Risk of febrile convulsions after MMRV vaccination in comparison to MMR or MMR+V vaccination.

Abstract Background In July 2006, Priorix-Tetra™, a combined measles-mumps-rubella-varicella (MMRV) vaccine, was licensed in Germany. Since a postlicensure study had shown a more than twofold elevated risk of febrile convulsions (FC) after first dose vaccination with the combined MMRV vaccine ProQuad ® compared to separately administered MMR and V vaccines (MMR+V), the Paul-Ehrlich-Institute, the German regulatory agency for vaccine licensing and safety, requested a study investigating the risk of FC for Priorix-Tetra™. Methods We performed a matched cohort study based on claims data of more than 17 million insurees in the German Pharmacoepidemiological Research Database. All children born …