Abstract

Vaccination is one of history's most successful public health interventions. Since 2000, vaccination campaigns against measles, which is highly contagious but preventable through the measles‐mumps‐rubella (MMR) vaccine, have reduced both the global incidence of the disease and measles deaths by 80 percent. However, progress toward measles elimination has slid backward in several previously well‐protected global regions. With more communities below or at risk of falling below the 95 percent immunization rates required for herd immunity—due more and more to vaccine skepticism and declination rather than lack of access—many U.S. states and countries must reappraise their vaccination policies and programs.