Chinese scientists have traced the severe acute respiratory
syndrome (SARS) virus back to a similar virus found in the civet
cat and the raccoon dog, both animals found in the wild in China
and elsewhere.
Three strains of SARS-like virus isolated from samples of six palm
civets and a raccoon dog were similar to the human SARS virus, and
sequencing of their genes indicated the animal virus was the
precursor to the human form, said Zhuang Zhixiong, director of
Shenzhen Disease Control and Prevention Center.
Zhuang said a group of scientists from Shenzhen and neighboring
Hong Kong had searched for animals affected by SARS to determine
the relation between animal and human SARS viruses before locating
the possible source of human SARS virus.
During the research, they focused their attention on mammals,
including the palm civet, coypu, raccoon dog, cat, rabbit and three
other animals, said the director.
The gene sequencing showed 99 percent of the animal virus and human
SARS virus was homologous, or similar in structure.
The scientists also tested 10 dealers of wild animals for the SARS
antibody, and found five were positive, said the director.
The result indicated the SARS virus in wild animals might be able
to infect those in close contact with them.
The director said the findings provided clues for scientists to
determine the original sources of SARS virus and how it spread.
(Xinhua News Agency May 24, 2003)