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Scientists: Origin of Sars linked to bats from remote cave in Yunnan

Study sheds new light on origin of Sars

BEIJING: Chinese scientists believe they may have found the origin of the deadly severe acute respiratory syndrome (Sars) virus in a remote cave in Yunnan province, where they identified a population of horseshoe bats that harbour virus strains with all the genetic building blocks.

The strain could easily have arisen from such bats, according to research published in PLoS Pathogens on Nov 30. Scientists also warned that ingredients are in place for a similar disease to emerge again.

Researchers Shi Zhengli and Cui Jie from the Wuhan Institute of Virology in Hubei province led the team, sampling thousands of wild horseshoe bats from nine provinces.

In one cave in Yunnan province, the research team found that the strains of coronavirus looked similar to human versions of Sars. It took five years for researchers to monitor the bats living in the cave.

Sars emerged in South China in 2002 and rapidly led to a global pandemic, killing almost 800 people worldwide.

The culprit was identified as a strain of coronavirus, and genetically similar viruses were found in masked palm civets that are sold in animal markets in Guangdong province.

Later, a large number of Sars-related coronaviruses were found in horseshoe bats.

Scientists believe that the strain probably originated in the bats, and later passed through civets before reaching humans.

Ms Shi told Hubei Daily that wild animals carry various viruses but spreading across species rarely happens.

In an interview with Nature Magazine, virologist Tu Changchun, who directs the OIE Reference Laboratory for Rabies in Changchun, said the results are only 99 per cent persuasive.

He said he would like to see scientists demonstrate in the lab that the human Sars strain can jump from a species to another. He also questioned how a virus from bats in Yunnan could travel about 1,000km to Guangdong, without causing any suspected cases in Yunnan.

The magazine said the scientists also conducted research on other bat populations and have isolated about 300 bat coronavirus sequences. They will continue to monitor the virus' evolution. - ASIA NEWS NETWORK

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