A young boy rests by empty USAID vegetable oil tins in the Dagahaley refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. The refugee camp at Dadaab, located close to the Kenyan border with Somalia, was originally designed in the early 1990s to accommodate 90,000 people but the UN estimates over 4 times as many reside there. The ongoing civil war in Somalia and the worst drought to affect the Horn of Africa in six decades has resulted in an estimated 12 million people whose lives are threatened. (Photo by Oli Scarff/Getty Images)

A woman rests on a hospital bed in a ward adjacent to the Ifo refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. (Photo by Oli Scarff/Getty Images)

Refugees stand at the razor-wire fence of the Dagahaley refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. (Photo by Oli Scarff/Getty Images)

A girl looks out of her makeshift hut on the outskirts in the Dagahaley refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. (Photo by Oli Scarff/Getty Images)

A woman walks with a baby on the outskirts in the Dagahaley refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. (Photo by Oli Scarff/Getty Images)

A child waits in the registration area of the Ifo refugee camp which makes up part of the giant Dadaab refugee settlement on July 19, 2011 in Dadaab, Kenya. (Photo by Oli Scarff/Getty Images)