Must a baby get fever as a sign that the vaccination is working?
With the vaccines approved today, vaccination reactions have become significantly less frequent. Only about one to ten percent of vaccinated children develop fever after a vaccination.This does not mean that the vaccination has not worked, but that the body gets to know the pathogen without a strong reaction. The myth of the necessary vaccination reaction comes from the smallpox vaccination, in which children used to have to develop a smallpox scar in order for the vaccination to work safely.