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Multiple Polio Outbreaks Threaten Beyond
Nigeria Experts worry that jump in cases could easily spread to other countries By Maria Chengap (Associated Press) LONDON (AP)- Polio cases in Nigeria have nearly doubled this year as officials struggle to fight various natural strains of the virus and those unleashed by the vaccine. Outbreaks linked to the vaccine, as opposed to the "wild," or naturally occurring, polio virus, are usually stamped out within months. But in Nigeria, the outbreak caused by the vaccine has been ongoing since 2005. Low immunization rates, a weak health system and vaccine rumors have fueled a worrying spike in the numbers of paralyzed children. Some experts worry the sudden jump in polio cases could complicate eradication efforts. Last year at this time, Nigeria had 54 reported cases caused by wild polio virus. This year, there have been 106 recorded cases so far, according to new figures released by the World Health Organization. "This is a huge step backwards," said Oyewale Tomori, a polio expert a Redeemer’s University in Nigeria. He said the last time the country had every type of polio was in 1999 and described the current situation as "hugely traumatic." Since acknowledging last year that some Nigerian children were paralyzed by a mutated virus from the oral polio vaccine, health officials have had to use three different vaccines to control the viruses. The vaccine-sparked outbreak has struck more than 100 children so far, including eight this year. For every paralyzed child, about 1,000 others are infected and spreading the highly infectious and sometimes fatal disease. Such outbreaks happen only when immunization rates are low. The oral polio vaccine contains a weakened virus. In rare instances, as the virus passes through children who have not been immunized, it changes into a form dangerous enough to ignite new outbreaks. An injectable polio vaccine is used in the West that does not cause outbreaks, but it is more expensive and must be given by a doctor or nurse "There are just way too many kids in Nigeria who haven’t been vaccinated, and that’s allowing the virus to spread," said Dr. Bruce Aylward, director of WHO’s polio department. Ending the country’s parallel polio outbreaks simply requires more vaccine. Nearly all of the children paralyzed by polio are in northern Nigeria, where a year-long boycott of the vaccine in 2003 triggered an explosion of the disease, which was exported to more than two dozen countries worldwide. Hard-line Nigerian Islamic clerics called for the boycott, claiming that an immunization campaign was part of a U.S.-led plot to render Nigerian Muslims infertile or infect them with AIDS. While Nigerian authorities formally reversed the vaccine boycott, the health system remains weak and there are lingering fears that the vaccine is a Western plot to sterilize Muslims. Up to 30 percent of children in the north have never had a single dose of polio vaccine, according to WHO. When doctors attempt to eradicate a disease, more than 90 percent of a population must be immunized, and each child in Nigeria needs about four doses of polio vaccine to be protected. "Our main problem is operational," Aylward said. "Most kids just lie beyond the reach of the Health Ministry." Countries with little or no polio also may take a medical gamble by deciding to spend their money elsewhere. "As countries slip back on their polio vaccination, they become ripe for outbreaks," said Dr. Neal Halsey, a polio and vaccine expert at the Johns Hopkins Bloomberg School of Public Health. Officials say that the large numbers of unvaccinated children in Nigeria make the entire world vulnerable to polio. While much progress has been made in the other three countries where polio is endemic - Afghanistan, Pakistan, and India - the surge in cases in Nigeria could undo all of that. "The outbreak in Nigeria is a shared global problem," Aylward said. "Until it is stopped in Nigeria, we are all at risk."
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