The US Centers for Disease control and Prevention has changed its thinking on how toddlers should be vaccinated against chickenpox, otherwise known as varicella.
A CDC committee recently recommended the combination measles, mumps rubella and varicella vaccine, or MMRV, over separate shots of MMR and chickenpox vaccines.
But new data is showing a higher risk of fever and seizures in the week or so after MMRV vaccinations in 1-to-2-year-olds. As a result, the CDC's advisory committee is no longer recommending the MMRV combination shot over two separate injections.
The study appears in Morbidity and Mortality Weekly Report.