COVID-19 was first introduced to humans from animals and can infect many animals including those kept as pets. Professor Martin Michaelis and Dr Mark Wass of the School of Biosciences discuss the potential impact of COVID-19 on animals including our household friends:
‘SARS-CoV-2, the coronavirus that causes COVID-19 is a zoonotic virus, which means that it is a pathogen that has crossed the species barrier from animals to humans. It is not quite clear how this has happened, but evidence suggests that SARS-CoV-2 has originated from coronaviruses circulating in bats, from which it has been transmitted to humans, either directly or via one or more intermediate species such as the pangolin.
‘SARS-CoV-2 can infect many different animal species. Particularly prominent are the infections of minks in fur farms, in which the disease was transmitted from humans to minks and then back to humans. This established concerns of new ‘mink’ variants that may pose an enhanced risk due to potentially higher transmissibility, more severe disease, or being able to bypass existing immunity conferred by vaccines or previous infections. In the US, wild minks have been found to be infected with SARS-CoV-2 and undetected cases in farmed or wild minks may risk our efforts to fight the COVID-19 pandemic.
‘Given the high levels of COVID-19 spread in the human population, humans have actually now become a threat to many animals. African green monkeys, rhesus macaques, and cynomolgus macaques are susceptible to infection and based on receptors used by the virus to enter host cells, endangered primate species including gorillas, chimpanzees, and orangutans are anticipated to be at risk from COVID-19-infected humans.
‘Dogs can be infected with SARS-CoV-2 but do not seem to develop the disease or transmit the virus, though cats may be a greater concern. Domestic cats, tigers, lions, snow leopards, and a puma are known to have been infected. Domestic cats can transmit the current SARS-CoV-2 strains, albeit in a limited way. Ongoing cat-to-cat COVID-19 transmission chains seem unlikely with the current variants, but human-cat-human and occasionally human-cat-cat-human transmission chains seem feasible. Besides, cat exposure to COVID-19 may result in mutations that enable SARS-CoV-2 variants to spread sustainably in cats, so an argument can be made for including cats into our strategies for the control of COVID-19 spread.
‘Hamsters are another popular pet species that is known to be susceptible to COVID-19.
‘So, SARS-CoV-2 can infect many, though not all, animals including endangered species and domestic pets, which may be involved in COVID-19 spread. Every time a virus crosses a species barrier, new dangerous variants may emerge. Hence, the infection of domestic and wild animals may come back to haunt us via re-infections with more harmful variants.
‘Keeping the COVID-19 numbers low in the human population will protect other animal species and humans from the emergence of new virus variants.’