The Bottom Line Vaccinations are safe. A very small share of people have allergic reactions, which are treatable. There are some extremely rare adverse events, most of which occur in immune-compromised children. The only more common risks are fever and febrile seizures, which are also rare and do not do long-term harm. There is no evidence of a link between vaccines and autism, and much evidence to refute such a link. Vaccines prevent children from getting sick.
