HONG KONG (May 3) - Like a ``murderer who is trying to change his fingerprints,'' the SARS virus is mutating rapidly into at least two forms, complicating efforts to develop a solid diagnosis and a vaccine, researchers say.

Scientists at the Chinese University of Hong Kong say they analyzed the genetic sequences of virus samples taken from 11 SARS patients and found by late March that two forms of the virus were present in Hong Kong.

One strain was detected in a woman whose illness was linked to an outbreak caused by a mainland Chinese man who spread SARS to others at a Hong Kong hotel.

The other strain came from a Hong Kong man believed to have caught it in the mainland border city of Shenzhen.

``This rapid evolution is like that of a murderer who is trying to change his fingerprints or even his appearance to try to escape detection,'' said Dr. Dennis Lo, a chemical pathologist at the university.

But while Lo said researchers have shown ``the SARS coronavirus is undergoing rapid evolution in our population,'' he noted more work is needed before researchers can say whether the virus has become more infectious and lethal.

Researchers also need to find out whether people who get SARS from one strain can develop immunity to other strains, he said. If not, finding ways to better diagnose it and to develop a vaccine could be more difficult.

The World Health Organization says there's no evidence that the mutations have any effect on the disease itself. WHO scientists also say it's not surprising the SARS bug shows genetic changes, because the coronavirus family is prone to mutations.

A U.S. coronavirus expert, David Brian, at the University of Tennessee in Knoxville, agreed that a rapidly mutating SARS virus could complicate work toward a vaccine and reliable diagnostic tests.

The crucial question is where the mutations occur in the SARS virus genome, he said. If they affect the shape of an outer protein on the virus, it could hamper vaccines, which rely on training the immune system to recognize particular protein shapes, he said.

Diagnosis, meanwhile, is based on specific features of the bug's genetic sequence. So if one of the crucial features is removed by mutation, the detection kit becomes less sensitive to recognizing the virus, he said.

Hong Kong scientists are also concerned that the virus may survive in an infected person's body for at least a month after recovery. Doctors are urging patients to avoid personal contact such as hugging and kissing when they go home.

``The virus still exists in the patients' urine and stool after they were discharged. It will persist for at least another month or maybe even longer,'' said Dr. Joseph Sung, head of the Department of Medicine at the Chinese University of Hong Kong.

What's more, scientists here also fear that 12 people may have relapsed. The new findings raise questions as to how doctors can tell whether a patient has fully recovered, underscoring the difficulty health authorities face in tackling this new disease.

Sung, who works at the Prince of Wales Hospital, which was hard-hit by SARS, has monitored the cases of about 240 recovered SARS patients. He said none has spread the disease to others.

If recovered patients wear masks, avoid close contact with family members and are particularly careful about toilet hygiene, things should be ``quite safe'' in their households, he said.

Sung believes the virus can survive in the environment longer than a day. ``If your saliva gets on a table surface, don't assume that it will be all right after it dries up,'' he said.

Dr. David Heymann, WHO's chief of communicable diseases, said the relapses are disappointing, and it's not clear what caused them. He said he hadn't heard of similar reports outside Hong Kong.

``We don't yet have the data ... as to exactly what has happened, what these people were treated with,'' Heymann said. He said one theory is that some relapses may have happened because patients stopped taking steroids too quickly. The steroid therapy is being prescribed in Hong Kong.

Heymann said in some other infectious diseases, it's not uncommon to find virus in body excretions after a patient's symptoms are gone.

``So it's not a new phenomenon that viruses remain, but certainly a relapse is concerning,'' he said.

05/03/03 10:36 EDT
   
Copyright 2003 The Associated Press. The information contained in the AP news report may not be published, broadcast, rewritten or otherwise distributed without the prior written authority of The Associated Press.  All active hyperlinks have been inserted by AOL.

here's another one:




400/6000 ~ 6.66% [devil]

This is gonna cause problems too:


What about all the people who never got sick enough to go to the hospital? They are going around infecting everyone even after they think they are well enough to go back to work.

good question

from what I've read it seems like we get to wait and see -- no one knows yet

This is gonna get ugly/uglier.

It sounds to me like it Could go either way. What if the bug meets another of it's kind and mutates to a real nasty??
I'd like to get the opinions of some of the pros, like soylent and some others. Maybe there's a researcher or 3 who hang here?? [:D]

Okay folks. The skinny I got on SARS is that if you're under 65 and in good health you'll have a 95% chance of survival. The Idiots in the news refuse to report this fact therefore spreading panic. Similar to what was reported with tainted raw oysters; If yer older than 6 and younger than 70 you had a 90% chance of getting a case of diarreah. Everyone else gets it terminally only 5% of the time. Do the math.

if i remember right, the spanish flu pandemic killed something like 30 million people

its fatality rate was about 4%

The correct answer is that it COULD be a new pandemic equal to the one of 1918 IF people don't take it seriously. It hasn't been around long enough yet to say for certain about how it can spread against modern medicine. Where it has struck it has been pleanty lethal enough. People keep trying to poo poo the seriousness of the treat it poses, but if is NOT hyped up measures to control it will be difficult to empliment-especally as the only control method is isolation, essentially imprisonment.

Only 2.2% in the US.

aha, and as heartless as it seems, most of us are probably more concerned about how this thing will act locally as opposed to world wide


by the way, the 400/6000 ~ 6.66% thing should actually be

400/(6000 + 400) ~ 6.25%

percent of those infected who die

Unless you spend alot of time in overcrowded  areas like Prisons, Hospitals, College dorms, high rise apartments, then I dont think your going to have to worry to much.

Exceed the carry capacity of any habitat and darwin will thin the heard.

Military bases too.

That is where the 1918 flu started.

better hope your fast food cook washes well after he wipes his ass