The World Health Organization is recommending that airline passengers from areas with deadly pneumonia outbreaks be screened.
The World Health Organization late Thursday recommended that airlines and governments in Hong Kong, mainland China, Toronto, Canada, and Singapore screen departing passengers for signs of Severe Acute Respiratory Syndrome.
The stricter advisory replaces one that warned travelers to be aware of the high fever and flu-like symptoms associated with SARS. There are fears that the outbreaks in Hong Kong, mainland China, Toronto and Singapore have not yet been adequately contained. The disease often leads to a potentially lethal form of pneumonia.
The most recent alert, posted on the WHO Web site, warns officials in the affected areas to advise travelers who may be ill, or may have been exposed to SARS, to postpone their trips. Medical workers who have treated SARS patients, and relatives and close associates of patients are considered to be at a high risk of developing the disease.
While WHO says the virus that apparently causes SARS is transmitted only through close contact, the agency links the disease's spread in some cases to people traveling together on planes.
The WHO advisory does not recommend disrupting the world travel system, nor outright travel restrictions. Even without such recommendations, airlines and governments can impose travel restrictions when they deem fit.
The stricter advisory came just hours after Hong Kong, which is one of the worst hit cities, said it would quarantine more than a thousand residents at high risk of developing the disease and closed all schools. Singapore and Taiwan have taken similar actions.
An estimated 1,400 people have been afflicted with SARS worldwide. Hong Kong and southern China account for two-thirds of the cases. The disease may have first appeared in southern China late last year, but it has spread rapidly across borders in the past month.
About 50 SARS victims have died worldwide, 11 of them in Hong Kong.
Hospitals in the city, however, are finding success at treating SARS patients with anti-viral drugs and steroids. They warn, however, that delaying treatment reduces the chance of a full recovery.
The WHO on Thursday recognized findings made by Hong Kong researchers that a virus similar to the one that causes the common cold is responsible for SARS. The U.N. agency confirms that many of the 11 laboratories participating in the race to identify and isolate the virus have made similar discoveries.
Malik Peiris, a microbiologist at Hong Kong University, says the virus might have jumped from animals to infect humans. "It seems unlike any of the human or animal viruses that have been described up until now. It falls into a group of viruses called coronavirus. Of course, we will be studying different animal species to see if these animals have antibodies."
He says his lab has also developed a simple diagnostic test that can determine if a patient has SARS in a matter of hours.