In light of this year's large measles outbreak I'm getting this question frequently from adults. Mostly these questions come from people over the age of 40 who are not 100% sure of their vaccine status and didn't have measles as children. The simple answer to this question is "NO," but there are some variations on this answer. The vast majority of adults in the U.S. are immune to measles. Once vaccinated (or if you had the measles - which includes almost everyone born before