Dangers of human-to-animal transmission of COVID-19

Scientists are faced with a new problem related to the coronavirus: the risk of its transmission to wild animals. Veterinarian microbiologist Anna Fagre from Colorado State University in the new article The Wired.

Usually her job is to search for viruses in the wild, which can potentially be transmitted to humans. Now she and her colleagues have the opposite task: to find a way to prevent the transmission of COVID-19 to wild animals.

And this threat is serious: in recent years, even less common diseases have passed from humans to wild animals. Ebola passed from humans to monkeys in the early 2000s with catastrophic consequences, seals and sea lions were infected with swine flu in 2009-2011. Other respiratory viruses have learned to infect mountain gorillas, a subspecies that have already been given protected status.

If Sars-CoV-2 can actually move to a new animal population, it could prolong the pandemic indefinitely, provided that the virus will periodically move between animals and humans. In addition, it will help the virus mutate further, potentially leading to the creation of new strains that are more infectious, deadly and resistant to existing vaccines.

Over the past month, a series of new experiments in laboratories at Colorado State University have demonstrated how quickly Sars-CoV-2 can mutate into a new species. When Fagre's colleagues infected cats and dogs with the virus, they found that its spike protein had mutated after being transmitted by just three different animals.

In a similar experiment with deer mice, mutations appeared in just two transmissions. Fagre notes: “Almost the entire population of the virus acquired this new mutation in just a few cycles. These coronaviruses are very well transmitted between species. We've seen it before with Sars and Mers, and now with Sars-CoV-2. " If such mutations occur in uncontrolled conditions in the wild, the consequences for both animals and humans can be catastrophic.

Although pets are at greatest risk of transmission because they are in constant contact with humans, it is relatively not dangerous, because they, as a rule, are located within the same house and, having become infected from the owners, will not be able to transmit him further.

Scientists are most concerned about wild animals, which could potentially transmit the virus uncontrollably, which in turn will be constantly changing. If then he again gets to a person, there is no guarantee that the immunity will work.