Suspected SARS case may have rat link ( 2004-01-05 07:42) (China Daily by Zhang Feng)
Rats may prove to be the missing link in a suspected case of SARS (severe
acute respiratory syndrome) first reported in Guangzhou, capital city of South
China's Guangdong Province.
A kitchen
worker hits a water rat on the head to stun it before it is killed for a
meal in a restaurent in the southern Chinese city of Guangzhou.
A mutated strain of the deadly virus was
diagnosed on a 32-year-old freelance television producer, making him the first
suspected SARS patient on the mainland since last May.
However, health officials and top experts reached by China Daily yesterday
cautioned that more laboratory tests must be done before any confirmation can be
made.
New details surfaced when local Guangzhou media reported the patient had set
traps for rats that had invaded his apartment before he showed SARS symptoms.
Laboratory tests have shown that some of the rats caught in his apartment also
tested positive for SARS.
However, this does not necessarily mean that the rats are the definitive
source of the new strain of coronavirus, Liu Qiyong, an expert on epidemics from
the Chinese Centre for Diseases Control and Prevention (CDC), said yesterday.
The result may have been caused by some other strain of coronavirus carried
by the rats, since there is a slight difference from the kind that caused the
SARS outbreak in human beings last spring, Liu said. In fact, other strains have
been found in rats, as well as in other animals long before the new case
emerged.
Liu and his colleagues have checked out more than 10 kinds of animals,
including masked palm civets and rats over the past several months trying to
identify the virus that has caused SARS. More work must be done to pinpoint one
particular strain as the one that jumped to human beings, Liu said.
Liu's remark was echoed by Mao Qun'an, spokesman for the Ministry of Health,
who told China Daily that scientists must do further research before they can
answer questions such as how SARS was passed to human beings from animals or
other sources.
Mao said Chinese experts generally tend to agree that samples from the
Guangzhou man with positive SARS result in lab tests are conclusive that he has
contracted SARS.
However, Mao and World Health Organization spokesman Roy Wadia both
emphasized that experts from WHO are re-examining the results submitted by their
Chinese counterparts, and their conclusion is expected to come out today or
tomorrow.
However, some WHO experts have cautioned that, without obvious SARS
connection like a wild animal or lab contamination, and without separating the
virus from the man's body, it is still too early to confirm the case. The
positive results are not enough of an indicator, they argue, because the man
could have been infected last spring but, due to internally developing antibody,
may not have shown any symptoms until now.
