One 2008 study indicated a rate of febrile seizures of 9 per 10,000 vaccinations with MMRV, as opposed to 4 per 10,000 for separate MMR and varicella shots; U.S. health officials known as the ACIP therefore do not express a preference for use of MMRV vaccine over separate injections.
A study in 2008 indicated that febrile seizures were more common with MMRV vaccinations (9 per 10,000) compared to separate MMR and varicella shots (4 per 10,000); U.S. health officials known as the ACIP do not favor one vaccine over the other.