Scientists have evidence that SARS-CoV-2 spreads explosively in white-tailed deer and that the virus is widespread in this deer population across the United States.
One-third of Iowa deer sampled over a period of nine months had active SARS-CoV-2 infections with a peak of 80 percent testing positive between November and January, according to a preprint study that has not yet been peer-reviewed or published.
This latest study builds on a study published by the National Academy of Sciences that shows one-third of deer in other US states were exposed to the virus and developed antibodies, but it differs in showing the high rate of active infections.
Another study, published in September 2020, suggested SARS-CoV-2 could easily bind to and enter the deer’s cells. A recent survey of white-tailed deer in the Northeast and Midwest found that nearly 40 percent of them had antibodies against SARS-CoV-2.
White-tail deer are abundant in North America and a popular target for hunters. They are also highly susceptible to SARS-CoV-2 and could pick up the virus in any number of ways, according to The Guardian.
The scientists say the deer probably picked up the virus through exposure to people, though how is unclear, reports the Duluth News Tribune. One possibility is by encountering human fluids, perhaps the urine of hunters or hikers.
“Right now that’s really the million-dollar question—how are they getting exposed,” says one of the co-authors, Rachel Ruden of Iowa State.
And the big concern to come out of this study is the suggestion that white-tailed deer could become what’s known as a reservoir for SARS-CoV-2, reports NPR.org. That is, the animals could carry the virus indefinitely and spread it back to humans periodically.
If that’s the case, it would essentially dash any hopes of eliminating or eradicating the virus in the U.S. — and therefore from the world — says veterinary virologist Suresh Kuchipudi at Penn State, who co-led the study.
“If the virus has opportunities to find an alternate host besides humans, which we would call a reservoir, that will create a safe haven where the virus can continue to circulate even if the entire human population becomes immune,” he says. “And so it becomes more and more complicated to manage or even eradicate the virus.”
