Homeland Security

25 November 2005

China, Vietnam Report More Human Cases of Bird Flu

International plan to track migratory species taking shape

By Charlene Porter
Washington File Staff Writer

Washington – Vietnam, which has experienced more human cases of bird flu than any other nation, has reported the occurrence of disease in a 15-year-old boy, according to a November 25 announcement from WHO.

The boy has been released from the hospital and is recovering from the disease, which has caused severe respiratory symptoms and organ damage in some of the people infected.

On November 24, WHO affirmed a report from China’s national health agency of another human death from the highly pathogenic avian influenza virus that has led to the deaths or culling of more than 150 million birds across Asia.

China has detected a total of three human cases of the disease, resulting in two deaths, both in women who had direct contact with poultry. The dangerous H5N1 virus can be transmitted to humans through contact with the birds, their excretions, or surfaces touched by those excretions.

Vietnam has experienced 93 human cases of the disease with a total of 42 deaths since the H5N1 virus began appearing among Asian flocks about two years ago.  Indonesia, Thailand and Cambodia are the other nations where human disease has been reported.

The WHO accounting puts the total of human cases at 132 with 68 deaths.

Along with new human disease being reported in China November 24, more animal disease is reported in western provinces and authorities are continuing measures to eradicate exposed flocks and prevent the virus from spreading.

According to Chinese official reports to the World Organisation for Animal Health (OIE), almost 67,000 birds were destroyed in the Ningxia region and more than 99,000 in the Yunnan province.

No evidence has emerged that H5N1 is transmitted efficiently among humans, but international health experts warn that H5N1 could mutate into a viral strain that is contagious, creating the conditions for an international influenza pandemic.

International concern about this possibility has mounted considerably in recent months with new attention focused on the need for stronger actions to stop the disease in animal populations to avert further mutation of the virus and transmission into human populations. (See related article.)

WATCHING FOR DISEASE IN MIGRATORY BIRDS

The Convention on Migratory Species (CMS) has adopted a plan to design a system to monitor migratory flocks for disease and warn nations of the potential for the arrival of disease in seasonal movements of birds. 

The convention met November 21-25 in Nairobi, Kenya, and agreed to develop an international wildlife warning system with support and funding from the U.N. Environment Programme (UNEP).

“Precise information on the places where migratory birds go including their resting sites and finally destinations is currently scattered across a myriad of organizations, bodies and groups,” said UNEP Executive Director Klaus Toepfer in a press release. “It is absolutely vital that this is brought together in a way that is useful to those dealing with the threat of this pandemic backed up by high quality, precision mapping.”

A CMS official said it might take two years to develop the appropriate monitoring system, but the system would have both short- and long-term value because the potential for flocks of wild birds to be transcontinental carriers of infection will be an ongoing problem.

Migratory birds are suspected of transporting H5N1 from Southeast Asia to North and Central Asia and on to Europe.  International organizations have issued warnings about the possibility that cases will start appearing in Africa as migratory flocks make their seasonal journeys escaping the Northern European winter.

Though the role of wild birds in transmitting disease is assumed widely, it has not been proven scientifically.  It is also possible that the virus could be transported great distances in shipments of birds in agricultural commerce, or on vehicles that travel from virus-ridden areas.

For additional information on the avian influenza and efforts to combat it, see Bird Flu.

(The Washington File is a product of the Bureau of International Information Programs, U.S. Department of State. Web site: http://usinfo.state.gov)