[burfog]

That in turn causes other trouble.

People adjust for perceived risk. For example, seatbelts and airbags make people less careful when driving.

Vaccination makes people less careful about disease. There is no vaccine for enterovirus-68, which sometimes paralyses people. There is no vaccine for adenovirus-36, which is a cause of obesity. I could go on for a long time I think; lots of "harmless" viruses are turning out to cause serious problems. They can damage your heart, set off dementia, or give you cancer.

The only effective answer is avoidance. This requires learning and behavior modification, so it isn't too popular, but nothing else is as effective.

[wanderfowl]

I'm having a [Poe's law](https://en.wikipedia.org/wiki/Poe%27s_law) moment here. You've just applied Abstinence Only Sex Education 'logic' to infectious disease. This is either brilliant satire of the odd arguments against harm reduction in general, or... you're serious, and I agree, it's a crying shame nobody taught all those poor smallpox victims how to modify their behavior.