NEW YORK (NewsNation Now) — Scientists say they are finding more animals infected with COVID-19.

White-tailed deer across a wide area, from the Midwest to the Northeast, have been found with the virus. Now the questions are how did they get it, and can they give it to us?

There is no evidence humans can get COVID-19 from deer, but scientists say many of the animals they tested have COVID-19 antibodies — meaning they somehow contracted the virus.

There are more than 30 million deer in the U.S. and many live very close to humans.

“When we conducted this study, it was an exploratory study. It was a first look at whether deer in the wild were exposed to the virus,” said USDA National Wildlife Research Center Dr. Thomas DeLiberto.

Between January and March, DeLiberto’s team from the USA collected 385 samples from deer in Pennsylvania, Michigan, Illinois, and New York, and tested them for antibodies against SARS-CoV-2. Forty percent of them came back positive.

“They had antibodies to the virus, which suggests that at some time in the past they had been exposed and infected by the SARS COV-2 virus,” said DeLiberto.

It’s unclear whether the deer caught the virus from humans, other animals, or environmental sources. The direct risk to humans is probably low, but the researchers say deer can carry the virus with no sign of being ill and they can shed the virus, too.

It wouldn’t be the first time deer picked up a virus that also affects humans. It’s happened with West Nile and hepatitis E.

With hunting season around the corner, there is cause for concern, but not much, according to experts.

“There’s no evidence that hunters can get COVID-19 from deer,” said DeLiberto.

Another concern the scientists have is COVID-19 entering new animal hosts could give it more chances to mutate into new variants.

It’s another factor, they say, that adds to the need to vaccinate more humans.