Poliomyelitis vaccines. Success and controversy.

The conquest of poliomyelitis by killed and live poliomyelitis vaccines is arguably the most successful American public health project. In 1950, 20,000 cases of paralytic poliomyelitis were reported in the United States, whereas in recent years, fewer than 10 cases were reported. These few cases were largely associated with oral vaccine and despite their small number have led to a reconsideration of killed vaccine as a public health measure in the United States.