The vaccination effect: 100 million cases of contagious disease prevented

Vaccination programs for children have prevented more than 100 million cases of serious contagious disease in the United States since 1924, according to a new study published in The New England Journal of Medicine. The research, led by scientists at the University of Pittsburgh’s graduate school of public health, analyzed public health reports going back to the 19th century. The reports covered 56 diseases, but the article in the journal focused on seven: polio, measles, rubella, mumps, hepatitis A, diphtheria and pertussis, or whooping cough. Researchers analyzed disease reports before and after the times when vaccines became commercially available. Put simply, the estimates for prevented cases came from the falloff in disease reports after vaccines were licensed and widely available. The researchers projected the number of cases that would have occurred had the pre-vaccination patterns continued as the nation’s population increased. The journal article is one example of the kind of analysis that...