My perception was that most infants all over the world now receive shots like MMR, TDaP and IPV. The herd immunity gained through this exercise automatically ma

My perception was that most infants all over the world now receive shots like MMR, TDaP and IPV. The herd immunity gained through this exercise automatically makes us less susceptible to certain diseases which were widespread even 50-60 years ago, and in turn, more healthy, even at old age.