Covid-19 spread among white-tailed deer in US causes concern over new variants

The coronavirus disease (Covid-19) pandemic has infected millions of people across the globe. In the two years since its emergence, the virus has mutated, grown stronger and led to waves of infection, which initially led to a high number of fatalities.

This was the reason why health experts across the world advised people to minimise physical contacts, and wear protective gears like face masks and face shields, and sanitise their hands and places they visit to protect themselves against the virus.

But now, a new development has worried the doctors and experts in the United States – the discovery of coronavirus in Iowa’s white-tailed deer. What makes it more dangerous, according to healthcare experts, is the fact that there are 30 million of these animals, and they usually come in contact with humans.

A report in New York Times said when the scientists sifted through frozen samples of the deer killed by hunters or cars in 2020, they found 60 per cent of them infected with the coronavirus.

“It was stunning,” Vivek Kapur, a microbiologist and infectious disease expert at the Pennsylvania State University, told NYT. His team has so far analysed samples from 4,000 dead deer and marked the location of each infected animal on a map. “It’s completely mad. It looks like it’s everywhere,” he said.

Adaptation in animals is one route by which new variants are likely to emerge. “This is a top concern right now for the United States,” Dr Casey Barton Behravesh, who directs the One Health Office at the Centers for Disease Control and Prevention (CDC) told the New York Times.

The US reported its first case of Covid-19 in a deer back in August last year. But this fresh discovery has renewed concerns about a new wave of infection believed to be transmitted from animals. The US Department of Agriculture had previously reported Covid-19 in animals including dogs, cats, tigers, lions, snow leopards, otters, gorillas, and minks.

The minks garnered much attention, leading to massive culling of the animals.

The scientists have always feared about the spread of the infection from animals to humans, but have sought more studies before arriving at any conclusion. In the latest case in Iowa, they say that those eating the cooked deer meat are at a lesser risk of contracting the Sars-CoV-2 virus, than those who come in contact with their faeces and droppings. Moreover, the virus can also get transmitted in lions which kill deer by biting into their trachea or over their nose and mouth.

Early research has suggested that cattle and pigs are at the lowest risk of getting the coronavirus, say scientists quoted by the New York Times. But inside the body of a deer, which shows very little symptoms, it can morph into a pathogen capable of infecting such livestock.

According to CDC, the risk of animals spreading Sars-CoV-2, the virus that causes Covid-19, to people is low. It further said that some coronaviruses that infect animals can be spread to people and then spread between people, but this is rare.

The CDC has advised people with suspected or confirmed Covid-19 to avoid coming in contact with animals, including pets, livestock and wildlife.

The Union health ministry in India has said many times that coronavirus spreads only through human-to-human transmission and not from animals. In a detailed note on coronavirus, uploaded on its website, the health ministry said that there is no evidence that a dog, cat or any pet can transmit Covid-19. It, however, asked people who handle raw meat, milk or animal organs to avoid contamination of uncooked foods and consuming raw or undercooked animal products.

After the discovery of coronavirus in Iowa deer, the USDA is collecting blood samples and nasal swabs from deer in more than two dozen states, reported NYT. The scientists, meanwhile, are advising keeping a close eye on the wildlife. They say if the virus is so prevalent in deer, which are relatively easy to sample, it could be silently spreading in other species too.

Experts like Dr Kapur said the only reason they found the virus in deer is because they thought to look.