When the worldwide campaign to eradicate polio was launched in 1988, the disease was circulating freely in 125 countries and some 350,000 people were infected. By the end of 2001, the circulation of the virus had been reduced to 10 developing countries and fewer than 500 cases.

Bob Keegan, acting director of the global immunization division at the Centers for Disease Control and Prevention in Atlanta, Georgia, says: "The global polio eradication initiative has reduced cases by more than 99%. And where in 1988 approximately 1000 children a day were paralyzed from polio virus, now we are looking at, this year, probably less than 1000 for the entire year."

Mr. Keegan says the goal of eliminating polio by 2002 was achieved throughout the Western world. (The last polio case in the United States was recorded in 1979.) But the disease continues to plague some developing countries in Asia and Africa.

"In 2003, we've had the largest number of polio cases reported from Nigeria," says Bob Keegan. "This is a dramatic change from previous years. In previous years, India was the number-one country for reporting polio cases. In fact, in some years they've had as much as 80 percent of the world's burden of polio in India. But this year India seems to have turned the corner and there has been a very sharp reduction in the number of cases from last year in India, and Nigeria is experiencing an epidemic, particularly in its northern states, so that Nigeria now has more cases than India and Nigeria is the number-one country in the world in terms of the number of polio cases being reported this year."

The polio virus lives in the intestines and is spread by contact with fecal material. This is a problem especially in countries with poor sanitation and a shortage of clean drinking water. The virus attacks nerves that control movement and causes paralysis. It usually afflicts children younger than five. In some cases, the disease is fatal and in rare cases patients recover. While polio cannot be cured, it can be prevented with vaccination. In 1988, four international groups - The World Health Organization, UNICEF, Rotary International and the Centers for Disease Control and Prevention - launched a global campaign to rid the world of the disease. Its success has been enormous, but not complete. Recently, polio has begun to spread from northern Nigeria to the neighboring countries of Togo, Burkina Faso, Ghana and Chad.

Dr. Mansur Kabir, Commisioner of Health in the northern Nigerian state of Kano, cites several reasons for the current polio epidemic in his state: "Kano state has a population of over 17 million people tightly packed in a very narrow area. Secondly, there is a lot of poverty in the society, and in addition to that our routine immunization has virtually collapsed. When we looked at our figures for polio routine immunization, we were able to cover maybe 10 to 15% of the children. So you can see that about 80% of our children go without immunization."

Dr. Kabir says the same ratio of children is at risk from other fatal diseases, such as malaria and whooping cough, due to poor nutrition and unsanitary living conditions. Infant mortality is extremely high in the State of Kano. A shortage of funds is the main reason many children escape routine vaccination.

"But I think another reason why we continue to have the wild polio virus is because we have a population that is not educated and that is skeptical about immunization,? says Dr. Kabir. ?A lot of rumors are going around and a lot of children have not been available for immunization because the parents don't believe it is good for their children."

Most of the population in northern Nigeria, including the states of Kano, Zamfara and Kaduna, is Muslim. Last month, when world organizations raced to immunize some 15 million African children at immediate risk of contracting the virus, some conservative Muslim families refused to have their children vaccinated. Rumors that the Western world is trying to wipe out Muslims through HIV infected vaccine, or vaccine that causes infertility, have compelled the Nigerian government to analyze the content of the serum to make sure it is safe.

Bob Keegan of the Centers for Disease Control in Atlanta says the same polio vaccine has been used in many Muslim countries: "This polio vaccine is well documented as being a safe vaccine. This same vaccine has been used successfully in many countries where the governments are Islamic governments. So the idea that this is somehow a vaccine which is unsafe in Muslim countries and intended to target Muslims in some way is just a false idea. And we have plenty of documentation of success stories in Muslim countries with this vaccine to show that."

Mr. Keegan says similar rumors among Muslim communities in India have been discounted and immunization has made much progress in the past year.

Nigerian Dr. Mansur Kabir says the support of religious and community leaders is crucial for the success of polio eradication in his country: "The Emir of Kano has been very supportive. He is a very modern person and his support has permeated down to the grassroots level," he says. "We have also recognized that the religious leadership too needs to be carried out in the process of getting our programs to be successful. Most of the ulama (religious leaders) have been involved in one way or another in getting our programs to be understood and ensuring that they do all the necessary advocacy for us to succeed."

Still, with 75 cases of polio, Kano has become the global epicenter of polio, putting possibly 15 million children at risk.

Dr. Kabir says eradication programs in such densely populated areas as Kano include training numerous personnel to administer house-to-house vaccination, take stool samples and collect data. Vaccinators may need local guides to reach remote rural areas. And they have to be able to educate people about the vaccine. They also have to dispel the rumors against vaccination.

Hajiya Maryam Musa Magaji, a Muslim woman from Kano is expecting a new baby: "I have allowed my previous children to be vaccinated. But now, because of the rumors I have been hearing about the vaccine, I'll not allow my next child to receive the vaccine."

Like most people in remote communities, she is wary of outsiders and accepts instructions only from her elders: "But if my husband says it is OK," she adds, "I will have my child vaccinated."

In such traditional communities, immunization campaigns are more successful if vaccinators are trained community members. Retired army nurse Ana Odey, central immunization facilitator for Kano's Kibiya district, says her program relies only on local staff:

"We take the inhabitants of this particular area to train them so that when they get into their different villages they will not be rejected. No one will say who are these strange people coming to immunize our children? It is their children, it is their sisters, it is their wives, it is their husbands doing the job."

Health officials say even though rumors have hampered immunization efforts and more funds are needed, they are confident that the world can be rid of polio by 2005.