How Common Is Infection With Poliomyelitis Virus?
At one time, poliomyelitis virus infection occurred throughout the world. Transmission of wild poliomyelitis virus was interrupted in the United States in 1979, or possibly earlier. An eradication program conducted by the Pan American Health Organization led to elimination of poliomyelitis in the Western Hemisphere in 1991.
The Global Polio Eradication Program has dramatically reduced poliomyelitis virus transmission throughout the world. In 2003, only 784 confirmed cases of poliomyelitis were reported globally, and poliomyelitis was endemic in six countries.