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A Scourge of Childhood Reemerges as Polio Spreads in Western Africa

A spike in highly communicable cases in Nigeria sets back the global eradication vaccination effort



WHO/T. Moran

Despite a massive international effort to eradicate poliomyelitis, the disease is alive and well in some corners of the world. Several previously polio-free African countries have now become re-infected because of major outbreaks in northern Nigeria where, experts say, vaccine campaigns are flawed and failing. "There are not enough kids, particularly in the northern part of the country [getting vaccinated]…. In some areas, as much as 40 to 50 percent of the kids are missed in the vaccination campaign," says Oliver Rosenbauer, spokesperson for the World Health Organization's (WHO) Polio Eradication Initiative.

In 2008 there were 1,618 documented cases of polio worldwide, 788 (nearly 50 percent) of them in Nigeria. The culprit in Nigeria's recent outbreak is type 1 polio, the most virulent and fast spreading of the three polio strains. The virus has now spilled into Benin, Burkina Faso, Ghana, Niger, Mali and Togo (via infected travelers)—countries that had no reported cases in 2007, with the exception of Niger, which had 10.

"We consider one case to be an outbreak in a polio-free area," Rosenbauer says. This is because for every one person with an obvious case of polio (a virus that causes paralysis most commonly in children under five) there are some 200 "silent cases"—people who unwittingly become infected but never become paralyzed. Most people who contract the virus develop flu-like symptoms that clear up within days or weeks or they have no symptoms, but may still pass the disease to others. Polio is transmitted via the fecal-oral route: To catch the disease, a person must ingest the feces of an infected person. This happens relatively easily in areas with poor sanitation systems where drinking water is contaminated with sewage and human waste.

In 1988, 166 national governments (from the U.S., European Union and developing nations) joined forces with WHO, Rotary International, the U.S. Centers for Disease Control and Prevention (CDC), and UNICEF to launch the Global Polio Eradication Initiative—the largest worldwide coordinated public health endeavor ever created. Since that time, more than $5 billion from governments, Rotary International, WHO, and other organizations has been injected into vaccination campaigns around the world.

So why can't the disease be wiped out in Nigeria? "The main problem is that vaccination campaigns [there] are not sufficiently run and managed," Rosenbauer says, most notably in five northern Nigerian states (Kano, Katsina, Kaduna, Zamfara and Bauchi), where local governments are asleep at the switch. "The most important thing that we need is the full engagement of the political leadership. The district chief...[is] the person who can make things happen in his district … and to get [his] engagement state governors must be engaged."

What should local chiefs and state governors do? Robert Scott, a retired family physician and current chair of Rotary's PolioPlus Committee, says they should organize education programs for vaccine teams, educate parents on the importance of vaccinating children (by distributing pamphlets, airing TV spots and using other media to get the message out), and reassure people that the vaccine is safe. (Polio campaigns in Nigeria and other developing countries have been crippled by rumors that the vaccines cause sterility and AIDS.)

If history provides any guidance, there is no reason to believe northern Nigeria cannot run an effective polio vaccine campaign. At the end of 2007, the country had only 264 polio cases. Then, in 2008, it fell off the wagon, racking up 788 cases.

Despite the recent setback, worldwide efforts to stamp out polio have been "99.9 percent" effective, Scott says. When the Global Polio Eradication Initiative was launched, polio was endemic (thriving and prevalent) in 125 countries, paralyzing at least 1,000 children per day. Now the virus remains active in only four countries—Nigeria, India, Pakistan and Afghanistan—and paralyzes fewer than 2,000 children worldwide yearly.

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