Bird flu believed endemic in Asia, spreads to pigs

The discovery of a deadly bird flu strain in Malaysia after cases elsewhere in Southeast Asia signalled a major winter outbreak was likely, international health experts say.

Since a strain deadly to humans emerged in Asia early this year, scientists have voiced fears the flu could mutate, become able to jump to humans, and spread.

Adding to concern was an announcement by a Chinese scientist on Friday that pigs in China had been found infected with bird flu, but the World Health Organisation said that did not come as a complete surprise.

A strain of bird flu blamed for 27 deaths in Asia this year has been found in Malaysia this week and hundreds of birds have been gassed this week and their carcasses burned to contain the outbreak.

The latest deaths from the H5N1 strain of avian influenza were of three people in Vietnam earlier this month.

"This is a great concern. It says to me that the virus is endemic in the region," virologist Dr. Robert webster of St Jude Children's Research Hospital in Memphis, Tennessee, told a Beijing symposium.

China had found pigs infected for the first time with bird flu in 2002 and 2003, Chen Hualan, a member of the China Academy of Agriculture, told an conference on avian flu and Sars. "This is a somewhat dangerous signal for public health," she said.

WHO representative Henk Bekedam said: "We know that pigs can carry human virus as well as bird flu virus.

"We need a lot more information before we can make comments on that... We also know that the virus so far has been very ineffective in being easily transmitted to humans, let alone between humans."

The fear is that human and bird flu virus could mix in pigs and form a strain more easily transmittable to humans.

The outbreak in Malaysia was the country's first and no human cases have been confirmed.

A teenager from the village at the centre of the Malaysian outbreak had been taken to hospital with cold symptoms but officials said there was no indication from initial tests that she had contracted the bird flu virus.

Malaysia's poultry industry faces huge losses as export markets close and livestock prices fall. And restaurants specialising in chicken dishes in the capital Kuala Lumpur had noticeably fewer customers on Friday.

"Usually we are jam-packed on Friday and Saturday because the food is good," said Raul, a waiter at Mediterranean grilled chicken outlet Nando's.

"But today, it is down. Maybe 10 to 20 per cent less customers."

A total of 15 outbreaks of highly pathogenic avian flu have been reported since 1950, five of them big, said Dr Klaus Stohr of the Department of Communicable Disease Surveillance and Response under the WHO Global Influenza Programme.

"The one this year is even bigger. What we are seeing is completely unprecedented," Stohr told Reuters on the sidelines of the Beijing symposium.

"The probability of the continuation of the outbreak is relatively high. The virus appears endemic, with a foothold in domesticated bird populations."

In rallying to stem the spread of the disease, many Asian countries could look to China as a model, health experts said.

China has had success in controlling outbreaks of bird flu, mostly in its southern provinces, despite being the world's most populous country in terms of both humans and poultry.

China has vaccinated more than 11 million birds and culled 8 million to rein in outbreaks that have infected 150,000 birds and killed 120,000 this year, Chen Hualan said.

China also suspended exports of chilled ducks and geese to Hong Kong on Aug. 2.

"The key element in control and prevention is controlling birds' movements," said Stohr.

Trading of fighting cocks may have circumvented control measures in Thailand and Vietnam and led to outbreaks in areas thought to be safe.

Migrating birds pose a potentially greater danger because infected birds could pass the virus to uncontaminated populations of domesticated poultry.

"That would be a new paradigm, making it not only endemic in poultry, but circulating, and that would complicate control efforts," Stohr said.

- REUTERS