Avian influenza prevention activities should include better management practices in farms

Aug 13 2005

Wildlife health experts from the Bronx Zoo-based Wildlife Conservation Society (WCS) warn that efforts to control the spread of avian flu across Asia and beyond must focus on better management practices on farms and in markets.

WCS is currently working with Mongolian agencies on the ground in Mongolia's Kovsgol province, collecting samples from wild birds that have recently contracted the virus.

"We're working with our Mongolian and international partners to confirm and track the movements of Avian flu in the region," said Dr. Billy Karesh, head of the WCS team currently in Mongolia. "The best hope for successfully containing the spread of avian flu is focusing our limited resources on the hubs where humans, livestock and wildlife come into close contact."

According to WCS, avian influenza prevention activities should include better management practices in farms, especially small open-air farms where domestic poultry and waterfowl are allowed to intermingle with wild birds. Wildlife markets--where wild and domesticated species are kept in close proximity--are also hubs of transmission for avian flu and other pathogens that need to be better regulated. Wildlife and health experts also maintain that indiscriminate culling of wild migratory bird populations would be ineffective in preventing the spread of the disease.

The outbreak of avian influenza in Mongolia has coincided with confirmations of cases in Russia and Kazakhstan. The initial reports of avian influenza came from the Mongolian Ministry of Food and Agriculture, which conducted preliminary testing of birds that died at Erkhel Lake in the Kovsgol province near the Russian border.

A joint WCS-Mongolia team that was working in western Mongolia immediately went to the site to collect more samples that will be sent to the United States Department of Agriculture for further testing to determine the strain. These tests will determine if the virus is the H5N1 strain that has killed over 50 people in Southeast Asia and more than 5000 wild birds in western China.

The team, in an unprecedented, international multidisciplinary effort, includes members of WCS, the Mongolian National Academy of Sciences, the Mongolian Institute of Veterinary Medicine, the State Central Veterinary Laboratory, Ministry of Food and Agriculture Veterinary Department, and the Ministry of Health Mongolian Center of Communicable Diseases with Natural Foci.

"The Mongolian governmental agencies working on this are to be commended for keeping the international community informed on this important health issue," said Dr. Robert Cook, WCS Chief Veterinarian. "This is the type of collaborative 'One World, One Health' effort that is vital in keeping potential epidemics contained."

In light of the recent outbreaks of avian flu in other regions, WCS proposed and with the United Nations Food and Agriculture Organization funded an expedition to Mongolia to examine the role of wild birds in the spread of avian influenza.

Previously, outbreaks in wild birds have either been in close proximity to infected domestic poultry and waterfowl, or in regions where contact with domestic poultry could not be excluded. As Mongolia has few domestic poultry, finding the H5N1 virus in wild migratory birds here would indicate that wild birds can become infected and move highly pathogenic avian influenza long distances. "Wild birds are sick and dying, so they may be the victims rather than the vectors of the disease. Laboratory testing from surviving birds will tell us if they are able to carry the virus during the migration" explained Dr. Karesh. This information will allow countries in the region to protect human and domestic animal health by limiting contact with wild birds and increasing surveillance for the virus on poultry farms.