Comparing vaccines to DDT seems backwards to me.

Perhaps we're more afraid of DDT than we should be, but DDT is moderately toxic and has a soil half-life of up to 15 years. (Compare this to a few weeks for Malathion or a few months for Glyphosate.) Bed bugs suck, but they never killed anybody.

Compare this to measles or whooping cough where the vaccine is very safe and the diseases can permanently scar or kill victims.