Bird flu found in Thai cats

Two domestic cats in Thailand have died of the same bird flu that has killed at least 22 people in Asia, a veterinarian said yesterday, a day after Canada announced its first case of a different strain of the virus.

The discoveries have alarmed scientists, who now fear the disease can spread as easily between species as it has between countries.

They said yesterday developing human vaccines must be a priority to prevent a flu pandemic like the one in 1918 that killed up to 50 million people worldwide.

"It is a pandemic threat constantly simmering," Dr Marion Koopmans, of the National Institute of Public Health and the Environment in the Netherlands, told Reuters in London.

China confirmed two more suspected outbreaks of the influenza H5N1 virus in two provinces yesterday, and Thai officials said the virus had reappeared in two provinces that had been declared under control.

With the virus spreading at an unprecedented rate through poultry, and with 22 people dead in Asia, researchers warned it poses a substantial threat to human health.

In two reports in the Lancet medical journal, Mr Koopmans and Professor Malik Peiris of the University of Hong Kong, who both dealt with previous cases of animal-to-human transmission of flu, described why the current avian outbreak is so dangerous.

Mr Koopmans said it is possible the virus may not be completely controlled in poultry because it is so widespread, which furthered the case for making a vaccine a top priority.

An Australian government research lab said a locally developed drug, Relenza, used for treating human influenza, had proven effective against bird flu in laboratory tests.

The virus has also crossed the species barrier to domestic animals, and in Bangkok yesterday scientists confirmed the deaths of two house cats.

"We found H5N1 in two of the three cats," said Teerapol Sirinaruemit, a veterinarian at Kasetsart University's animal hospital, who conducted autopsies on three animals.

"They might have caught the virus from eating chicken carcasses or from live chickens that had bird flu," he said.

The three were among 15 cats living in a house located near an infected chicken farm 60 kilometres west of Bangkok, Teerapol said.

Fourteen cats died, but it was unclear if all had been infected with the H5N1 virus. One cat was still alive.

"We are going to bring the live one, which is quite sick, to the hospital today to check its health," Teerapol said.

The Food and Agriculture Organisation said yesterday the cat deaths required "more careful scientific analysis".

"We also need to know what specific diagnostic tests were performed and how the testing was carried out," the Rome-based group said in a statement.

"FAO advises that cats or other carnivores or omnivores (i.e. swine) should not be fed with carcasses of dead or culled birds." Besides killing humans and millions of wild and farmed birds across Asia, the H5N1 strain showed earlier this week it can jump to other species after a rare clouded leopard at a zoo near Bangkok was confirmed as dying of bird flu.

Reports earlier this month that the virus had spread to pigs, with an immune system similar to humans', turned out to be false.

"Clearly the more animal species that are infected with the avian flu virus, the bigger is the risk to humans they may catch the virus from animals," Bjorn Melgaard, the World Health Organisation's Thailand representative, told Reuters.

"We need to be very, very watchful."

Meanwhile, the Canadian Food Inspection Agency was still conducting laboratory tests, but officials said they had identified the H7 strain of avian influenza in British Columbia - the same type found recently in Delaware in the United States.

Japan reacted immediately, saying it was halting all imports of poultry from Canada.

As news of the virus infection in cats spread, Thai Prime Minister Thaksin Shinawatra cautioned Thais not to feed their pets uncooked chicken meat.

"Please don't panic," Mr Thaksin told reporters in Bangkok. But he added: "If animals eat raw infected chicken, they will have no immunity."