Silver Book Fact
Drastic reduction of morbidity from vaccine-preventable disease in 20th century
In the 20th century, vaccines have reduced the morbidity from vaccine-preventable diseases by as much as 89–100%.
Pharmaceutical Research and Manufacturers of America. Vaccine Fact Book 2013. Washington, D.C.: PhRMA; 2013. http://www.phrma.org/sites/default/files/pdf/PhRMA_Vaccine_FactBook_2013.pdf