Executive Summary

The emergency An unprecedented intensity of polio eradication activities in 2010-11 resulted in several landmark successes. India became polio-free and global cases decreased by 52%; of the four countries with re-established poliovirus transmission, South Sudan and Angola have not recorded a case since June 2009 and July 2011, respectively, while cases fell substantially in the second half of 2011 in Chad and the Democratic Republic of the Congo. All importation-associated outbreaks in eight previously polio-free countries in 2011 were stopped, all but one (in Mali) within six months.

In the three remaining polio-endemic countries, however, polio cases soared from 2010 to 2011 (in Afghanistan by 220%, in Nigeria by 185% and in Pakistan by 37%), with the most dramatic rise in the second half of 2011. Polio also spread internationally from Nigeria and Pakistan, underscoring the risk that endemic poliovirus transmission continues to pose globally.

In addition, recent polio outbreaks on three continents highlighted the unacceptable consequences of failure. In China, Tajikistan and Congo, explosive outbreaks following importations affected both adults and children, due to the changing susceptibility patterns; in some areas, the adult case fatality rates approached 50%.

Polio eradication is at a tipping point (Figure 1). If immunity is not raised in the three remaining countries to levels necessary to stop poliovirus transmission, polio eradication will fail. All three countries still face a variety of barriers to reaching each child with the oral polio vaccine (OPV) including weak public infrastructure and health systems, insecurity, largescale population movements, corruption, political change, and insufficient accountability.