South Asia slashes polio cases by nearly half.
D000346:Afghanistan / Q000453:epidemiology; D002648:Child; D006801:Humans; D017589:Immunization Programs; D007194:India / Q000453:epidemiology; D010154:Pakistan / Q000453:epidemiology; D011051:Poliomyelitis / Q000453:epidemiology / Q000517:prevention & control*; D011159:Population Surveillance; D014944:World Health Organization