Analysis

White-tailed deer are getting coronavirus infections: How big of a problem is that?

By Matt Field, August 2, 2021

Since making the leap to people, the SARS-CoV-2 virus that causes COVID-19 has wrought havoc on human populations. Now the virus appears to be surging among some wild animals as well. A new US government study of white-tailed deer reported that many had been infected, raising the potential that even if the virus is eventually controlled or even eradicated in humans, another common animal could provide it a reservoir and spawn future outbreaks.

The US Department of Agriculture’s Animal and Plant Health Inspection Service tested 481 samples collected between January 2020 and March 2021 from deer in Illinois, New York, Michigan, and Pennsylvania and found that 33 percent tested positive for antibodies to the COVID-19 virus. While many animals appeared to have been infected—more than 60 percent of samples in Michigan tested positive, for example—the agency said there were no reports of deer appearing clinically ill.

Researchers want to know how the deer got infected in the first place. Linda Saif, a virologist at The Ohio State University told Nature that a critical question is “how the virus spread to deer and if it will spread from infected deer to other wildlife or to domestic livestock such as cattle.” The animal and plant health service said the deer could have been exposed to the virus by people, other deer, other animals, or the environment.

Laboratory experiments have shown that deer—along with several other animals, including cats, nonhuman primates and deer mice—are susceptible to SARS-CoV-2 infection. For the most part infected animals don’t get very sick.

Researchers want to know which species are susceptible to the virus in part to better understand the potential for “spillback”—or the reverse of the natural spillover from animals to people that many scientists believe caused the pandemic. With spillback, infected people could spread the disease to other species and create a new reservoir for the virus. Transmission among animals could also lead to new variants. In experiments, researchers have shown that the virus begins to mutate quickly after spreading among just a handful of animals.

While it’s not known whether deer can spread the virus to people—the government researchers believe the risk is low—there have already been documented cases of farmed minks spreading the disease to workers.  Hundreds of people in the Netherlands were infected with mink-related variant viruses last year.

White-tailed deer are common in North America.

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View Comments

  • What a better way to get people to stop hunting, get our firearms, and turn us into tofu burger eating people.

  • Given the following, it would be extremely helpful to know the nature of the antibody tests done in this study:

    Each antibody test picks a specific part of the virus as their target molecule. In the case of SARS-CoV-2, most of the tests are focusing on the virus’ spike protein that it uses to invade cells. Some tests are binding the S1 region of the coronavirus spike protein (the spike protein has two subunits, S1 and S2), Jørgensen said. Others are binding a small part of S1, called the receptor-binding domain (RBD), which is the specific protein that latches onto the human ACE2 receptor to enter cells. The RBD may be the most specific part of the antibody for SARS-CoV-2, since other parts of the virus look more like other coronaviruses, Jørgensen said. Can antibody tests tell if you're immune to COVID-19? | Live Science

    Taxonomy browser (White-tailed deer coronavirus US/OH-WD470/1994) (nih.gov) This is not the SARS-CoV-2 virus but does have S1 protein which may or may not have the same RBD component as SARS-CoV-2. Likely according to the above it does not. So were the tests for S1 or RBD antibody?

    Aside from deer testing issues, testing in humans is fraught with many other difficulties.