Hong Kong will automatically be taken off the World Health Organisation's list of SARS-infected areas on Sunday, so long as there are no new confirmed cases.

This was the message today from WHO Executive Director of Communicable Diseases Dr David Heymann, stopping off in Hong Kong on his way back to Geneva from the recent SARS forum in Kuala Lumpur. He added that Hong Kong is safe and travel should resume.

"The removal of a country on the list is an automatic process 20 days after the last case is isolated, and we understand the last isolation of a patient occurred here on June 2," Dr Heymann said.

"The recommendation to postpone travel to Hong Kong has been lifted, and now we are recommending that people travel to Hong Kong. There is no danger."

Dr Heymann praised the Government's work in dealing with the outbreak and thanked it for the assistance it has given the WHO.

Vigilance must remain high

However, he warned that vigilance must remain high as there is no guarantee the virus will not re-emerge in winter.

"Viruses which cause about 30% of common colds are seasonal and are common in the winter months. Will this be the same with SARS? We don't know," he said, adding that academic research in Hong Kong suggests the virus is less stable in high humidity.

"So maybe it is a seasonal virus and it may come back. That's why Hong Kong and China are continuing their intensive surveillance activities."

He said it is this close liaison and co-ordination between Hong Kong and Mainland health authorities that is vital in helping prevent the virus from spreading again.

"This outbreak has shown the difficulty in relationships between central, state, provincial or territorial governments when health has been delegated from a central government to a peripheral level. [Hong Kong and Guangdong] need to discuss how to have better interaction between the two [medical] systems. I know from [Secretary for Health, Welfare & Food Dr] EK Yeoh that those discussions are going on."

All countries must be on alert for SARS recurrence

He said Hong Kong and all countries must now be on alert for a SARS relapse, adding the best news is that it does not require anything but good disease surveillance and detection to control, along with good hospital prevention, control and contact tracing.

"But we have a handicap as we do not have a diagnostic test. That's what makes it such a big challenge because when winter comes there are going to be many background diseases that fit this case definition and they will all have to be treated with antibiotics to see which ones don't treat and they will all have to be isolated. It's a massive undertaking and Hong Kong's Department of Health is gearing up for that."

Patient isolation key to preventing disease spread

On the Government's study on setting up a body similar to the US' Centres for Disease Control & Prevention and an infectious diseases hospital, Dr Heymann said the WHO has no specific recommendations for or against the ideas.

"It is Hong Kong's decision. We support any way a patient can be isolated to prevent the spread of the disease to others. I believe EK Yeoh is still thinking about what the best model is for Hong Kong."