Bats From A Single Cave In China Have All The Building Blocks Of A SARS Epidemic

Bats from a single cave in China have all the building blocks of a SARS epidemic

When it struck, the contagion spread fiercely. The deadly severe acute respiratory syndrome (SARS) outbreak in South China in 2002 infected thousands, and ultimately killed nearly 800 people.

But where did this lethal strain come from? We may now have our answer, with a study showing bats living in a single cave in China possess all the building blocks of the deadly SARS coronavirus – and potentially the means to create a new one.

Researchers from the Chinese Academy of Sciences spent five years analysing SARS viruses found in multiple species of horseshoe bats nesting in a cave in China’s Yunnan Province.

In all, the team identified 11 new strains of SARS virus carried by the bats, and a genomic analysis of these – along with strains from the same cave identified in previous research – revealed something interesting.

Previous research had suggested bat viruses could have been responsible for SARS, but scientists had never uncovered evidence of a direct ancestor to the human-infecting coronavirus in bat strains.

In the new research, that held true again – none of the viruses from the cave by themselves displayed the genetic traits of the SARS coronavirus that spread to humans, infecting more than 8,000 people during the 2002-2003 emergency.

But together, it was a different story. In this one cave, there were enough genetic ingredients among the strains to build the virus that kills humans.

“Importantly, all of the building blocks of SARS-CoV genome, including the highly variable S gene, ORF8 and ORF3, could be found in the genomes of different SARSr-CoV strains from this single location,” the researchers explain in their paper.

Hypothetically speaking, the team suggests it’s possible – even probable – that if the right strains mixed with one another in the cave, you’d end up with the direct ancestor of a virus that can infect and kill people.

The findings are reported in PLOS Pathogens.