Polio reappears in Nigeria, triggering massive response

Setback comes 2 years after last reported case

A child receives polio vaccine during a 2013 vaccination campaign in Nigeria. ZUMA Press Inc./Alamy Stock Photo

The government of Nigeria today launched a massive vaccination campaign in the northern state of Borno in response to news that two children there had been paralyzed by wild-type polio virus. The cases, reported last week, came just as Nigeria and the global community were celebrating 2 years without a wild polio case in a country that once accounted for half of all cases in the world. Now, Nigeria's neighbors are also preparing major polio vaccination efforts in a bid to prevent new cases.

The new outbreak didn't come as much of a surprise to those who have long been trying to eradicate the virus. Much of Borno is under control of the ruthless terrorist group Boko Haram, vaccinators have been unable to reach hundreds of thousands of children, and the insurgency has disrupted surveillance for the virus, which appears to have been circulating undetected for years. "This is what keeps people in polio eradication up at night—the worry that polio virus could be lurking in the insecure parts of Borno and Somalia," says Steve Cochi, the point person for polio eradication at the U.S. Centers for Disease Control and Prevention (CDC) in Atlanta.

 Cochi also mentions another factor: complacency. With Nigeria off the list of endemic countries—only Afghanistan and Pakistan remain—eradication leaders have been optimistic they would stop transmission worldwide in 2016, bringing them tantalizingly close to the end of the 28-year $14 billion eradication effort. But there were signs that, after its hard-won success, the government of Nigeria was letting down its guard. "It is not surprising that attention would slip after 2 years without a case," says Michel Zaffran, the new director of polio eradication at World Health Organization (WHO) headquarters in Geneva, Switzerland. "You lose political commitment very quickly when a disease appears to have disappeared," Cochi agrees. 

A 4-and-a-half-year-old girl named Aisha in Jere district was the first new case. In May her extended family had escaped from Boko Haram–controlled territory and trekked 2 days to the Muna camp for internally displaced persons in Jere, according to Zaffran. The girl, who became paralyzed on 6 July, has since recovered "and now walks without a limp," he says. Health officials, under military escort, are still investigating the second case, a 12-month-old boy who was paralyzed on 13 July in Gwoza district, not far from Chibok where Boko Haram abducted more than 200 schoolgirls in 2014.

CDC scientists quickly sequenced viral isolates from the two cases. Both viruses are closely related to one last seen in Borno in 2011, suggesting that polio has been circulating undetected there for 5 years. Cochi and others fear the virus has spread widely throughout the countries of the Lake Chad region. "The borders are all insecure," he says.

Because of the 2-year respite, many of the government experts who led the battle to wipe out the virus in Nigeria have moved on. "New people will have to come to grips with the problem," says Muhammad Pate, the former minister of state for health who headed the country's polio effort and is now an adjunct professor at Duke University in Durham, North Carolina. The presidential task force on polio eradication Pate used to chair hasn't convened in at least a year. Although the central government has budgeted money for polio eradication this year, officials have not yet released it, and interest among some local government officials is waning.

Pate worries that people will attribute the outbreak to insecurity alone and "might miss the significance of this as a wake-up call to be more diligent when there are no cases." That means making sure that each campaign is meticulously executed, monitoring every vaccinator, and using real-time data from one vaccination round to plan the next.

More campaigns are in the works. A second one is scheduled to launch 27 August across four northern states, with the goal of reaching 4 million to 4.5 million children under 5. Chad, northern Cameroon, southern Niger, and parts of the Central African Republic will synchronize campaigns. Already helicopters are flying vaccine into hard-to-access areas like Gwoza, and "the next step is to airlift vaccinators because the road is not safe," says Alhaji Samaila Muhammad Mera, the emir of Argungu in Kebbi state and the deputy chairman of the Northern Traditional Leaders Committee on Primary Health Care. Teams are searching for more polio cases in Jere and Gwoza. And in one bit of good news, the military recently wrested control of large swaths of Borno from the insurgents, which may enable vaccinators to reach what were previously "no-go" zones.

Traditional and religious leaders, who have been pivotal in convincing suspicious populations to accept polio vaccination, are mobilizing quickly, Mera says. Because the camp where the girl was diagnosed is close to Maiduguri, Borno's densely populated capital, "we need to do something there very quickly," Mera says. "There is so much at risk."

WHO's Zaffran says the speed and magnitude of the response bodes well for quashing the outbreak quickly. "I personally believe we can still interrupt transmission worldwide in 2016, and we are certainly doing everything possible to do so."

Bruce Aylward, the longtime leader of the global initiative who more recently ran WHO's Ebola response, says program leaders should be ready for more setbacks. "You are dealing with the tail end of a huge eradication effort … this is when the virus will do everything to depress, demoralize, and derail you," he says. "Are we as committed to its extinction as it is to surviving?"

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