The deadly H5N1 bird flu virus has been detected on a large commercial chicken farm in Nigeria — the first reported outbreak in Africa, the World Organization for Animal Health said Wednesday.

The outbreak appears to be restricted to birds, and no human infections have been reported, the Paris-based organization said.

Nigeria said the outbreak was on a farm in Jaji, a village in the northern state of Kaduna. Agriculture Minister Adamu Bello told reporters in Abuja that the deadly strain of the virus was detected in samples taken Jan. 16 from birds on the farm.

"We are dealing with a new continent," said Alex Thiermann, an expert for the World Organization for Animal Health, known as the OIE, told The Associated Press.

Bird flu began ravaging poultry stocks across Asia in 2003, forcing the slaughter of more than 100 million birds and jumping to humans. The World Health Organization has confirmed 88 deaths from bird flu out of a total of 165 cases of human infection. Almost all the cases have been in Asia, but the disease recently has been detected in Europe and the Middle East.

Though all the people who contracted the disease so far are believed to have been infected through contact with sick birds, experts are concerned the disease could mutate into a form easily spread from human to human, potentially triggering a global pandemic.

Experts have long been concerned about Africa's ability to deal with a bird flu outbreak. Thiermann noted that some African countries have "very weak" veterinary systems.

Thiermann said all 46,000 birds on the Nigerian farm have been killed and their bodies disposed of, and Nigerian authorities have banned the movement of birds and people from the farm. Officials also are investigating whether birds were transferred to other farms in the past 21 days, and they, too, are being quarantined, he said.

"We feel that they are doing everything they can and they certainly need help," he said.

Additional protective clothing was being moved Wednesday from Senegal to Nigeria, he said.

Experts had suspected that migrating wild birds could spread the disease to Africa, said Thiermann, noting that Nigeria is on a "major flyway."

A laboratory in Padua, Italy, identified the H5N1 strain in the Nigerian birds, OIE said in a statement. It added further tests were being carried out to determine how closely the Nigerian strain matched the H5N1 strain detected elsewhere in the world.

The Italian Health Ministry said the bird flu strain is very similar to those found in Siberia and Mongolia.

The OIE said it was working with the U.N.'s Food and Agriculture Organization to "coordinate a common response to this event."

A team of experts to assess and provide technical advice will leave for Nigeria toward the end of this week, said Thiermann, who is a special adviser to the OIE's director.

Health officials had feared a deadly bird flu virus could enter impoverished, loosely governed African regions, where many people raise chickens at home for personal consumption.

Nigerian officials said Wednesday that initial tests on chickens that mysteriously died in Kano, a state neighboring Kaduna, showed no signs of bird flu. Salihu Jibrin, head of the state's livestock department said at least 60,000 birds have died in Kano state in recent weeks. Tests were ongoing.

Nigerian authorities nevertheless urged farmers to monitor their flocks and report strange ailments to authorities. Kano set up a committee of veterinary surgeons to visit farms and watch out for evidence of a bird flu outbreak after some poultry farms reported large-scale bird deaths last week.

Large-scale poultry farms aside, many Nigerian families live in close quarters with chickens and other fowl, which are an important food source. The birds generally are kept with other domestic animals at night but are allowed to roam freely during the day.

Controlling the spread of the virus could be particularly difficult in Africa, where central governments often exert little control in far-flung rural areas most likely to have people keeping fowl in their homes.