oh deer covid

November 3, 2021

Oh Deer …

New research shows the virus that causes COVID-19 has some familiar
four-legged hosts.
Why the pandemic in a deer population has scientists raising a warning flag.

The Backstory

  • Penn State researchers teamed up with Iowa State University and the Iowa Dept. of Natural Resources (which monitors deer in Iowa for disease).
  • Veterinary microbiologists examined the lymph nodes of dead deer (either hunted or killed in other ways, i.e. by a car).
  • From April 2020 – Jan. 2021, ~ 33% of deer tested positive for SARS-CoV-2; in a more condensed timeline (Nov. 2020 – Jan. 2021), more than 80% tested positive.
  • How did they get infected? No one knows.

“We were dumbfounded.”

One of the lead authors of the study, Dr. Suresh Kuchipudi of Penn State, says that evidence of active COVID-19 infections in deer showed up all over the state of Iowa. Confirming deer with *active* infections makes the research different from previous research, such as recent work by the USDA earlier this year that showed 40% of deer surveyed across four states had confirmed exposure to SARS-CoV-2. Dr. Kuchipudi says of his findings, “There is no reason to believe that the same thing isn’t happening in other states where deer are present.”

"To date, there have been no cases of contracting COVID-19 from eating food, including hunted wild meat."

Iowa Dept. of Natural Resources to the Des Moines Register. The genetic sequence of the strain found in the deer suggests they had the same or similar strains as humans at the time. As human infection rose in Iowa late last year, it also did in deer.

Why It Matters

“The … SARS-CoV-2 transmission in deer has important implications for the ecology and long-term persistence, as well as the potential for spillover to other animals and spillback into humans.”

Researchers question how the SARS-CoV-2 virus could mutate in another host, such as deer, and then be transmitted to humans. Health officials want to decrease the likelihood of variants and slow the spread of the virus; this revelation raises concerns about the future.

This study is still in preprint – meaning it’s not yet peer-reviewed before publication, which is an important research standard. Other animals, such as gorillas, tigers, house cats and dogs, have tested positive for COVID-19 – some of them with symptoms. We do not know if the deer were symptomatic or are simply “carriers” of this virus.

Deer in Iowa appear to be catching COVID-19 from humans. Could it happen in other states? (USA Today)

Widespread Coronavirus Infection Found in Iowa Deer, New Study Says (New York Times)

A third of white-tailed deer tested in a survey were exposed to the coronavirus (New York Times)

SARS-CoV-2 exposure in wild white-tailed deer (USDA study)

by Jenna Lee,