A strain of bird flu virus that is not lethal to humans has killed at least 4,500 chickens in Vietnam, three months after an outbreak of the deadly H5N1 type that killed 16 people was declared over, officials said.
The chickens on three farms in the Mekong Delta province of Bac Lieu died or were destroyed after testing positive for the H5 strain of the bird flu disease. While the H5 type is not known to be harmful to humans, another strain, H5N1, is lethal.
“We are doing everything we can to contain the outbreak. Our hope is that it will not spread,” a spokesman for the animal health authority in Vinh Loi district where the three farms are situated said on Wednesday.
“All random tests on the chickens in these farms were positive for avian influenza of the H5 strain,” he added.
Anton Rychener, Vietnam representative for the U.N.’s Food and Agriculture Organisation, said news of the outbreak was not surprising.
“We have said all along the virus is really still out there and may periodically resurface,” he told Reuters. The FAO was in daily contact with Vietnam’s animal health department and the latest outbreak “is nothing to panic about,” he added.
Not dangerous to humans so far
Last week, Nguyen Van Thong, deputy director of the Agriculture Ministry’s animal health department, told Reuters many of the more than 10,000 poultry blood samples tested recently were H5 positive.
“So far the virus is not dangerous to human health but it is a present threat...all poultry should be inspected before consumption,” Thong said.
He said the tests were done on samples from 37 cities and provinces around the country and that most of the positive results came from water fowl like ducks.
Chinese and U.S. researchers reported on Monday that the frightening H5N1 strain of bird flu is mutating into an ever more deadly form in ducks and needs to be controlled quickly.
A small outbreak of the H5N1 virus was found in a farm in the south of the country in May but was quickly contained, state media had reported.
Birdflu erupted across many parts of Asia from late last year and killed millions of chickens and devastated poultry industries in several countries. It also killed eight people in Thailand.
Vietnam declared itself free of the disease on March 30.
People who got infected are believed to have caught the disease from close contact with sick birds. There were no confirmed cases of human-to-human transmissions.