NEW YORK, NEW YORK - E-Wire
NEW YORK, NEW YORK, Sep. 29 -/E-Wire/-- Scientists at the Consortium for Conservation Medicine (CCM), based at Wildlife Trust, in collaboration with Chinese and Australian colleagues, have discovered that SARS originated in bats, not civets, as once believed.
Dr. Peter Daszak, Executive Director of the CCM and Dr. Jonathan Epstein, Senior Research Scientist and veterinary epidemiologist at the CCM, are contributing authors on the definitive paper, "Bats Are Natural Reservoirs of SARS-like Coronaviruses," published on Thursday, September 29 in Science Express, the online page of Science magazine. The paper also will be published in Science at a later date.
The definitive paper identifies Chinese horseshoe bats as the reservoir for SARS, something other research has only suggested. The team proved it by a far larger sampling than has been completed previously, from numerous sites in Mainland China, including the site where SARS first emerged.
"This important research finding is a major breakthrough for the new field of Conservation Medicine, which is a new discipline that brings together health professionals and wildlife scientists to examine links between human, ecosystem, and animal health," according to Dr. Mary Pearl, President of Wildlife Trust and co-founder of the Consortium, which is based at Wildlife Trust's offices in New York.
"We can now conclusively say that we know the origin of SARS, and like most other emerging diseases (including HIV/AIDS, monkeypox, West Nile virus and avian flu), the virus was transmitted from animals to people," Dr. Peter Daszak explains. "These diseases emerge because of human activities such as wildlife trade and global travel. Anytime you bring multiple species of animals together at high density and mix them with humans, you're setting the stage for pathogens to jump between species and for an outbreak to occur."
Donald S. Burke, Professor of International Health at the Johns Hopkins Bloomberg School of Public Health, says, "Finding the ultimate source of the SARS coronavirus is the epidemiological equivalent of discovering the source of the Nile. The virus circulates in bats, spills into civets, and emerges into humans. Now it should be possible to interrupt that flow."
Dr. Jonathan Epstein led the first collaborative expedition to China in March 2004, to survey bats for zoonotic pathogens, including the SARS coronavirus and Nipah virus. The team collected samples from bats caught in the wild from several regions as well as captive bats from live markets in Guangdong, where SARS originally emerged. Samples were sent to virology labs at the CSIRO, Australia and the Wuhan Institute of Virology in China, to be tested for SARS-CoV and other pathogens.
Dr. Epstein explains, "It's crucial to identify the reservoirs of these emerging pathogens so that we can understand how they emerged, and predict and prevent future outbreaks. Civets were originally thought to be the origin of SARS but most researchers realized that the true wildlife reservoir remained a mystery. Our role was to visit the outbreak site and other areas in China and search for this reservoir. We targeted bats because they are the source of other lethal pathogens that have recently emerged, and are part of the wildlife trade throughout Asia."
Dr. Daszak coordinated the CCM's role in the international collaboration. The research team tested more than 400 bats, representing nine species, six genera and three families, from four locations in China (Guangdong, Guangxi, Hubei and Tianjin) to which the bats are native. The study was completed between March and December, 2004. RNA sequence data, phylogeny and serological evidence showed that a coronavirus (named "SARS-like-coronavirus Rp3", or SL-CoV Rp3, by the team) was found in three species of horseshoe bats (Rhinolophus species) and is the progenitor of both the civet and human SARS CoV.
Dr. Pearl emphasizes the importance of understanding the ecology of emerging diseases, rather than simply blaming wildlife for spreading disease. "Wildlife populations can act as buffers against the spread of disease as well as sources for its emergence. Through providing a better understanding of how pathogens move among species, the field of Conservation Medicine gives us the tools we need to maintain healthy ecosystems that protect people and wildlife."