Epidemiology
While now rare in the Western world, polio is still endemic to South Asia, particularly Pakistan, and Nigeria. Following the widespread use of poliovirus vaccine in the mid-1950s, the incidence of poliomyelitis declined dramatically in many industrialized countries. A global effort to eradicate polio began in 1988, led by the World Health Organization, UNICEF, and The Rotary Foundation. These efforts have reduced the number of annual diagnosed cases by 99%; from an estimated 350,000 cases in 1988 to a low of 483 cases in 2001, after which it has remained at a level of about 1,000 cases per year (1,606 in 2009). Polio is one of only two diseases currently the subject of a global eradication program, the other being Guinea worm disease. So far, the only diseases completely eradicated by humankind are smallpox, which happened in 1979, and rinderpest in 2010. A number of eradication milestones have already been reached, and several regions of the world have been certified polio-free. The Americas were declared polio-free in 1994. In 2000 polio was officially eliminated in 36 Western Pacific countries, including China and Australia. Europe was declared polio-free in 2002. As of 2012, polio remains endemic in only three countries: Nigeria, Pakistan, and Afghanistan, although it continues to cause epidemics in other nearby countries due to hidden or reestablished transmission. For example, despite eradication ten years prior, an outbreak was confirmed in China in September 2011 involving a strain prevalent in neighboring Pakistan. Since January 2011, there were no reported cases of the disease in India, and hence in February 2012, the country was taken off the WHO list of polio endemic countries. It is reported that if there are no cases of polio in the country for two more years, it will be declared as a polio-free country.
Christopher Hitchens wrote that he learned in 2005 that in Northern Nigeria—a country which at that time was considered provisionally polio free—an Islamic Fatwah was issued declaring that the polio vaccine was a conspiracy by the United States and the United Nations against the Muslim faith, saying that the drops were designed to sterilize the true believers. Subsequently, polio reappeared in Nigeria and spread from there to several other countries.
Read more about this topic: Poliomyelitis