By Tonny Chan (HK Edition)
Updated: 2005-10-26 06:19

Health officials yesterday urged the public to beef up readiness for a possible avian flu outbreak in Hong Kong by raising the alertness to "personal level".

They said observing personal and environmental hygiene was the key to protection against a flu pandemic.

They also urged the public not to take antiviral drugs without the advice of doctors, saying their indiscriminate use could trigger a chain of biological mutations and render the protection plan futile when real emergency occurred.

The appeal for a community-wide alert was made after mainland health officials confirmed an avian flu outbreak in a local poultry concentration in Anhui Province. The local authorities have already culled all the fowls within a radius of 5 kilometres. There is no report of human infection in the outbreak.

Professor Yuen Kwok-yung, who chairs the Scientific Committee on Emerging and Zoonotic Diseases (SCEZD) of the Centre of Health Protection (CHD), said people could lower the risk considerably if they were prepared at a very personal level.

Yuen urged the public to observe the authorities' advice for good personal hygiene (see table), saying it was of "paramount importance" to wash hands frequently and properly.

Hand washing

"Frequent and proper hand washing is of paramount importance," Yuen said. "People should also stock up several weeks' supplies of surgical masks, tissue papers, liquid soap, disinfectants, thermometer and anti-pyretics at home," he said.

"Washing hands is the most important weapon we have in combating the virus," he said.

Expressing fears that some people may rush to take antiviral drugs indiscriminately on the misunderstanding that the drugs would protect them from infection, Yuen said it would be dangerous to do so as this may give rise to a super-virus resistance to the medicine.

The risk, according to him, is that after a healthy person has taken antiviral medicine continuously for a good while, should he become infected with flu, there is a 10 to 18 per cent chance of the disease being resistant to the antiviral drug.

If the patient were unfortunate enough to be also infected with avian flu, the human flu strains that have developed resistance would marry with the avian flu to pass on the resistance. Were this to occur, the SAR would be left in a limbo when attempting to contain an outbreak.

Yuen said the danger was not theoretical and could become real unless the community played its part in avoiding the unnecessary use of antiviral drugs. But he added there was still no cause for public panic.

The medical scientist also asked individuals and companies not to stock up on antiviral drugs, suggesting they should consult their family or company doctors, leaving medicines with their physicians if they insist on resorting to such contingency measures.

Speaking of the stockpile the SAR is building up, he said it was necessary to prioritize the use because of tight supplies worldwide.

According to him, antiviral drugs would be considered for the treatment of infected patients, pre-exposure prevention treatment for healthcare workers, essential service providers and workers involved in culling operations and post-exposure prevention for those who have direct contacts with the infected.

This is the first time since the SARS outbreak in 2003 that the authorities have gone public again to make a high-profile appeal on personal hygiene.

Yuen said that while Hong Kong was still relatively safe, thanks to the stringent safety and surveillance measures, the risk was imminent.

Likely routes

He said there were two major ways for avian flu to get into the SAR: first, through wild birds; second, through poultry imports, though there was also a smaller chance of an outbreak being caused by careless leaks from laboratories.

"Thus, we are maintaining an extremely high level of security at our laboratories," Yuen said, drawing a vague reference to the 1977 outbreak of influenza H1N1 that was traced back to a Soviet laboratory as the source.

He believed the world was very close to the next pandemic even though he did not know when it would happen.

The first recorded flu pandemic was caused by H2 strains in 1889, followed by H3N8 strains in 1900, H1N1 in 1918, H2N2 in 1957, H3N2 in 1968 and H1N1 in 1977. Millions of lives were lost. Had it not been for the H5N1 outbreak in the SAR in 1997 and now in Asia and Europe, experts would have predicted the next pandemic to be one caused by H2 or H3 strains.

Yuen said there had been 37 years since the last pandemic in 1977 whereas the longest period between pandemics in history was 39 years.

Well informed

A spokesman for the Health, Welfare and Food Bureau said yesterday the SAR was informed of the Anhui outbreak by the mainland on Monday afternoon." We're monitoring the development closely," said the spokesman. Anhui does not export poultry products to Hong Kong.

Thomas Tsang, consultant of CHD, said the health authorities had a stockpile of 3 million capsules of antiviral drugs and would receive an extra shipment of 4 million doses in the first quarter next year. The eventual target is to expand the stockpile to 20 million doses.

Tsang said they would not take claims of successful vaccines seriously until after they were proved and became commercially available for mass inoculation.

Yuen clarified that currently available flu vaccines could not prevent the illness but would reduce the chance of complications and hospitalization arising from ordinary human flu among high-risk groups such as the elderly and those chronically ill.

The CHD will create on its website www.chp.gov.hk a new section of frequently-asked-questions about flu pandemics and antiviral drugs to provide authoritative and practical information to the public. The public can also obtain information on flu or avian flu from hotline 2833-0111.

Yuen gave this reminder: "Washing hands is the most important weapon in fighting the virus."

(HK Edition 10/26/2005 page2)