The World Health Organization has spent $5 billion over the last 20 years to immunize more than two billion children around the world against polio. Yet the deadly and crippling disease still poses a risk in four countries: Afghanistan, Pakistan, India and Nigeria, with Nigeria accounting for more than 50 percent of new cases.
VOA's Brian Padden recently visited the northern Nigerian state of Kano where polio is common and officials struggle to convince the local population to immunize their children.
Sudan's governemnt has accused Darfur's largest refugee camp of harbouring rebel fighters. The Kalma camp is the only one that is permanently protected by United Nations and African Union forces, but residents fear they may be driven out as the military threatens to take action. Al Jazeera's Hoda Abdel-Hamid reports from the camp.