Molecular Advances in Severe Acute Respiratory Syndrome-associated Coronavirus (SARS-CoV)

Chow, Ken Yan Ching; Hon, Chung Chau; Hui, Raymond Kin Hi; Wong, Raymond Tsz Yeung; Yip, Chi Wai; Zeng, Fanya; Leung, Frederick Chi Ching

The collaborative efforts of the global scientific community have provided invaluable insights into the molecular biology of the SARS-CoV. The development of a rapid and accurate method of diagnosis based on the molecular findings has helped to identify SARS patients at an early stage of the disease, thereby providing valuable information for national authorities to monitor the spread of the disease and take effective quarantine measures, and contributing to the understanding of the clinical presentations of the syndrome. The elucidation of the molecular biology of the SARS-CoV has provided a foundation for vaccine design and narrowed down the targets for large-scale high throughput drug screening program for anti-viral therapy. These advances helped the global community to contain the spread of SARS within four months since its first identification. However, much remains to be discovered about this novel coronavirus, and it may yet pose a serious threat. Unlike other recently identified viral diseases like Ebola and West Nile virus, it seems the transmission of SARS-CoV does not need a visible vector for spreading, and that a tiny, invisible, respiratory droplet is sufficient to infect another person (117 ) . The nearly undetectable symptom presented by the recently confirmed SARS case in Singapore suggests that the virus may continue to circulate undetectably (65 ) . The possibility that common domestic animals are also a virus reservoir for SARS further complicates the struggle to contain and ultimately eradicate this disease. In these aspects, sensitive, accurate and rapid diagnosis plays an extremely important role in limiting the disease spread, especially in the developing world and densely populated countries. Luckily, the aggressive quarantine measures imposed by the WHO proved to be effective in containing the outbreak, and the experience gained in the last SARS outbreak has prepared us to face another outbreak with some confidence. Nevertheless, nobody can predict exactly when an effective vaccine or anti-viral drug will be developed. All that can be said is that, based on our growing knowledge of the molecular epidemiology and evolution of the virus, the successful development of countermeasures to SARS is very possible.