The Children's Hospital of Philadelphia
Vaccines: Separating Fact From Fear - Why are There So Many Vaccines?

Parent: Why are there so many vaccines nowadays?

Paul A. Offit, MD: I think that the answer to that question lies in our past. My mother and father were children in the 1920s and the early 1930s, and at that time there was just one vaccine, the small pox vaccine. But they were lucky. They were lucky that they weren't one of the hundreds of thousands that got diphtheria, many of whom died. By the time my brother and my sister and I were children, which was in the 1950s and early 1960s, there were five vaccines. But we too were lucky. We are lucky that we weren't one of the tens of thousands that got bloodstream infections or meningitis or pneumonia from bacteria like haemophilus or pneumococcus. Now, our children get 11 vaccines. And while we still live in a world where there are viruses and bacteria in our midst that can cause permanent harm or death, we still do need vaccines to protect us.