Aug 24, 2004 (CIDRAP News) – Chinese health officials confirmed yesterday that H5N1 avian influenza had been found in pigs there in 2003 but says no such findings have occurred in 2004. They also stated that the occurrence had been made public earlier in the year, although the UN Food and Agriculture Organization (FAO) says there has been no official report of the disease in pigs.
The Chinese ministry of agriculture in a press release stated that, spurred by the widespread outbreaks of avian flu in Asia earlier this year, they have tested 1.1 million samples from poultry and some samples from pigs and that no H5N1 has been found in pigs, Chinese news agency Xinhau reported. The agency said also that the 2003 finding of the virus in pigs had been made public earlier this year. It turns out that an article reporting the findings appeared in the January issue of the Chinese Journal of Preventive Veterinary Science and another in the May issue. The latterreported that the virus was found in April 2003 in pigs at four locations near the east coast of China. The articles are in Chinese; translation for FAO and the World Health Organization (WHO) is under way.
Confusion began when a prominent Chinese avian influenza expert, Chen Hualan, an author of the two studies, said in a presentation at an international meeting late last week that the H5N1 virus had been found in pigs in China in both 2003 and 2004, to the surprise of WHO and FAO officials who were not aware of this. A New York Times story says a press official of the Chinese health ministry was likewise surprised when told later of the expert's comments and that he said his office had no information on the subject. It is unclear whether Chen's remarks had been officially authorized.
The state-run Beijing Times ran a story today saying that Chen, after several days of silence, called the amount of avian flu virus in the pigs "extremely small," with the probability of isolating H5N1 from the animals "less than one in a thousand," according to an AFP story. The story also stated that an unnamed spokesperson for the ministry of agriculture said "some experts' remarks" were at odds with the government's view of events.
FAO official Juan Lubroth said several details about the cases in pigs, including whether the animals in which H5N1 was found became sick, are crucial, the New York Times story says. If the pigs did not become ill, he explained, they would be harder to detect and quarantine or destroy, although this might also indicate that the virus had lost some of its potency. The WHO in a statement on its Web site points out the importance of comparing the H5N1 isolated from pigs with the strain isolated from poultry to determine whether the virus was passed directly from poultry to pigs. Shigeru Omi, WHO regional director for the Western Pacific, told AFP that "We have asked [Chinese officials] for information, but so far there have been no additional details. Overall the Chinese government has been cooperative and I hope they will remain so."
In other developments, the state-run Thai News Agency reported the August death of a dozen pigs in a northern province, according to a Xinhau story. The animals reportedly had symptoms of coughing, breathing difficulty, and swelling eyes. Chickens on the same farm had died earlier of avian flu, the story says. This report has not been confirmed.
In Malaysia, the recent outbreak of avian flu in poultry appears to be restricted to the small village in the northern state of Kelantan where it was confirmed last week, according to the health ministry there. Testing of birds within a 6-mile radius of the village continues, however, and all humans newly suspected of having the disease, including a veterinarian and her three children, have been cleared, according to Reuters. The European Union extended its ban on bird products from several other Asian nations to include Malaysia yesterday, however, and said its ban will stay in force through at least Dec 15, an EU Business story says. Malaysia has been commended by WHO for its prompt action in containing the outbreak.
In Viet Nam, 10 of the 11 provinces with re-emergent avian influenza earlier this summer have been free of any new outbreak for 21 days, allowing them to declare themselves free of the disease, according to the Vietnam News Agency. The country will continue to inspect imports and exports of poultry and poultry products and will inspect poultry breeding farms near earlier outbreaks.
WHO Aug 20 statement on avian flu in China