ATLANTA (AP) -- U.S. health officials said Wednesday they now have a test to determine whether coughing, feverish patients have the mystery illness from Asia.

The new antibody test isn't perfected enough to be given to doctors yet, but it is being used to help state health departments sort out whether they have cases of severe acute respiratory syndrome, or SARS.

The Centers for Disease Control and Prevention said they will soon be giving test results in suspected SARS cases to state health officials. The test detects the new form of the coronavirus, which CDC officials say they are "90 percent" sure causes SARS.

Doctors in the United States suspect that 85 people -- nearly all of them having recently traveled to SARS-affected areas in Asia -- have the illness, which has killed 78 people around the world. But physicians cannot be sure if their patients have SARS or other flu-like illnesses. This test will help confirm SARS cases, CDC Director Dr. Julie Gerberding said Wednesday.

"If a patient has an antibody response to the new coronavirus, it may be very strong evidence of an association with SARS," she said. "It's a useful tool -- what we are seeing so far are people who have the strongest epidemiological link to SARS are turning out to have positive tests."

The CDC is working to verify the accuracy of the test by checking for the antibody in people who are not suspected to have SARS. Scientists are also using the test to compare the number of suspected SARS patients who have developed the antibody versus patients who haven't.

"If (coronavirus) is truly the cause, we figure most of the people with the condition will have a positive test," Gerberding said.

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