TIME: Historic Global Vaccine Rollout Could End Polio Forever
Walter Orenstein, associate director of the Emory Vaccine Center, professor at Emory University, and former director of the United States’ National Immunization Program

“…Since we no longer need to protect against wild type 2 [polio virus], we’re replacing the trivalent vaccine with a bivalent version that doesn’t include the type 2 strain and thus significantly reduces the risk of vaccine-derived polio. This is a massive effort as the current vaccine must be removed from all health facilities in 155 countries and replaced by the bivalent vaccine — all over a two-week period. This switch is one of the final steps in the polio endgame plan to stop the disease once and for all. … This globally coordinated vaccine project will yield important lessons for strengthening immunization more broadly. … As we embark on this global switch, we will learn more about how to deliver vaccines all over the world and protect children from other diseases that kill millions each year…” (4/27).