The vast majority of all children will have no adverse reaction whatsoever to a vaccine. A small percentage may have a mild reaction, and only a tiny fraction of those will actually have a noticeable and dangerous reaction to their vaccination.
Of the mild reactions to vaccinations, a slight rash, swelling at the site of the injection, and a low grade fever that lasts a couple of days are the most common.
The MMR vaccine may cause a fever and a rash seven to ten days after it is administered, and the DTaP vaccine can cause one baby in one thousand to cry inconsolably for a few hours.
Sometimes, a more severe fever results from a vaccination. Although this can lead to a seizure, it is non fatal, and there will be no lasting damage. If your child shows signs of severe allergy or anaphylaxis, then you need to seek immediate medical attention. These symptoms include wheezing or shortness of breath, hives, rapid heartbeat or paleness, as well as fainting or dizziness. The reaction is usually seen shortly after the vaccine is administered – anything from a few minutes to a few hours. This is a potentially fatal reaction, and immediate, emergency medical care should be your first course of action.
