CDC scientists admit that 90% of infectious disease mortality decrease in the United States happened before vaccines were available.
Annual Summary of Vital Statistics: Trends in the Health of Americans During the 20th Century
Bernard Guyer, MD, Mary Anne Freeman, MA, Donna M. Strobino, PhD, Edward J. Sondik, PhD. Pediatrics, Dec 2000, Vol. 106, No. 6.
“Thus vaccination does not account for the impressive declines in mortality seen in the first half of the century…nearly 90% of the decline in infectious disease mortality among US children occurred before 1940, when few antibiotics or vaccines were available.”