Cameroon on Sunday became the fourth country in Africa to report an outbreak of H5N1 bird flu after the virus was found on a duck farm in its northernmost province.

"The first case of bird flu has been detected in the Far North province," the government said in a statement.

Nigeria, Egypt and Niger have already reported cases of the highly pathogenic H5N1 avian flu strain in poultry flocks.

Cameroon Livestock Minister Sarki Aboubakary told Reuters the Pasteur Institute in Paris had identified H5N1 in samples taken from ducks which had died on a farm in the northern town of Maroua.

"Yesterday, we received confirmation from Paris that one of the samples was positive, that a case of H5N1 was effectively detected in one of the ducks," he said.

Cameroon´s Far North province borders Nigeria, where Africa´s first H5N1 bird flu outbreak was confirmed on Feb. 8.

No human cases have been discovered in Africa so far, but several Nigerians have been tested.

Aboubakary said Cameroon health authorities had slaughtered all the remaining ducks on the Maroua farm, closed down all poultry markets in the region and put the country´s veterinary services on a state of red alert.

Tests were being carried out on poultry in other farms in Far North province, and the government was preparing to vaccinate poultry if necessary, he added.

As the disease spreads in Africa, international experts are concerned that the world´s poorest continent, already battling HIV/AIDS and malaria, is ill-equipped in terms of expertise and resources to combat this new health threat.

Cameroon, along with other states sharing borders with Nigeria, has already banned all imports of poultry and poultry products from its neighbour.