Lagos - The World Health Organisation said it aimed to vaccinate 63 million children in West Africa in a new campaign against the crippling polio virus, in spite of opposition from Muslim leaders in Nigeria.
Some Islamic elders in northern Nigeria have opposed vaccination because they believe the vaccines being used are tainted with infertility agents.
The WHO said the failure of northern Nigeria, and particularly Kano state, to join earlier vaccination efforts had helped spread polio across West Africa over the last few months, and turned Nigeria into a breeding ground for the virus.
"Polio has again spread across West and Central Africa, paralysing children in seven previously polio-free countries," the WHO said in a statement.
The WHO said the opposition to vaccination in Nigeria threatened its goal of eradicating polio globally by 2005.
"The whole continent is on the brink of re-infection unless these campaigns stop the further spread of the virus," said the WHO's Africa director, Ebrahim Samba.
The latest vaccination campaign, due to start on Monday, aims to cover 63 million children in 10 countries.
Three weeks ago, the Nigerian government said it would subject the vaccine to tests abroad in the hope of resolving the dispute. A health ministry spokesperson said on Friday the results had not yet come back.
Datti Ahmed, chairperson of Nigeria's supreme council for sharia (Islamic law), said he would maintain his opposition until it was shown that the vaccine was safe.
He said an earlier test commissioned by a Nigerian Islamic group had revealed traces of infertility agents, which he said were part of a Western plot to depopulate the region.
"We are not objecting to immunisation per se, but we object to vaccines that hurt people," he said. "Our advice is to discard the adulterated vaccines and bring in new ones that are not adulterated."
The WHO said concerns about the vaccine were unfounded. Since 1996 its "Kick polio out of Africa" campaign has reduced polio cases from 205 daily in the continent to 388 during the whole year in 2003.
The introduction of Islamic sharia law in 12 northern, predominantly Muslim states in 2000 has deepened religious divisions in the country. About 10 000 people have died in religious and ethnic violence since the return of democracy in 1999.