H5N1 strain could trigger flu pandemic
Posted April 1, 2005
Chief veterinary officers from 28 countries are calling on Asian governments and the international community to make the fight against avian influenza a top priority by increasing funding for campaigns to eradicate the virus before it sparks a flu pandemic.
The United Nations Food and Agriculture Organization and World Organization for Animal Health (OIE) organized the conference on the highly pathogenic H5N1 avian influenza strain, held Feb. 23-25 in Vietnam and Rome, in collaboration with the World Health Organization.
The WHO has confirmed 69 human cases of H5N1 infection in Cambodia, Thailand, and Vietnam since January of 2004. Of those infected, 46 died—a 66 percent mortality rate.
Animal and human health experts at the conference agreed that progress has been made in the early detection of and rapid response to the disease. There are fewer outbreaks in the region today than were recorded one year ago.
The H5N1 strain is still circulating among poultry, ducks, and wild birds in the region, however, and continues to pose a serious threat to human and animal health.
There are between 25 million and 40 million backyard poultry farmers in Cambodia, Indonesia, the Lao People's Democratic Republic, Thailand, and Vietnam. Most poor farmers keep poultry for income and food.
Conference participants acknowledged the link between farming systems and the spread of the virus, namely, that the proximity between farmed chickens and ducks in many backyard farms is contributing to the circulation of the disease.
The virus circulation in poultry-producing rural and urban areas and marketplaces requires more attention, according to participants. As long as it continues circulating, the virus remains a threat to public health because it could mutate into a strain capable of sustained person-to-person transmission.
Moreover, the movement and marketing of live animals not controlled by veterinarians are a major cause of the spread of the disease.
Participants concluded that more funds and more-vigorous bird flu control campaigns in affected countries would help control the disease in birds, avoiding an avian influenza pandemic in humans.
In addition, countries dealing with H5N1 must take a more proactive approach to combating the disease. Funding for this approach is considered essential, according to participants.
Massive public awareness campaigns are necessary to sensitize poultry producers and consumers about bird flu-related risks. Farmers and veterinarians should become the main allies in detecting the virus at the earliest stage possible to trigger immediate control interventions.
At the conference, several strategies were recommended to minimize the risk of virus transmission among bird species. For instance, segregating at-risk animals on the farm reduces their contact with one another.
Delegates called on the global community to help with the financing of these changes. More than $100 million would be needed to strengthen animal health services and laboratories to improve virus detection.
Several hundred million dollars would be required to finance the restocking of infected poultry flocks and to restructure the whole sector, according to participants. There was also agreement that vaccines would greatly help reduce the disease in poultry. The possibility of vaccinating ducks should be explored as well.
Participants did acknowledge the need to further study conditions in which vaccines can be delivered with minimum risk to human health, however.
One effort already under way is the new, worldwide Avian Influenza Network launched this April by the OIE and FAO.
The network means to develop and coordinate research projects related to the bird flu in various parts of the world. This sharing of current scientific information and efficient control methods of the animal disease is intended to help eradicate the virus in infected countries and protect virus-free countries.
Information on national and regional epidemiologic activities will be gathered by the network, which has a system of laboratories to work on vaccines for humans. Wherever required, viral strains will be shared with the WHO Network of Influenza Reference laboratories.