Jan 27, 2004 (CIDRAP News) – China reported an outbreak of highly pathogenic avian influenza in ducks today, while the World Health Organization (WHO) joined other international groups in appealing for a multinational campaign to stop the disease's march across Asia.
Meanwhile, Thailand reported its second death caused by the influenza A(H5N1) virus. The victim was a 6-year-old boy. Ten human cases of H5N1 infection have been confirmed—seven in Vietnam and three in Thailand—and eight of the patients have died.
Also, Dr. Julie Gerberding, director of the US Centers for Disease Control and Prevention (CDC), said the risk of avian flu in the United States is very low, but the CDC is stockpiling drugs that could help prevent and treat the illness in humans, among other precautions.
So far the WHO has recognized H5N1 outbreaks in poultry in Vietnam, Thailand, South Korea, Japan, and Cambodia, the agency's Western Pacific office said today. But outbreaks of the same virus have been reported by governments or other sources in Indonesia, Laos, and now China. Taiwan and Pakistan have reported poultry outbreaks of weaker avian flu viruses.
Xinhua, China's state news agency, reported an outbreak of H5N1 avian flu on a duck farm in Guangxi Zhuang Autonomous Region in south-central China. Local officials destroyed 14,000 birds on farms within 3 kilometers of the affected farm on Jan 23 and quarantined all poultry within 5 kilometers, the report said. The Associated Press (AP) said the farm is about 60 miles from the Vietnamese border.
China's national reference laboratory for avian flu confirmed H5N1 virus in duck samples from the farm, Xinhua reported. The story said China has launched "nationwide preventive and control efforts" and informed the WHO and the United Nations Food and Agriculture Organization (FAO) of the outbreak. The response appeared to contrast sharply with China's secretive approach in the early months of the SARS (severe acute respiratory syndrome) epidemic there in late 2002 and early 2003.
In a joint statement today, the WHO, FAO, and OIE (World Organization for Animal Health) said the world has a chance to stave off a "human and animal pandemic" of avian flu. "We have a brief window of opportunity before us to eliminate that threat," said Dr. Jacques Diouf, FAO director-general.
The three agencies appealed for donors to provide funds and technical help to countries fighting the disease, which the statement called "a threat to human health and a disaster for agricultural production."
The groups said affected countries urgently need to kill infected and exposed animals and tightly control animal movement in affected areas. Those measures, along with compensation for farmers, will be hugely costly, officials said.
WHO Director-General Dr. Lee Jong-wook said, "We face something we can possibly control before it reaches global proportions if we work cooperatively and share needed resources. We must begin this hard, costly work now."
The WHO is trying to develop a human vaccine for the disease, but Shigeru Omi, director of the WHO's Western Pacific Region, said today that will probably take at least 6 or 7 months.
In a news briefing today, the CDC's Gerberding said an avian flu problem in the United States seems very unlikely, "but we want to be very vigilant."
The CDC has six scientists helping to investigate the widespread outbreak in Vietnam and is working with the WHO to develop a seed virus strain that could be used to make a vaccine, Gerberding said.
Earlier this winter, the CDC began stockpiling the antiviral drug oseltamivir for possible use against the ordinary human influenza A(H3N2), Gerberding said. "That proved to be a very prescient recommendation," she added. "We're in the process of acquiring a significant stockpile of drugs." WHO officials recently said tests indicated that oseltamivir could be effective against H5N1 infection, though two older antiviral drugs are not.
The CDC is not warning people against travel to countries affected by avian flu now, but travelers in those areas should avoid poultry farms, live animal markets, and surfaces contaminated with waste from infected birds, Gerberding said.
She also said clinicians should take a careful travel history from patients with flu-like illness, and patients who have such an illness should tell their physician if they traveled to affected countries.
Given the number of human cases and other evidence so far, Gerberding said it appears that the avian flu is not being transmitted efficiently from birds to humans and is not spreading from person to person at all.
Contrary to some reports, she said, "Pigs have not yet been identified as being sick [with the H5N1 virus], but we are working with other investigators to evaluate pigs on farms, especially those that have birds." Pigs are thought to have played a role in past flu pandemics by providing a vessel where avian flu viruses combined with other flu viruses to spawn dangerous new strains.
Gerberding also said the federal government has taken steps to stop the importation of birds that could be carrying the flu virus from affected countries. Exotic birds are normally quarantined at ports of entry for a time before they can be brought into the country, she added.
She said there is reason to hope that the avian flu can be contained. "It's important to remember that China did in fact contain SARS, and that was also a very, very challenging public health situation," she said. "I don't think we should be pessimistic, we should be realistic about the challenges."
Call for international assistance by FAO, OIE, and WHO
WHO's Jan 27 update on avian influenza