Combined MMR vaccine tied to febrile seizures

A higher risk of brief, fever-related seizures has been tied to a combination vaccine for measles, mumps, rubella and chickenpox as compared to giving two separate shots.

The combination vaccine may cause febrile seizures, pediatricians said, reports, which are fever-related convulsions that last less than one minute and do not lead to epilepsy, seizure disorders or lasting damage.

The results were revealed following a study comparing seizure and fever reactions among 83,107 children between the ages of 12 and 23 months who received the combined vaccinations with 376,354 toddlers who received separate shots.

The four-in-one combination vaccine was found to have caused one extra seizure for every 2,300 doses, Dr. Nicola Klein, co-director of the Kaiser Permanente Vaccine Study Center in northern California, and her colleagues reported in Monday's issue of the journal Pediatrics, reports.

Klein added that concerned parents should understand that the risk for a seizure is low.

Dr. Randy Bergen, a pediatrician and infectious disease specialist at Kaiser Permanente-Walnut Creek in California, told that it is more common for a child to suffer a febrile seizure from a simple cold than by an immunization.

Additionally, the seizure risk is only during a three day window, seven to 10 days after vaccination.