Hundreds of species, including critically endangered apes, potentially at risk from COVID-19
More than 400 different species of vertebrates, including birds, fish, amphibians, reptiles and mammals, could potentially contract the virus that causes COVID-19, researchers at the University of California, Davis have found.
The team used genomic analysis to compare the main cellular receptor for the virus in humans – angiotensinconverting enzyme-2, or AC'2 – in 410 different species of vertebrates. AC'2 is found on many different types of cells and tissues, including cells lining the nose, mouth and lungs. In humans, 25 amino acids that make up AC'2 are involved in the mechanism by which the virus binds to and gains entry into cells. The researchers therefore wanted to investigate any similarities in animals.
“Animals with all 25 amino acid residues matching the human protein are predicted to be at the highest risk for contracting SARS-CoV-2 via AC'2,” said postdoctoral research assistant Dr Joana Damas. “The risk is predicted to decrease the more the species’ AC'2 binding residues differ from humans.”
About 40 per cent of the species potentially susceptible to SARS-CoV-2 are classified as ‘threatened’ by the International Union for Conservation of Nature and may be especially vulnerable to human-to-animal transmission. This includes several critically endangered primate species, such as the Western lowland gorilla, Sumatran orangutan and northern white-cheeked gibbon, that are predicted to be at a very high risk of infection by SARS-CoV-2 via their AC'2 receptors. Other animals flagged as high risk include marine mammals such as grey whales and bottlenose dolphins, as well as Chinese hamsters. Domestic animals such as cats, cattle and sheep were found to have a medium risk, and dogs, horses and pigs were found to have low risk for AC'2 binding.
“The data provide an important starting point for identifying vulnerable and threatened animal populations at risk of SARS-CoV-2 infection,” said lead author Prof Harris Lewin. “We hope it inspires practices that protect both animal and human health during the pandemic.”
The researchers note that the risks are based on computational results and the actual risks can only be confirmed through further experiments. Nevertheless, the findings should help scientists to zero in on which species might have served as an intermediate host in the wild and assist efforts to control a future outbreak of SARS-CoV-2 infection in human and animal populations, they say.