Researchers in Australia have found more evidence that children do not have an increased risk of seizures if they receive the combined MMRV vaccine for their 2nd dose of the MMR immunization series.
The study was published by Dr. Kristine Macartney in JAMA Pediatrics and the conclusions based on data from children in Australia.
The researchers found that giving the MMRV vaccine for the 2nd shot in the immunization schedule did not increase the child’s risk of having a seizure. Other studies show that MMRV increases their risk of seizure when it is given as the 1st shot.
MMRV is a vaccine that combines immunizations against measles, mumps, rubella, and varicella (chickenpox) into one vaccine. In comparison, MMR vaccines do not include the varicella component.
MMR vaccines are typically given in a series 2 shots, with the 1st shot given at the age of 12 months and the 2nd shot given between the ages of 4-6 years old. Some children may require a 3rd shot of MMR.
MMRV is not recommended for the 1st does in the MMR series because studies show that it doubles a child’s risk of developing a high fever that causes a seizure (called a “febrile seizure”).
The risk of having a seizure is approximately 1 in 1,250 for children who get the MMRV vaccine for their 1st shot in the series, vs. approximately 1 in 2,500 for children who get the MMR vaccine, according to the Centers for Disease Control and Prevention (CDC).
“CDC recommends providers who choose to use the combination MMRV vaccine be aware of and clearly communicate to parents and caregivers the increased risk of fever and seizure within the 7 to 10 days following vaccination.”
For more information:
- MMRV and Febrile Seizures – CDC
- Childhood Vaccines and Febrile Seizure Concerns
- Febrile Seizures Following Childhood Vaccinations, Including Influenza Vaccination