth, giving them the opportunity to evolve new, more infectious mutations. A number of species can be infected with COVID-19, from deer and mink to dogs and rats.
A recent study finds that almost half of the species examined in Virginia were either previously or are currently infected with SARS-CoV-2, the virus responsible for COVID-19. The authors suspect the animals were originally infected by humans.
Published in the journal Nature Communications, the paper includes findings from Virginia Tech researchers who performed 789 nasal and oral swabs and 126 blood samples on 23 species of animals, from Eastern cottontail rabbits and raccoons to opossums and groundhogs. The study was carried out in the Washington DC metropolitan area from May 2022 to September 2023. Six of the species showed signs of current SARS-CoV-2 infection, while another five had antibodies indicating previous SARS-CoV-2 infections. Importantly, the scientists observed previously unreported viral mutations in the common SARS-CoV-2 strains similar to markers in the Omicron variant widely circulating among humans at that time. This suggests widespread human-to-animal transmission.
"The virus can jump from humans to wildlife when we are in contact with them, like a hitchhiker switching rides to a new, more suitable host," co-senior author Dr. Carla Finkielstein said in a Virginia Tech press release. "The virus aims to infect more humans, but vaccinations protect many humans. So, the virus turns to animals, adapting and mutating to thrive in the new hosts."
So far, there is no evidence that animals have spread the virus back to humans, though it is still possible. In the meantime, the researchers say there is no need to fear interactions with wildlife.
