In April 2016, a resolution by all members of the 68th World Health Assembly* in coordination with the Global Polio Eradication Initiative (GPEI) resulted in the removal of the Sabin-strain type 2 oral poliovirus vaccine (OPV) component from all immunization activities to avert outbreaks of type 2 circulating vaccine-derived poliovirus (cVDPV2). In the first quarter of 2016, house-to-house supplementary immunization activities (SIAs) with trivalent OPV (containing Sabin-strain types 1, 2 and 3) were conducted in 42 at-risk countries† in an effort to close type 2 immunity gaps in countries with chronically weak routine childhood immunization systems.