Spread of bird flu unprecedented

According to experts from the World Health Organization (WHO), meeting in Geneva, the relentless spread of the lethal bird flu virus is far more of a challenge to the world than even AIDS.

The gloomy announcement comes as Poland has confirmed the virus in two dead swans and in Austria, state authorities say that three cats have tested positive for the deadly strain of bird flu in the country's first reported case of the disease spreading to an animal other than a bird.

The cats had apparently been living at an animal shelter where the disease already had already been detected in chickens.

They were among 170 cats kept in cages next to infected birds.

The virus has to date cost some 300 million farmers more than $10 billion in its spread through poultry across the world.

Dr. Margaret Chan, for the WHO says that since February, the virus has spread to birds in 17 countries in Africa, Asia, Europe and the Middle East.

Chan speaking to as many as 30 experts in Geneva said that the agency's top priority was to keep the deadly H5N1 strain of bird flu from mutating.

Health officials say that several million doses of an initial bird flu vaccine based on a sample of virus taken from Vietnam in 2004 has been stockpiled by the U.S. but the virus is thought to have mutated since then.

A second vaccine to combat the deadly virus has apparently been authorized for development.

Health and Human Services Secretary Mike Leavitt says there is a need to continue to develop new vaccines in order to be prepared.

Such a spread in an animal disease is unprecedented and does nothing to allay fears the virus will ultimately mutate into a form easily passed between humans, triggering a global pandemic.

Officials in China have reported the death of a man southern Guangdong province from the H5N1 virus.

The region borders Hong Kong and as there have been no reported outbreaks in birds in the area where he died, experts in Hong Kong are urging authorities to find the source of the latest case.

Experts in Hong Kong are now querying the efficiency of surveillance of the disease in China.

The virus remains essentially an animal disease which humans contract through close contact with infected birds.

There have been to date 95 deaths since 2003 and 175 people have become ill.

The virus is currently spreading rapidly among wild birds and has reached at least 15 new countries over the past month, moving across Europe and also hitting Egypt and West Africa.

Animals carrying H5N1 without showing any signs of ill health could make it harder to detect and contain bird flu and the longer the virus remains in a mammal, the greater the risk of it mutating into a more dangerous form.

The WHO says though there have been no examples of cats infecting humans there is much to still be learned about cats and their possible role in spreading bird flu.

A hefty blow has been dealt to the poultry industry by the rapid spread of the virus and heightened fears for human health.

The cost to agriculture to date is estimated at around $10 billion, and 300 million farmers have seen their livelihoods affected.

France, Europe's largest poultry industry, is losing 40 million euros ($48 million) a month after an outbreak of H5N1 at a poultry farm.

The news prompted more than 40 countries to impose curbs on French poultry products, including foie gras.

Health experts continue to urge people to continue eating chicken as long as it is well cooked and stress there is no risk from cooked meat, but fears over the virus have seen consumption plummet.

Public health measures to quarantine areas, isolate people or help give antiviral medicine to those infected with bird flu are says the WHO measures that can buy time for health authorities to improve their response strategies and stave off the disease until a pandemic vaccine can be produced.