Researchers believe the widespread appearance of the novel coronavirus among white-tailed deer in Iowa is due to “multiple human-to-deer spillover events and deer-to-deer transmission.” The finding raises concerns about “the potential for spillover to other animals and spillback into humans,” researchers found.
In a study in preprint led by Penn State University researchers Suresh Kuchipudi and Vivek Kapur, biologists found a third of white-tailed deer (Odocoileus virginianus) in Iowa tested positive for SARS-CoV-2, the virus that causes COVID-19. Based on the geography of clusters of both deer and human occurrences of the virus, the researchers believe it is likely that the deer contracted the virus from humans.
A previous study this year by the USDA Animal and Plant Health Inspection Service found antibodies for the virus among less than half the deer in four states. But while that study confirmed that deer had been exposed, but not infected, this study showed active infection. Scientists worry deer could serve as a reservoir for the virus, allowing it to evolve into a more virulent strain that could infect people and be resistant to current treatments.
“If deer can transmit the virus to humans, it’s a game changer,” Tony Goldberg, University of Wisconsin-Madison veterinary researcher Tony Goldberg told the New York Times. “To have a wildlife species become a reservoir after transmission from humans is very rare and unlucky, as if we needed more bad luck.”
The authors say their findings “highlight an urgent need for a robust and proactive ‘One Health’ approach to obtaining a better understanding of the ecology and evolution of SARS-CoV-2.”