New York Times: For Polio Vaccines, a Worldwide Switch to New Version
“Starting on Sunday, more than 150 countries and territories will switch to a new oral polio vaccine. It will be the first worldwide vaccine change ever attempted. Polio is on the edge of eradication. There were only 74 cases last year, all in Pakistan and Afghanistan. This year, there have been only nine, also in those two countries…” (McNeil, 4/11).