Scientists advance the fight against SARS

Scientists in Hong Kong said on Tuesday they have devised a new way to identify chemicals that can counter new and dangerous viruses, such as SARS, and these chemicals may be developed into drugs.

However, a cure for diseases such as severe acute respiratory syndrome, which killed more than 800 people worldwide last year, may still be a distant prospect as researchers have yet to begin animal and human testing, the scientists said.

Using a method, developed jointly by the University of Hong Kong and the Aaron Diamond AIDS Research Centre, new viruses are screened against a chemical library of more than 50,000 molecular compounds.

The scientists recently tried out the new approach, called the high-throughput screening platform, on the SARS virus and found that 104 of the chemicals could arrest the bug.

Richard Kao, research assistant professor of microbiology at the University of Hong Kong, said the screening process may be applied to any emerging virus.

"When there is a new virus, we can jump onto this high-throughput screening platform and screen more than 50,000 molecules and see which one of them can stop the virus from killing cells," Kao told a news conference.

"We expect around 100 of these molecules to be able to inhibit any new virus. We will then take these 100-plus molecules and see if any of them are suitable for testing in animals."

If these could effectively inhibit the virus in animals and were not toxic the molecules could be tried in clinical trials on humans, Kao said.

However, it is too early to say if a SARS drug could be developed with the new method.

Nearly 300 people in Hong Kong were killed by the SARS virus. It surfaced in southern China and was brought into tiny, congested Hong Kong by travellers. It has never been established how the virus jumped the species barrier from animal to human.