On Tuesday, a new polio vaccine was used for the first time in Afghanistan, one of only four countries in which the disease still lingers. (Neighboring Pakistan, Nigeria and India are the others.)
Although it has been 50 years since the United States developed a vaccination for polio, millions of children remain unprotected. Polio is an infectious disease carried by the poliovirus. It causes motor paralysis and atrophy of skeletal muscles, often causing permanent disability and deformity.
Over the three-day immunization campaign, the World Health Organization said it hopes to immunize nearly 3 million children under age 5 in parts of Afghanistan, especially the southern regions. In some areas of the Kandahar and Helmand provinces, more than 60 percent of children have yet to be immunized, according to the WHO. Most of Afghanistan is polio-free, but 31 children have been paralyzed by the disease this year so far.
The new vaccine, given by oral drops, combines the protection from the two remaining types of polio into one dose.
Access to vaccines is one of the most basic, and biggest, problems in fighting the disease. And in some countries, distrust of the government and vaccines hinders vaccinating children against polio.