By: Lois Parshley on May 22, 2013 GENEVA – In Dadaab, Kenya, the scrubland’s acacia trees stretch largely unbroken. In this dry northeastern part of the country, a refugee camp spreads over 50 kilometers, Home to more than 500,000 refugees, more than 1,000 people a day arrive here seeking shelter; in 2011, it became the largest refugee camp in the world. It’s here, deep in the Horn of Africa, that a four-month-old baby girl recently developed paralysis. Acute flaccid paralysis can be caused by many things, but World Health Organization officials have just confirmed the case is in fact caused by wild poliovirus. This is the first time in two years polio has been found in Kenya, and two people who’ve had contact with the girl have also tested positive. Polio is often asymptomatic – only one in 100 develop paralysis, which is often the diagnosing symptom – making controlling the spread of the disease difficult. Already, a second case of “wild” polio, as cases unrelated to vaccination are termed, has been confirmed in nearby Banadir, Somalia. Because of high levels of sustained conflict there are “large-scale population movements” in the region. This extensive refugee population makes any kind of routine immunization program or coordinated epidemic response extremely difficult, and WHO officials consider the risk of this polio outbreak spreading as “very high.” The last time there was a widespread polio outbreak in Africa was in 2008 and the entire Horn of Africa was affected, ultimately infecting over 700 people. WHO has already begun a vaccination campaign, and a second round is planned for May 26th. But as Dr. Ariel Pablos-Mendez, head of the Bureau of Global Health at USAID, explains, the main problem with implementation of effective health care is violence. Although Pablos-Mendez insists that the recent murders of WHO vaccinators in Pakistan is not “the main problem with immunization campaigns,” he admits to a “general lack of trust,” in addition to the practical problems of trying to reach a highly mobile population. It’s just these factors that have led to a low rate of vaccinations in the Horn. The WHO stresses, however, that emergency response have greatly reduced the duration and severity of polio outbreaks since 2006. After over $9 billion dollars have been spent to eradicate polio globally – a campaign that has been overwhelmingly successful – health officials are concerned about losing hard-fought gains in controlling the disease. There are economic arguments for this attention to polio; Bill Gates called having a strong global health system “the rich world’s enlightened self-interest,” and according to a study published in the Lancet, this investment has generated $27 billion of net benefits. But that also means there’s now a lot on the line, and critics, who thought that the money could have been better spent on more basic concerns, like sanitation efforts, may be vindicated if this outbreak can’t be controlled.