NAIROBI, Kenya—Nigerian authorities on Friday battled Africa's first known outbreak of deadly bird flu as experts warned that the virus already could have spread through farms in the country's rural north.
Health officials said they had quarantined large commercial poultry farms and had begun slaughtering poultry in three northern states where birds had been infected with the H5N1 virus, which can be lethal to humans.
They also bulldozed the ashes of 45,000 cremated chickens from a farm in Kaduna state, where the first outbreak was announced Wednesday.
No human cases have been reported in Nigeria. On Friday, two deaths were reported in China and Indonesia, adding to the 88 worldwide deaths previously confirmed by the World Health Organization since 2003.
With the virus having moved south from Europe and the Middle East in recent weeks, experts were closely watching developments in Nigeria, Africa's most populous country and a test for the continent's weak, underfunded public-health systems.
As it is in many African countries, poultry farming is a major industry in Nigeria and millions of people raise chickens in their backyards.
The virus can jump from birds to humans though close contact. If it mutates into a form that passes easily among humans, scientists fear that it could spark a global pandemic.
While Nigeria's response has won praise so far, experts were worried by news reports that tens of thousands of chickens had died mysteriously on large and small farms across northern Nigeria over the past month.
Boubar Seck, the West Africa bird-flu coordinator for the U.N. Food and Agriculture Organization, said that suggested that containment efforts might be too late.
The announcement Wednesday by the World Organization for Animal Health that the virus had landed in Nigeria came as the result of tests on birds that fell sick beginning Jan. 10.
It took that long for the samples to arrive at a laboratory in Italy and be analyzed. Meanwhile, Seck said, the virus probably was spreading.
"We lost about three weeks," Seck said. "That's one of Africa's problems: We don't have the facilities. So while we were waiting, we don't know what was happening with the virus."
The Food and Agriculture Organization said Nigeria's neighboring countries should increase surveillance at their borders to keep out imported poultry. It called on Nigerian authorities to stop the movement of poultry and to close poultry markets in the affected states.
That's a major challenge in a country with a poultry population of 140 million, mostly free-ranging, according to Food and Agriculture Organization estimates.
The Nigerian government has launched a campaign to educate citizens about the virus and has offered farmers compensation for livestock losses. But some experts said that wouldn't persuade small-scale farmers—for whom chickens often are the only sources of income—to report sick birds immediately.
"On commercial farms the government compensation makes it easier to sacrifice birds," said E.B. Sonaiya, the president of the Nigerian branch of the World Poultry Science Association. "But the real problem is with free-ranging birds. They are all over."
Teams of experts from the World Health Organization and other international agencies have begun arriving to assist with the response. The United States has pledged $20 million in emergency aid, and the Food and Agriculture Organization and the U.S. Department of Agriculture have promised to send more than 1,000 sets of protective gear.
(c) 2006, Knight Ridder/Tribune Information Services.
GRAPHICS (from KRT Graphics, 202-383-6064): 20060209 AVIANFLU spread, 20060210 Nigeria update
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