Did your child have a fever after getting their MMR vaccine?
Is that a normal reaction?
Why Did My Child Get a Fever After Their MMR Vaccine?
It is no secret that a fever is a common side effect after getting a vaccine.
In most cases, that fever starts within 12 to 24 hours of getting a vaccine and only lasts for a few days.
With the MMR vaccine (MMR-II or Priorix), the fever might be delayed by up to 7 to 12 days though!
Why?
A fever is a common nonspecific immune response.
"Vaccines prepare the immune system to protect against viruses or bacteria that could make people sick. The way this happens is that they introduce components of the germs that are known to activate the immune response. However, vaccines will not cause a significant enough immune response that the person suffers untoward events, such as can occur during natural infections. With this said, in some cases the immune response is strong enough to cause detectable symptoms, like a mild fever."
Fever and Vaccines
So getting a fever after a vaccine simply means that your immune system is working!
And no, it doesn't mean your immune system isn't working if you don't get a fever.
And it certainly doesn't mean that your child has developed measles if they have developed fever after their MMR vaccine, even if they also develop a rash.
A rash which might also be delayed.
What to Do if Your Child Develops a Fever After Their MMR Vaccine
If your child has developed more than a low grade fever that is bothering them after their MMR vaccine, you should likely give them an age-appropriate dose of a non-aspirin fever reducer. And of course, you should call your provider or have your child seen if the fever isn't going away in a few days, if your child isn't consolable, isn't eating or drinking at all, is hard to wake up, or is having trouble breathing, etc.
Could this fever trigger a febrile seizure?
Yes, it can.
Febrile seizures are not rare after the first dose of MMR vaccine. They are more common if your child received the combined MMR and chicken pox vaccine in one injection.
Fortunately, these febrile seizures are not considered to be serious.
And it is important to understand that neither a fever or a febrile seizure after a vaccine, including the MMR, is a vaccine injury. They do not cause long term issues for your child.
On the other hand, if your child skipped the vaccine and developed measles, in addition to developing a high fever and having an even higher risk of febrile seizures, they would be at risk for more serious complications and even death.
More on Vaccine Reactions
- Everything You Need to Know About the Measles Vaccine
- Why Are You Still Worried About the MMR Vaccine?
- How Often Do Severe Events Occur After Vaccines?
- How Long Do Side Effects of Immunizations Last?
- Is This a Horrible Vaccine Reaction?
- Symptoms of Vaccine Reactions
- Fever and Vaccines
- CDC - MMR (Measles, Mumps, and Rubella) VIS
- CDC - Before, During, and After Shots
- CDC - MMR & Varicella Vaccines or MMRV Vaccine: Discussing Options with Parents
- I Felt Sick After Getting a Vaccine. Why?
- Vaccine Side Effects and Adverse Events
- What to do if your child has fever after a vaccine
- What to expect after vaccinations
- What is normal after vaccination?
- Immunization after care for children
- Assessing the risks of vaccine side effects
- Posts Mislead About Measles, MMR Vaccine Amid Recent Outbreaks
- Rand Paul Repeats Baseless Vaccine Claims
- Measles: the plague that ruined Rome
- Malicious Measles Myths
- Measles complications – why the MMR vaccine is so important to children