When Nigeria's northern state of Kano decided last year to stop a polio vaccination campaign, claiming the serum was contaminated, world health officials were caught by surprise. They are now drawing lessons to make sure that rumors and misinformation will never again scuttle a vital health campaign.

Late last year, Nigeria's Kano state halted its polio vaccination campaign after local Islamic leaders claimed the serum was contaminated as part of a plot to spread AIDS among Africa's Muslim population and to sterilize Muslim women.

The governor of Kano state, Ibrahim Shekarau, now says that following investigations he and other Kano officials have accepted the safety and effectiveness of a vaccine made by the Indonesian company Biopharma, and will resume the campaign.

But health officials say Africa has paid dearly for the ban. According to the World Health Organization, since the campaign was canceled polio has spread to at least 10 African countries that had previously been polio-free, and more than 250 Nigerian children have been diagnosed with polio - compared to 50 cases in the same period last year.

The officials are now reflecting on lessons drawn from Nigeria to make sure nothing like this happens again.

Speaking at a recent news conference, the deputy director for the U.N. children's agency, Kul Gautam, said, "Our first priority must be to build confidence and participation in immunization campaigns from the grassroots up. Unfortunately, the needless controversy around the use of polio vaccine in Nigeria has alarmed a lot of families in the region and we need to change that."

Health officials say rumors and misinformation can be stopped if a campaign is planned well in advance and all the relevant authorities are involved in making the necessary decisions.

One example comes from an animal health campaign run by a veterinary team under the U-S Army's Combined Joint Task Force-Horn of Africa. U.S. Army Major W. Brice Finney, who heads the team, said his group involved everyone in a rabies vaccination and livestock de-worming campaign in Kenya.

"What we have found is, it is very important to include everybody in the decision-making process, because usually those rumors get started because somebody was left out of the loop when the decision was being made," he said. "They felt compelled to maybe undermine the effort a little bit."

Major Finney says he and his team held many meetings with members of Kenya's parliament, provincial and local government officials, doctors, community leaders and elders, and others to prepare for the event.

When the U.N. children's agency, UNICEF, vaccinated more than two-million children against measles last month in the war-torn western Sudan region of Darfur, the organization used about 2,000 small mobilization teams from the region's state governments to encourage parents to have their children immunized.

UNICEF's spokeswoman in the Khartoum office, Paula Claycombe, says in vaccination campaigns, it is usually a country's health ministry that is responsible for informing the public about vaccines and what they are designed to do.

She says the Darfur region's state governments were successful in persuading internally displaced people to have their children vaccinated.

"The state ministries of health and education and the national water corporation are in many instances comprised of individuals who come from the same groups and villages as the populations that have been displaced," she said. "So, they see it very much in their own interests, in their communities' interests to provide the immunization services."

She says measles vaccination campaigns will continue in Darfur throughout the summer. Children under five will also be vaccinated against polio, which spread into Darfur from Nigeria.