Ever since severe acute respiratory syndrome was brought under control this summer, medical authorities have warned that another outbreak could occur in the fall. The world got its first fright last month with reports of occurrences in Singapore and Hong Kong. In fact, the Hong Kong case was not SARS; although the Singapore man has tested positive, his was apparently an isolated case. Nonetheless, SARS is likely to be back. And, even if SARS does not resurface, a similar disease will. The international medical community has been alerted to the new pathology of infectious disease. There is no excuse for not being ready for the next outbreak.

SARS emerged in southern China last November. It was first mistaken for a severe form of pneumonia, but testing later identified it as a new disease. Between November and May, SARS infected an estimated 8,500 people in 30 countries, killing more than 800. The disease alerted governments and citizens to the realities of an interconnected, globalized world. It highlighted the vulnerabilities of national medical systems and the havoc that could be wreaked by new threats -- both advertent and accidental. SARS underscored the necessity of cooperation and coordination to combat these new diseases -- and, in China's case, the utter failure of archaic operating procedures and assumptions about how to conduct the business of governing the nation.

Oddly, for all the attention that was devoted to SARS, there is still much that is unknown about the disease. We know that it is caused by a coronavirus, a member of a family of viruses that causes cold-like symptoms in people and a wide range of diseases in animals, but its origins are still shrouded in mystery. It was originally assumed that the disease jumped species, perhaps from pigs to humans in southern China. This summer, scientists in Hong Kong conducted genetic tests on animals and found a virus in both humans and animals that appears to be the culprit. It was found in the palm civit, a raccoon-like animal that is considered a delicacy in China. Many animals are kept and butchered in markets throughout the country. Beijing banned the sale of 52 of them in May as part of its war on SARS, but they are delicacies, which means they command a high price and tempt buyers and sellers to break the law.