Well how the evidence is presented is a little misleading!

The plots often presented to support this theory are often plotted as deaths not cases. There are several reasons that deaths were declining from these diseases, principally better hygeine and better treatment of secondary infections that often killed the victims in years past lead to better survival of these viral diseases. If you look at the number of reported cases fo these diseases the rate if infection does not begin to decline until immunization programs began. The real question should address the number of infected patients not just those who died if you are going to gauge the effectiveness of immunization programs. Tweet