The number of reported wild polio virus cases decreased by 52% worldwide, from 1,352 cases in 2010 to 650 cases in 2011, according to the Centers for Disease Control and Prevention.
This progress occurred despite a shortage of funding to eradicate polio globally, a goal that the World Health Organization established in January of this year.
The achievement of polio eradication also varied significantly by region.
In India in 2011, the number of cases declined 98%, and the last identified case was in January of that year. The country is now considered polio-free.
Cases increased, however, in Afghanistan (by 69%), Nigeria (by 66%), and Pakistan (by 27%) in 2011, and circulation there continues, according to the May 18 Morbidity and Mortality Weekly Report (MMWR 2012; 61[19]:353-7).
Outbreaks continue to occur as a result of importation from polio-reservoir countries to areas previously polio free for 12 or more months; 11 different outbreaks occurred globally, including 9 new outbreaks in eight countries, including China and seven countries in Africa, according to the report.
In the first quarter of 2012, 59% fewer cases have been reported worldwide, compared with the same period in 2011, and all wild polio virus cases were reported from Afghanistan, Chad, Nigeria, and Pakistan. No new outbreaks have been reported, but persistent circulations, particularly in Nigeria and Pakistan, pose an ongoing threat to eradication efforts.
Following the WHO’s 2012 declaration regarding the public health emergency posed by ongoing poliovirus transmission, countries with endemic or reestablished transmission developed national emergency plans for interrupting transmission.
If global eradication is to be achieved, full implementation of these emergency plans is urgently needed, according to an editorial note included in the report.