(Associated Press) – Zimbabwe began an emergency campaign to inoculate more than 4 million children against polio on Tuesday after health authorities detected three cases caused by the rare mutation of the weakened virus used in oral vaccines, including a 10-year-old girl who was paralyzed in January.

The health ministry said laboratory tests from samples collected from sewage sites in several areas of the capital, Harare, late last year showed the presence of a mutated polio virus that originated in an oral vaccine used in the global eradication effort. (Read More)