Heightened farm biosecurity, stringent hygienic practices in farms and markets and an effective surveillance system are the key measures to tackle avian flu, says Secretary for Health, Welfare & Food Dr Yeoh Eng-kiong.

At a meeting with chicken breeders' representatives and the livestock industry, Dr Yeoh explained that vaccination could be used to contain outbreaks but it should not be seen as the only and ultimate solution to tackle the disease. 

"This strategy is internationally recognised and shared by members of the Expert Working Group on Avian Influenza when they recently reviewed the interim results of the trial of vaccination."

He said he was encouraged by the trade's positive response.

They recognised of the importance in keeping a high standard of hygiene in their farms and were prepared to take action towards this end, added Dr Yeoh.

There are a number of issues relating to vaccination that must be resolved before making a decision on a comprehensive vaccination programme.

"These include the effectiveness of vaccination in our endemic environment, means to monitor the mutation of the virus and the surveillance system to detect infection of vaccinated chickens from field virus.

The vaccination trial was originally slated for evaluation in April.

"In view of the changing situation, we will analyse the data collected so far from the trial scheme, taking into account the recent outbreaks in recreational parks, markets and farms, and consider whether there should be an early evaluation on the way forward," he said.

The United States Department of Agriculture did not formally publish results of validated scientific work using commercially available vaccines against Hong Kong's H5N1 virus until 2001. This had an impact on the trial scheme's timing. 

It would have been irresponsible on the Government's part to promote untried vaccines without sufficient supporting data.

On biosecurity at the farms, Dr Yeoh pointed out that upgrading standards was key. Once the disease is introduced into a farm either by humans or birds, it spreads quickly and affects other birds.

"As long as we have live birds in Hong Kong, the risk of avian flu will exist," Dr Yeoh said.

"The recent incidents of avian flu outbreaks in recreational parks, detection of the disease in wild birds and infection of two local farms have all pointed to the need for upgrading the biosecurity standard of local farms to the highest standard."

"Chicken farmers and market stall holders must join us in the combat against the disease by keeping their places hygienic," Dr Yeoh said. 

He said because of the endemic nature of avian influenza in Hong Kong, depopulation is no longer the only course of action to take in the event of an outbreak.