Being vaccinated is a duty simply for all those that can't...
Some people are allergic to vaccins and if you're not vaccinated you allow the disease to spread to them.
Someone vaccinated can't get REALLY harmed even if they can get slithly sick. But very young children and people enable to take vaccins are still affected.
Pretty much everyone is 'allergic to vaccines'. Scientifically speaking, that's kind of the point.
The propaganda you've been fed here falls apart because vaccines are injected into most everyone without any sort of testing to see if they might produce a negative reaction in that individual.
The 'test' seems to be the way witches were detected back in the day; throw a woman into a lake. If she swims, she's a witch. If she drowns, she wasn't a witch.
Allergy to the vaccine is not the only cause of complications after vaccination. It often happens that the child after the disease has weakened the immune system, but parents lead him to the vaccine. It is the responsibility of parents, but not the issue of vaccination.