Volume 302, Number 5643, Issue of 10 October 2003
©2003 by The American Association for the Advancement of Science.

COMMENTARY An Animal Link in SARS The coronavirus SCoV that causes severe acute respiratory syndrome (SARS) has been thought to be an animal virus that recently crossed over to humans. Early cases of SARS occurred in Guangdong Province, China, among restaurant workers exposed to wild animals that are served as exotic foods. Guan et al . (p. 276 ; see the 5 September news story by Normile ) tested for SCoV in animals at a retail market in Shenzhen. Civet cats, a raccoon dog, and a ferret badger showed evidence of infection with a coronavirus similar to the virus that causes SARS in humans; the human isolates show a 29-nucleotide deletion compared with the animal isolates. It is unclear whether these animals are the natural reservoir of the virus or are intermediate species in transmission.

Science, Vol. 302, Issue 5643, 276-278, October 10, 2003

 
1087139v1
Isolation and Characterization of Viruses Related to the SARS Coronavirus from Animals in Southern China
Y. Guan, 1B. J. Zheng, 1*Y. Q. He, 2X. L. Liu, 2Z. X. Zhuang, 2C. L. Cheung, 1S. W. Luo, 1P. H. Li, 1L. J. Zhang, 1Y. J. Guan, 1K. M. Butt, 1K. L. Wong, 1K. W. Chan, 3W. Lim, 4K. F. Shortridge, 1K. Y. Yuen, 1J. S. M. Peiris, 1L. L. M. Poon 1

A novel coronavirus (SCoV) is the etiological agent of severe acute respiratory syndrome (SARS). SCoV-like viruses were isolated from Himalayan palm civets found in a live-animal market in Guangdong, China. Evidence of virus infection was also detected in other animals (including a raccoon dog, Nyctereutes procyonoides )and in humans working at the same market. All the animal isolates retain a 29-nucleotide sequence that is not found in most human isolates. The detection of SCoV-like viruses in small, live wild mammals in a retail market indicates a route of interspecies transmission, although the natural reservoir is not known.

1Department of Microbiology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong Special Administrative Region (S.A.R.), of the People's Republic of China (China).
2Center for Disease Control and Prevention, Shenzhen, Guangdong Province, China.
3Department of Pathology, The University of Hong Kong, University Pathology Building, Queen Mary Hospital, Hong Kong S.A.R., China.
4Government Virus Unit, Department of Health, Hong Kong S.A.R., China. *These authors contributed equally to this work.
To whom correspondence should be addressed. E-mail: yguan@hkucc.hku.hk

Severe acute respiratory syndrome (SARS) recently emerged as a human disease associated with pneumonia ( 1). This disease was first recognized in Guangdong Province, China, in November 2002. Subsequent to its introduction to Hong Kong in mid-February 2003, the virus spread to more than 30 countries and caused disease in more than 7900 patients across five continents ( 2). A novel coronavirus (SCoV) was identified as the etiological agent of SARS ( 3,4), and the virus causes a similar disease in cynomolgous macaques ( 5). Human SCoV appears to be an animal virus that crossed to humans relatively recently. Thus, identifying animals carrying the virus is of major scientific interest and public health importance. This prompted us to examine a range of domestic and wild mammals in Guangdong Province.
Because the early cases of SARS in Guangdong reportedly occurred in restaurant workers handling wild mammals as exotic food ( 6), our attention focused on wild animals recently captured and marketed for culinary purposes. We investigated a live-animal retail market in Shenzhen. Animals were held, one per cage, in small wire cages. The animals sampled included seven wild, and one domestic, animal species ( Table 1 ). They originated from different regions of southern China and had been kept in separate storehouses before arrival to the market. The animals remained in the markets for a variable period of time, and each stall holder had only a few animals of a given species. Animals from different stalls within the market were sampled. Nasal and fecal samples were collected with swabs and stored in medium 199 with bovine serum albumin and antibiotics. Where possible, blood samples were collected for serology. Before sampling, all animals were examined by a veterinary surgeon and confirmed to be free of overt disease. Serum samples were also obtained, after informed consent, from traders in animals ( n= 35) and vegetables ( n= 20) within the market. Sera ( n= 60) submitted for routine laboratory tests from patients hospitalized for nonrespiratory disease in Guangdong were made anonymous and used for comparison.