Covid antibodies have been found in white-tailed deer: Scientists are concerned about hidden virus reservoirs in animals
Antibodies were found in 40 percent of the samples, indicating that white-tailed deer were exposed to SARS-CoV-2.
While humans face the brunt of the coronavirus pandemic, animals have not remained untouched by the viral infection. A new study on animals in the US shows that one-third of white-tailed deer in the north-eastern part of the country have developed antibodies against SARS-CoV-2, indicating they had been infected in one way or the other.
Researchers analysed the samples collected after the pandemic began in what could be the first detection of the virus in a wild animal population. Researchers targeted white-tailed deer, Odocoileus virginianus, for sero-surveillance based on evidence that these deer have receptors with a high affinity for SARS-CoV-2.
The study published in yet to be peer-reviewed preprint on bioRxiv states that antibodies were detected in 40 per cent of the samples suggesting that white-tailed deer have been exposed to SARS-CoV-2.
“It’s an intriguing observation but still needs to be interpreted with caution,” Nature quoted Aaron Irving, an infectious diseases researcher at Zhejiang University in Haining, China as saying.
A reservoir of virus
Previous laboratory experiments had shown that the deer can become infected with SARS-CoV-2 and transmit the virus to other deer. The findings are raising concerns over the possibility of animal populations harbouring the SARS CoV-2 virus as reservoirs, even after humans are vaccinated. Researchers fear that these reservoirs of viruses could allow Covid-19 to spread to other species and back to people.
Researchers collected 385 blood samples wildlife-surveillance between January and March 2021 of which 152 samples showed the presence of antibodies. These samples were collected from regions of Michigan, Pennsylvania, Illinois and New York.
“Given the percentage of samples in this study that had detectable antibodies, as well as the high numbers of white-tailed deer throughout the United States and their close contact with people, it is likely that deer in other states have also been exposed to the virus,” Nature quoted a spokesperson for the US Department of Agriculture (USDA) as saying.
Not a lone case of animal infection
The presence of antibodies in the white-tailed deer is not the lone case of an animal being infected by the deadly pathogen. Two rare Sumatran tigers at the zoo in the Indonesian capital are recovering after being infected with Covid-19.
Nine-year-old Tino became ill with shortness of breath, sneezing, and a runny nose on July 9, losing his appetite. Two days later, 12-year-old Hari was showing the same symptoms. The tigers were immediately treated with antibiotics, antihistamines, anti-inflammatory drugs and multivitamins. They were getting better after 10-12 days, and have now recovered under close observation at Jakarta’s Ragunan Zoo.
Meanwhile, in India, eight Asiatic lions at Hyderabad’s Nehru Zoological Park had tested positive for Covid-19 as well. This was the first time in India that transmission of the virus to animals through humans had been detected. However, the symptoms subsided after the lions were put on medication for almost two weeks. Analyses of the samples revealed that the infection was not caused by any variant of concern.
Researchers are now focusing on studying the likely reservoirs of these viruses in animals as they try to understand the source of the infection.