"Even if you control avian flu, the next one is coming," said Dr Shigeru Omi, WHO's regional director for the Western Pacific, which stretches from China to Fiji.

"I think it is similar to tsunamis and earthquakes ... we do not know when," Omi told WHO's Western Pacific annual conference in Noumea, capital of New Caledonia in the South Pacific.

Avian flu was first detected in South Korea in 2003, only months after SARS was contained, and quickly spread within months to Taiwan, Vietnam, Indonesia, Thailand, Malaysia and China.

The contagious H5N1 strain of the disease has since killed 64 people in four Asian countries and has spread to Russia and Europe, sparking global fears it could mutate and become a pandemic killing millions of people.

The latest deaths prompted Indonesia on Wednesday to say an outbreak in the capital Jakarta could be called an epidemic.

Millions of poultry have been culled since 2003, but bird flu still spreads.

"In my view this is connected by the differences in the farming practices. In the West farming practices are well controlled -- ducks, chickens and humans do not mingle together," Omi said.

"Unless we address this fast we have to expect more emerging diseases, particularly zoonoses." Zoonoses is the spread of disease from animal to human.

HIGH POPULATIONS, CONTACT

Omi said the spread of avian flu in Asia over the past two years had correlated with areas of high populations and high human-to-poultry contact.

"If you look at the poultry density for Asia, southern China, Vietnam, Cambodia have very dense populations. In the past two years outbreaks of avian influenza correspond to where (poultry) population density is very high," he said.

Cambodia and Vietnam, where poultry is farmed in backyards and where farmers live in close proximity to chickens and ducks, have bore the brunt of avian flu deaths.

Omi said Western Europe had equally dense poultry populations but did not experience the same level of diseases as Asia.

WHO said 75 percent of infectious diseases in the past 30 years originating from animals (zoonoses), and the Asia-Pacific was "the epicentre for such epidemics".

Dengue fever, Japanese encephalitis, leptospirosis, Nipah virus and drug-resistant malaria are some of the diseases now entrenched in the region, it said.

Omi said globalisation, which had seen an increase in the movement of goods and people in Asia, and common borders had also contributed to the spread of diseases, like SARS and bird flu.

"There is an urgent need to strengthen inter-country and bioregional collaboration," he said.

WHO's "Asia-Pacific Strategy for Emerging Diseases" plan launched on Wednesday calls for greater co-operation between Asia-Pacific nations to ensure early detection and rapid response to emerging diseases.

The plan said that although most countries had surveillance systems for communicable diseases, they were not capable of being used as early warning systems.