According to the New York Times reported on the 2nd, a new study of hundreds of white-tailed deer infected with the new coronavirus in Iowa found that these animals may be infected with the virus from humans, and then quickly infect each other.
White-tailed deer Image source: foreign media
The study revealed that from April 2020 to January 2021, as many as 80 percent of white-tailed deer in the state had been infected. Scientists say the findings create more worrying complications about the spread of the coronavirus, though they can't be sure how deer got the virus from humans and there's no evidence that deer ever spread the virus to humans.
Researchers and outside experts describe the study's findings as a troubling development in the pandemic process. The widespread spread of COVID-19 among the most prevalent animal species in North America could make eradication of these pathogens more difficult, especially as these animals could become repositories of mutated viruses that could eventually transmit the mutated viruses across species to humans again.
The study has not yet been published in a peer-reviewed scientific journal, but researchers at Pennsylvania State University and wildlife officials in Iowa found the results very disturbing, and they cautioned deer hunters and others exposed to deer to take precautions to avoid infection.
White-tailed deer Image source: People's Vision
Earlier this year, the U.S. Department of Agriculture tested 385 white-tailed deer blood samples collected in Michigan, Pennsylvania, Illinois, and New York from January to March 2021 and found that 40 percent of the samples detected antibodies related to the new crown virus, but the deer surveyed showed no signs of disease.
The researchers found that 3 of the samples collected in early 2020 detected relevant antibodies, and 1 of the samples collected in 2019 detected relevant antibodies. Taken in 2020 and 2021 samples combined, the proportion of white-tailed deer serum samples detecting covid-19-related antibodies in the northeast of the United States is one-third. A USDA spokesperson said that from the test results of the sample and the presence of a large number of white-tailed deer in the United States and their contact with people, white-tailed deer in other states may also be infected with the new crown virus.
The New York Times noted that some previous studies have hinted at the possibility of virus transmission from humans to deer, as many other animals in addition to white-tailed deer may also be infected with the new crown virus. These animals include ferrets and primates that were deliberately infected in laboratory experiments, zoo animals that contracted the virus from keepers, and captive minks that came into contact with farm workers.
White-tailed deer Source: Visual China
If the virus is endemic in wild animals like deer, over time, it is possible to evolve a more capable virus, and then a new strain infects humans that may be able to evade existing vaccines.
"If deer can spread the virus to humans, it will be a turning point." Tony Goldberg, a veterinarian at the University of Wisconsin-Madison, said. He studies the evolution of the spread of infectious diseases between animals and humans, and "it is very rare and unfortunate that wild animals become reservoirs of viruses after being infected with viruses from humans. ”
However, how the new crown virus is transmitted from humans to deer is not yet fully understood. Iowa wildlife veterinarian Rachel Ruden, one of the study's authors, said there are plenty of opportunities for transmission given that the state has 445,000 deer scattered in the wild.
The virus spreads when people feed deer in their backyards, drink water from their sewers, or lick tobacco left behind by infected hunters. "Maybe it doesn't take much virus volume to get infected," she said. But in any case, all of this is a notable example of the fact that we and the deer are in the midst of this pandemic. ”
The study raises questions that many scientists will be keen to study, including whether other wild animals will also carry the virus, especially rodents like rats that live closer to humans. The more species capable of carrying the virus, the more likely it is that new viruses will evolve that threaten human health.
(Editor: zlq)