THE deadly respiratory disease that has killed dozens of people in China, and 17 in 14 other countries, has been called a "white terror" and likened to the early days of the AIDS epidemic.

In hard-hit Hong Kong, exhausted medical experts are struggling to contain the outbreak of Severe Acute Respiratory Syndrome, which spread late last year from Guangdong province in southern China.

Dozens of Hong Kong healthcare workers have been infected by the disease, which has hit 286 people in the territory.

President of the Hong Kong Society of Surgeons and dean of medicine at the Chinese University, Sydney Chung Sheung-chee, said yesterday he was personally devastated by the outbreak.

"It is a holocaust," he told the South China Morning Post.

"It is a war with an unknown enemy. It is the worst medical disaster I have ever seen."

The Prince of Wales Hospital, where Dr Chung treats SARS patients, has had 69 medical staff struck down by the illness.

"I feel terrible seeing my colleagues struck down one after another," Dr Chung said.

He said one doctor's lung function was "totally destroyed", highlighting the stress such cases cause among professionals.

China admitted yesterday that the number of mainland deaths was almost five times the number previously acknowledged and infections were double the number revealed by officials until now.

Guangdong officials point to news reports that said 24 people had died and 680 had been infected in that city by the end of February.

SARS is poorly understood and scientists have yet to nail down its cause.

Chairman of the Communicable Disease Network of Australia David Smith said it was not unlike the beginning of the AIDS epidemic.

As with HIV-AIDS, medical and health professionals were struggling to pin down the infectious organism and must work with "very broad" definitions of the symptoms, Associate Professor Smith said.

Once experts identified the pathogen, along with its origin and behaviour, they would be better able to treat SARS and prevent its spread.

But progress is being made. Experts now know masks, gowns and protective clothing limits the disease's spread.

A World Health Organisation team has arrived in Beijing to help scientists with laboratory work and review evidence linking the Guangdong and Hong Kong outbreaks.

Australia's WHO team leader John Mackenzie, of the University of Queensland, said his Chinese colleagues had provided "very good data" on the Guangdong outbreak between November and February, but there was a "long way to go".

In Australia, three people are under investigation, but so far no cases have been confirmed.

The Australian