Bats carry Sars-related virus
2005-09-30 13:00
Washington - Bats have been found to be natural hosts of so-called corona viruses closely related to those responsible for deadly outbreaks of Sars among humans, according to a study published this week.
Severe Acute Respiratory Syndrome (Sars) triggered a global health crisis after emerging in China's southern Guangdong province in November 2002, causing nearly 800 deaths worldwide, including 349 in China.
Scientists are vying to unravel the origins of its etiological agent, the Sars corona virus (Sars -CoV), which sparks the full-blown Sars virus.
A team of international researchers work have found that bats
are a natural host of these corona viruses. Their findings were published in the journal Science on Wednesday.
The researchers hope the finding will give them new insights into Sars and its potentially lethal origins.
The viruses, termed Sars-like corona viruses (SL-CoV), display greater genetic variations than Sars-CoV isolated from humans or some carnivorous mammals, according to the team's findings.
The team includes researchers in China, Australia and the United States.
The virus responsible for the Sars outbreak
The human and mammal isolates of SARS-CoV "nestle phylogenetically within the spectrum of SL-CoVs," suggesting that the virus responsible for the Sars outbreak was a member of the corona virus group, the study said.
"Without knowledge of the reservoir host distribution and transmission routes of Sars -CoV, it will be difficult to prevent and control future outbreaks of Sars," the study's authors noted.
They said that bats "may be persistently infected with many viruses but rarely display clinical symptoms."
The researchers said such characteristics and the increasing presence of bats and bat products in food and traditional medicine markets in southern China and elsewhere in Asia led them to focus on bats the search for the origin of the Sars virus.
The study was conducted between March and December 2004, and involved 408 bats of nine different species.
Researchers from the Institute of Zoology of Chinese Academy of Sciences in Beijing, China, the Australian Animal Health Laboratory in Geelong, Australia, and The Consortium for Conservation Medicine in New York, among other centres, supported the research.