[Fomite]

Talking about side effects that are of public health concern.

The smallpox vaccine could blind you if you touched the vaccine site and then your eye. It had a 1 or 2 deaths per million vaccines side effect rate.

The live-attenuated polio vaccine can revert to wild type.

"Moderna has a high rate of fever and soreness at the injection site" because it's doing it's job is a very different thing.