Chinese researchers said Thursday that they had found a batch of new coronaviruses in bats, including one that is possibly the second closest, genetically, to the Covid-19 virus.
According to the researchers, their findings in a single, small region of Yunnan province, southwestern China, show how many coronaviruses are in bats and how many have the potential to spread to humans.
Weifeng Shi from the University of Shandong and colleagues collected samples from small forest-dwelling bats between May 2019 and November 2020. They tested urine and feces as well as took cotton swabs from the bat’s mouth.
“In total, we collected 24 new coronavirus genomes from various bat species, including four SARS-CoV-2-like coronaviruses,” the researchers wrote in a report published in the journal Cell.
One was very similar, genetically to the SARS-CoV-2 virus causing the current pandemic, they said – a viral sample called RpYN06 taken from a horseshoe bat species called Rhinolophus pusillus.
It would be the closest strain to SARS-CoV-2 with the exception of genetic differences in the tip protein, the bud-like structure that the virus uses when it attaches to cells, they said.
“Together with the SARS-CoV-2-related virus collected from Thailand in June 2020, these results clearly show that viruses closely related to SARS-CoV-2 continue to circulate in bat populations and may occur in some regions. with a relatively high frequency, ”they wrote.
Researchers are trying to find out where SARS-CoV-2 came from. Although a bat is a likely source, it is possible that the virus infected an intermediate animal. The SARS virus, which caused an outbreak in 2002-2004, was traced to an animal called a civet cat.
“Bats are well-known reservoir hosts for a variety of viruses that cause serious diseases in humans and have been linked to releases of Hendra virus, Marburg virus, Ebola virus and especially coronavirus. “Apart from bats and humans, coronavirus can infect a wide range of domestic and wild animals, including pigs, cattle, mice, cats, dogs, chickens, deer and hedgehogs,” they wrote.
Most of the samples came from species of horseshoe bats. In 2017, researchers sampling a cave in Yunnan found viruses very close genetically to the SARS virus in horseshoe bats.
Three of the samples described in Thursday’s report were also close to SARS genetically.
“Our study highlights the remarkable diversity of local-scale bat coronavirus, including close relatives of both SARS-CoV-2 and SARS-CoV,” they wrote. The bat species, the sampled ones, are common in Southeast Asia, including southwestern China, Vietnam, Laos, and elsewhere.
Although there is some controversy about the origin of the coronavirus pandemic, a report from the World Health Organization said the most likely source is an animal – probably a bat.
People hunt and eat bats, and bats can infect other animals that are also hunted and eaten by humans. Viruses can infect humans when they handle or slaughter animals.