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Now identified as likely origin of SARS; will bats be killed in China?
mongabay.com editorial comment
September 29, 2005


The likely source of the respiratory disease SARS is the horseshoe bat, a new study in the journal Science suggests. Researchers found a virus closely related to the SARS coronavirus in bats from three regions of China. The 2003 SARS outbreak killed 770 people and caused billions in economic damage.

Will bats be persecuted?

Conservationists and scientists are concerned that since bats have now been identified as the likely source of SARS that they will be killed by the masses.

Despite their potential harboring of SARS and Nipah virus, bats play a critical role in the health of ecosystems. Many plant species, including Kapok, eucalyptus, durian, mango, clove, banana, guava, avocado, breadfruit, ebony, mahogany, and cashew trees, depend exclusively on bats for pollination and seed dispersal.

Bats are the dominant pollinators of forests on remote Pacific islands. Since many plant species on such islands coevolved features to facilitate specific bat pollination, once bats are eliminated there are no other pollinators to fill the niche. Bats also play a crucial role in controlling insects. In several locations, municipal bat roosts have been proposed to reduce malaria-carrying mosquitos.

The blind persecution of bats would be a regretful mistake. Let's hope authorities use discretion with the disclosure of the bat-SARS link.

CSIRO press release announcing the Bat-SARS link
Bats identified as likely origin of SARS

Collaborative research involving scientists in Australia, China and the US concludes – in a paper published on 29 September in Sciencexpress, the special online edition of Science – that bats are highly likely to be the natural host of the virus responsible for severe acute respiratory syndrome (SARS).

Caused by a previously unrecorded coronavirus, SARS emerged in the southern China province of Guangdong in 2002. By July 2003 it had spread worldwide killing 774 people and infecting a further 8,000.

SARS research team leader at CSIRO Livestock Industries' Australian Animal Health Laboratory (AAHL) in Geelong, Dr Linfa Wang, says although earlier studies indicated a cat-sized mammal found throughout Asia - the civet - could be a natural host of SARS, subsequent studies have revealed no widespread infection in wild or farmed civets.

"Bats are known reservoir hosts of an increasing number of zoonotic viruses (viruses capable of infecting both animals and people), but they rarely display clinical signs of infection. It was these characteristics and the fact that bats are present in Asian food markets that led us to survey them," he says.

The study sampled more than 400 bats in their native habitat from four locations in China. Blood, faecal and respiratory swabs were collected and independently analysed at AAHL and the Chinese Academy of Sciences' Wuhan Institute of Virology.

"Among the six genera of bats surveyed, three species from the genus Rhinolophus (horseshoe bats) showed high antibody prevalence. More than 70 per cent of R. macrotis bats from Hubei had SARS coronavirus antibodies in their blood," says a research team member from the Queensland Department of Primary Industries and Fisheries, Dr Hume Field.

The serological findings were supported by genetic analysis of the faecal samples.

"The viruses detected from bats show greater genetic variation than those SARS coronaviruses which cause disease in humans and other animals. This variation suggest it's highly likely that the 2002/3 SARS outbreak originated from bats," Dr Wang says.

"Now we need to find out how these viruses 'jump' from bats to other animals and people. This is crucial if we are to manage the risk of future outbreaks," Dr Field says.

The Australian Biosecurity Cooperative Research Centre funded a collaborative CSIRO research project, enabling researchers to test for potential SARS virus infection in different animals.

Another research team, including Professor Yeun Kwok-Yung, microbiologist at the University of Hong Kong, published similar findings in the Proceedings of the National Academy of Sciences on 27 September.

The five institutions involved in this research were: Institute of Virology and Institute of Zoology, Chinese Academy of Science (China); AAHL; the Department of Primary Industries and Fisheries Queensland; and the Consortium for Conservation Medicine, New York (USA).




This article includes a modified press release from CSIRO. The original version is available at Bats identified as likely origin of SARS