Lagos — The World Health Organisation (WHO) said yesterday that initial tests on samples from 14 Nigerians, including three people who died, showed they were not victims of bird flu.

In Geneva, a WHO official said all 14 samples had tested negative for the H5 strain of flu but positive for another type. Samples from the 14 would be sent to a reference laboratory in London for more checks, said David Olaleye, a WHO doctor taking part in the testing at a laboratory in Abuja.

"We have done two rounds of tests over the weekend and those were negative ... Today we are re-running another round of tests and I am waiting for the results," Olaleye said.

He added that arrangements had been made to transport the samples to the London laboratory today.

Samples have been taken from three people who died of unknown causes and 11 people who came into contact with them.

The H5N1 bird flu virus remains primarily an animal disease but can kill people who have close contact with infected birds.

It has killed 163 people around the globe since 2003 and experts fear it could spark a pandemic in which millions could die if it mutates into a form that passes easily from person to person.

The samples include ones from a mother and daughter who died in Lagos and from a woman who died in remote eastern Taraba state after suffering flu-like symptoms.

Nigeri was the first on the continent to detect bird flu a year ago. The virus has spread to 17 of the 36 states but no human case has been confirmed.

Experts warn surveillance in Nigeria may not be completely effective because of poor health services. Nigeria is one of three countries regarded by experts as the weakest areas in the global attempt to stem infections of birds.

The disease was first discovered in the northern state of Kaduna a year ago and despite measures such as culling, quarantine and a transport ban on live birds it spread quickly across the country.