October 4, 2005

Bats passed SARS virus to civet cats – Chinese expert

HONG KONG (Reuters) - A species of bats in China might have
been the source of the SARS epidemic in 2003, a Chinese health
expert said on Tuesday, adding that the creatures probably
passed it to civet cats, which then passed it to humans.

Researchers in Hong Kong and China said last month that the
horseshoe bat - a delicacy in southern Chinese cuisine and
whose faeces are used in traditional Chinese medicine - was a
natural host of SARS-like viruses, meaning it could carry the
bugs but not fall ill.

Zhong Nanshan, China's leading SARS expert, said these bats
were stored in cages while waiting for buyers in wholesale
markets in southern Guangdong province and may have easily
passed on viruses to other species.

SARS, or Severe Acute Respiratory Syndrome, began spreading
in Guangdong in late 2002 and among its earliest victims was a
chef who handled civet cats. There has however been no
documented case of humans contracting SARS directly from
horseshoe bats.

Hong Kong scientists have said the SARS virus jumped from
civet cat to humans and quickly developed the ability to pass
from person to person. The disease spread to about 30 countries
in 2003 via air travel, killing some 800 people in all.

Zhong said civet cats farmed in other Chinese provinces
such as central Hubei and Hunan and southern Guangxi were not
found to carry the virus. But once they got to markets in
Guangdong, up to 78 percent of them were found to be hosting
the virus.

"So how did the civet cats get SARS? The view is horseshoe
bats are a very important reservoir for SARS," Zhong said.

"Could it be that in the wild animal markets they were kept
close to civet cats and then passed the virus to them?

"Guangdong's wild animal markets are a very important
transmission ground for SARS," Zhong said.

He also described civets as playing the role of an
"amplification tool" in the SARS epidemic. Once they contracted
it, they spread it among themselves like wildfire.

Researchers have however not been able to determine how the
bats were originally infected.

SARS is caused by a virus which belongs to the family of
coronaviruses. Coronaviruses are common in people and animals
and usually cause nothing more serious than a simple cold. But
the SARS virus proved to be very deadly, and had a mortality
rate of 10 percent in 2003.