Eliminating measles in the U.S. and the lost \u2018memory\u2019 of disease<\/p>\n
Measles vaccines first became available<\/a> in the U.S. in 1963. Since then, the vaccine has been modified, improved and combined with vaccines for the mumps and rubella viruses to form today\u2019s MMR vaccine.\n<\/p>\n By 2020<\/a>, U.S. cases of measles dropped dramatically, and the few cases reported nationally each year were mostly related to international travel and isolated incidents.\n<\/p>\n \u201cThis was the most, is the most, contagious infectious disease of humans, and we eliminated it. Amazing,\u201d Offit said during a recent panel hosted by the Association of Health Care Journalists.\n<\/p>\n But the elimination of the disease had unintended consequences, Offit said.\n <\/p>\n \u201cWe largely eliminated the memory of measles,\u201d he said. \u201cI think people don\u2019t remember how sick or dead that virus can make you.\u201d\n<\/p>\n Because of that, some adults who grew up in recent decades never got vaccinated, he said.\n<\/p>\n \u201cWhat you\u2019re seeing now are people in their 20s, 30s and 40s who grew up at a time when this virus wasn\u2019t circulating,\u201d Offit said. \u201cSo, they\u2019re not naturally infected. They\u2019ve also, for whatever reason, not been vaccinated. So, you now have a fairly large population of susceptible adults.\u201d\n<\/p>\n Immunization rates among school-aged children in Pennsylvania and across the U.S. have also steadily declined in recent years<\/a>, national data shows.\n<\/p>\n