By Orin Gordon
BBC Africa Live!
The World Health Organisation (WHO) is trying to reassure African countries where polio cases have reappeared, that the vaccines to eradicate the disease are safe to take.
Religious leaders are yet to be convinced over vaccine safety
The organisation's special representative for Polio Eradication, Dr David Heyman said they are working at the state level to help traditional and religious leaders understand the importance of vaccination.
"We're trying to help them understand that these vaccines are safe, and that other countries throughout Africa have used them and have had success in getting rid of a disease that causes permanent disability in children," Dr David Heyman told the BBC Africa Live! programme.
Muslim clerics in northern Nigeria view the polio vaccines with suspicion.
They stopped the immunisation programme in three states last year saying the vaccines were contaminated with contraceptives.
Efforts to reassure them have been frustrated by conflicting laboratory test results on the disputed vaccines.
While the federal government's tests have given the vaccines the all-clear, northern leaders say that their own test results showed traces of the female hormone, oestrogen, in the vaccines.
WHO said it had gone to great lengths to prove to local leaders that the vaccines are safe.
Since the Nigerian Muslim clerics' campaign against the vaccine, polio has reappeared there and spread to neighbouring countries.
Officially polio is present in six countries: Nigeria, Niger and Egypt in Africa, and Pakistan, India and Afghanistan.
Egypt and India may soon be declared free of polio. But the WHO says that the disease has reappeared in the past few months in Ghana, Burkina Faso, Chad, Togo, Benin and Cameroon.
Ghana's health minister has already told the WHO that it has had to budget $1m to fight polio in a country that had been declared free of the disease.
They believe the new cases have been spread from Nigeria.
Dr Heyman admits it is hard work convincing the local government officials in the African countries affected.
"We are very concerned that these leaders are convinced that these vaccines are safe," he said.
"The manufacturers of these vaccines have all written to the governors of these states indicating that the vaccines are safe and giving them the evidence of this."
Nigeria's health minister, Professor Eyitayo Lambo told the BBC that the national immunisation campaign would restart next month and would cover all of Nigeria's northern states.