GENEVA -- Scientists said yesterday that they believed they have developed a test for diagnosing the mysterious flu-like illness that has sickened hundreds in Asia -- a crucial step in slowing the disease's spread.
Officials with the World Health Organization said the test still needed further experimenting, but if successful, it should be in the hands of doctors in a few weeks and available in key laboratories in a few days.
"We're all very pleased. It is crucial and it's another step on the way, but there's a lot that still has to be done," said Dr. David Heymann, WHO's communicable diseases chief.
A diagnostic test would make it possible for doctors to quickly weed out and isolate patients with the new disease, called severe acute respiratory syndrome, or SARS. It has made 350 people around the world ill and killed 10 people in the past three weeks, according to WHO figures.
Nine more people in the United States are suspected of having the mysterious flu-like illness that has sickened hundreds in Asia, the federal government said yesterday.
A total of 22 people in this country now are suspected of being sickened by SARS, said Dr. Julie Gerberding, director of the Centers of Disease Control and Prevention. The suspected cases involve people who recently have been to Asia and developed fever and respiratory problems.
The CDC Web site listed six cases in California; three in Hawaii; two each in the states of North Carolina, New York and Virginia; and one case each in Maine, Massachusetts, New Jersey, New Mexico, Rhode Island, Utah and Wisconsin.
Experts suspect that it is linked to an earlier outbreak of an unidentified disease in China, where officials say 305 people have fallen ill and five have died.
It is believed to be spread from the nasal fluids of those carrying it, mostly through sneezing and coughing in close contact.
The development of the test involved isolating the germ from a sick patient and mixing it with blood from recovered patients.
"The blood from the [recovered] SARS patients kills the virus, which means the virus was previously in these people and now they have antibodies that kill the virus," said Dr. Klaus Stohr, WHO's chief influenza scientist.
"What we have now is perhaps a test," Stohr said. "If you are ill and we don't know whether you have SARS or not, we take your blood, we run this test and we know whether you have it or not. But this has to be verified -- double-checked and triple-checked."
But the chief of the CDC sounded skeptical. "It's very unlikely you could have a reliable diagnostic test when you don't have an etiology," Gerberding said. She said the CDC is relying on case definitions and investigation to determine which patients have the disease.
The WHO scientist who developed the test is not certain what type of virus he isolated. However, the paramyxovirus family, which includes measles, mumps and canine distemper, remains the leading suspect. A new form of influenza, once the most feared scenario, is now low on WHO's suspect list, Heymann said.
Two separate labs reported yesterday that genetic experiments showed that some patients were infected with a new paramyxovirus, although the research could not tell whether that virus is the one causing the illness or whether it just happened to also be in the patients' specimens.
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