Officials at a U.N. sponsored scientific meeting in Rome this week [5/30-31] downplayed the role of migrating birds as the major source for the spread of the highly pathogenic H5N1 virus.

Juan Lubroth heads the infectious disease group for the Food and Agriculture Organization

Juan Lubroth heads the infectious disease group for the Food and Agriculture Organization. He says human activity presents a far greater risk. "Commercialization, the way we produce our animals, the way we market, the way we do not have the proper hygiene or inspection," he says. "It is through the poultry trade, not so much the wild birds. They [wild birds] will introduce it, but we are responsible for [spreading] it."

Strategies like monitoring poultry flocks and vaccinating the birds can help target the virus at its source and slow down its spread, according to Christiane Bruschke with the World Organization for Animal Health."We need to increase sanitary measures," she says. "We need to increase bio-security. We still need to kill infected animals, but certainly [poultry] vaccination can be a good tool in different circumstances."

Post Mortem inspection in Cambodia. Once established, avian influenza is extremely contagious

Since 2003, when it was first identified, the deadly virus has moved from Asia to countries in Africa, the Pacific, Europe and the Near East, and is responsible for the deaths of more than 200 million birds. The virus has infected 224 people in 10 countries, largely through contact with infected poultry.

FAO veterinary officer Joseph Domenech says outbreaks in Africa are the most worrisome because of the region's inability to respond in a timely manner. "It takes time to react, to respond," he says. "It took two months in Nigeria, for example, and by that time the virus is spreading all over the country. He says the situation is related to the difficulty of the veterinary services and animal health surveillance systems to cope with the situation and to respond immediately. "That's why there is a need for a huge investment to support these systems."

FAO estimates it will need approximately $308 million over the next three years to control the virus. So far the organization has received just $71 million in funding.