When I was a child measles, mumps, rubella, chickenpox, pertussis, bacterial pneumonia, polio, etc. were all common. Smallpox still existed and was killing people. Now smallpox is extinct, and polio is on verge of becoming extinct. The other diseases are rare in the US and other developed countries. But if the vaccination rate for measles falls below 90% there will be outbreaks - and measles is a nasty virus with >142,000 dying from this disease world-wide in 2018. It can also cause blindness and the loss of hearing. Influenza kills 12,000 - 50,000/yr in the US. Then we have Covid causing >920,000 dead in the US in 2 yr.
The public health community needs to mount a campaign to remind people just how effective vaccines are and that they are well tested before being approved. The rates of significant side effects are trivial.
One other vaccine that has had a profound effect - rabies vaccine. It is primarily a veterinary vaccine and the effect is that almost no one dies from rabies. It should be remembered that rabies is a 100% fatal disease if not treated by vaccination.
My point is that vaccines are lifesavers and have changed the world in which we live. All they do is to train our immune system to recognize and inactivate &/or kill invading pathogens (bacteria, viruses, protists). They are amazing and reading about vaccines and the insights that the various scientists had in developing them is one of the things that attracted me to becoming a microbiologist.
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