That’s a reasonable theory: other bat coronaviruses have jumped to humans the same way. In fact, it was the origin of SARS, a similar coronavirus that panicked the world in 2003 when it spread out of southern China and sickened 8,000 people. With SARS, researchers tested caged market animals and quickly found a nearly identical virus in Himalayan palm civet cats and raccoon dogs, which are also eaten locally.
This time, though, the intermediate-host hypothesis has one big problem. More than a year after covid-19 began, no food animal has been identified as a reservoir for the pandemic virus. That’s despite efforts by China to test tens of thousands of animals, including pigs, goats, and geese, according to Liang Wannian, who leads the Chinese side of the research team. No one has found a “direct progenitor” of the virus, he says, and therefore the pandemic “remains an unsolved mystery.”
Author(s): Antonio Regalado
Publication Date: 16 March 2021
Publication Site: MIT Technology Review