The Covid-19 pandemic has put a focus on zoonoses or zoonotic diseases – infections caused by pathogens that have jumped from animals to hu...
The Covid-19 pandemic has put a focus on zoonoses or zoonotic diseases – infections caused by pathogens that have jumped from animals to human beings – as well as on the need to protect the intricate webs of nature.
Bats and pangolins are the two most likely sources of the novel coronavirus, before it was established as SARS-CoV-2 in humans. In China, both are hunted for their meat and traded illegally for their body parts. The most likely source of transmission to humans are believed to be Southern China’s “wet markets”, where farmed and occasionally illegally captured wild animals are sold.
It is important to understand that many coronaviruses occur naturally in animals. These do not normally jump from one animal to another or from animals to humans. For instance, two closely-related species of novel bat coronaviruses – BatCoV RaTG13 and RmYN02, which were discovered in 2019 in horseshoe bats – are about 96% similar in their whole genome sequence to the human SARS-CoV-2. This is still much less than the similarity between chimpanzees and us.
Likewise, a pangolin coronavirus, Pangolin-CoV, has been found to have even less genetic similarity to SARS-CoV-2, at around 91%.
Wet markets bring such species, which would not naturally occur, into...
