Bird flu comes back to haunt Asia

Bird flu comes back to haunt Asia

Ben Rowse Agence France-Presse Hanoi

Bird flu has come back to haunt Asia, just months after governments rushed to declare victory over the disease that killed 24 people and decimated poultry stocks across the region.

China, Thailand and Vietnam have all reported fresh outbreaks of avian influenza, confirming earlier warnings by international disease control experts that the virus would strike again.

"We said at the time that it would take a year to completely clear the virus from the environment. So we are not entirely surprised by these developments," Peter Cordingley, spokesman for the World Health Organization's (WHO) Western Pacific Office in Manila, told AFP.

"The question we are working on is whether these are just isolated vestiges of the major outbreak that started in January or whether we are looking at a new potential crisis."

When Vietnam declared on March 30 that it had contained the lethal H5N1 strain of the virus, 15 days after claiming its 16th fatality in the country, it was criticized for acting prematurely and recklessly.

The WHO warned that it could take months, probably years to eliminate the virus from the environment and recommended that farmers wait three months from the last infection date before restarting production.

Its advice, however, was ignored, and just weeks after Hanoi's victory declaration the first suspected recurrence occurred in the southern province of Dong Thap. Subsequently, outbreaks have been reported in five other provinces.

Meanwhile, Thailand, which has repeatedly had to postpone plans to declare itself free of bird flu, confirmed Wednesday a fresh outbreak of the deadly H5N1 strain, dealing another blow to its already struggling billion-dollar poultry industry.

This came a day after China, one of the world's biggest poultry producers, announced that H5N1 had been detected on a farm in the eastern province of Anhui, nearly four months after claiming victory over the disease.

Vietnam has not formally linked H5N1 to its new outbreaks, but says it is assuming it is present and consequently will not send samples to overseas laboratories for analysis.

The WHO, however, says it is essential to formally identify the virus and to determine if it has undergone any genetic changes.

At the height of the crisis earlier this year, the UN agency warned that H5N1 had the potential to kill millions of people across the globe if it combined with a human influenza virus to create a new, highly contagious strain transmissible among humans.

Currently, H5N1 can only be transmitted from birds to humans, sometimes with fatal consequences, but not from humans to humans.

But the proximity of farm fowl to humans, and also to pigs, which can harbor both avian and human viruses and act as a vessel to mix them, poses a special threat, experts say.

Chinese researchers from the University of Hong Kong and Shantou University Medical School have warned that the chances of stamping out bird flu are slender.

In a study of the genetic ancestry of the H5N1 virus to be published on Thursday in the British weekly science journal Nature, they warn the agent is firmly established in duck and chicken flocks in China and other countries, and will only be rooted out by a dedicated, long-term campaign.

"H5N1 virus is now endemic in poultry in Asia and has gained an entrenched ecological niche from which to present a long-term pandemic threat to humans," the study said.

The scientists warned that governments in the region "face an endemic and recurrent problem that presents a serious threat to human health".

"These developments pose a threat to public and veterinary health in the region and potentially the world, and suggest that long-term control measures are required."