GENEVA - The World Health Organization removed the last country - Taiwan - from its list of SARS-infected areas yesterday, ending an epidemic that in its three-month surge around the world infected thousands and shook economies from Asia to North America.
Taiwan was given a clean bill of health by the United Nations agency because its most recent victim was isolated 20 days earlier, twice the length of the disease's 10-day incubation period.
"The SARS outbreak has been contained worldwide," said WHO Director-General Gro Harlem Brundtland. She credited "unprecedented global collaboration" for overcoming a contagion that spread to 30 nations on five continents, sickening 8,439 people and killing 812.
But Brundtland warned that the world is not SARS-free. About 200 SARS patients remain under hospital quarantine. "It is possible that some SARS cases have slipped through the surveillance net," she said. "We know that one single case can spark a new outbreak."
The WHO believes that the virus is likely to flare up again this fall or winter, after the seasonal pattern of cold or flu viruses.
"A false [sense of] security could become our worst enemy," said David Heymann, director of the WHO's communicable diseases division, which coordinated the worldwide fight against SARS.
If SARS proves to have seasonal cycles, public health authorities could face formidable challenges distinguishing the new disease from more common ailments that also cause fever and influenza-like symptoms.
Brundtland, however, said the world is much better prepared if there is a next time.
Researchers are moving quickly to create a fast, reliable test to identify the disease in its early stages. And unlike the first outbreak of SARS, which was allowed to spread, in part, by the Chinese government's failure to report the disease as it first gained momentum, every nation is now aware of the potential cost of hiding an epidemic.
"There is no way to hide anymore," Brundtland said.
SARS - formally known as severe acute respiratory syndrome - originated in China's Guangdong province last fall, possibly passed to humans from a weasel-like animal known as a civet. The animal is considered a delicacy in parts of Asia.
With the likelihood of a new round of SARS infections in the fall, the WHO is hoping to build on the multinational cooperation created over the crisis to limit any future outbreak.
Health authorities and governments worldwide are painfully aware of what can happen if they are slow to react. Doctors are also more familiar with the symptoms of SARS, increasing chances that the disease could be caught early.
The WHO is focusing its attention on finding the probable reservoir of the SARS virus in animal populations and perhaps in apparently healthy or mildly ill people who still might spread the disease. The agency is also promoting the development of a global database to put the knowledge gained during the epidemic into the hands of SARS researchers and clinicians.
Charles Piller writes for the Los Angeles Times, a Tribune Publishing newspaper.