The Center for Disease Control says many adults may need to get a booster shot for highly contagious diseases, such as measles.
As of Monday, the number of measles cases this year is now at 626, the second-highest in more than a decade, according to the Centers for Disease Control and Prevention.
Nearly two decades ago, the measles was declared eliminated in the United States, but there has been a recent upsurge of cases, including adults who thought they were already protected.
Depending on when you were born, you might not have been given the vaccine at all.
If you were born before the ‘60s, you might have never been vaccinated, because it was assumed you would be exposed to the virus and would build immunity.
The group of adults that may be at risk are Generation X, born in the late ‘60s, ‘70s and ‘80s.
These adults may have been vaccinated, but never built immunity, mostly because of the way the vaccines were administered.
There was a change in 1989, when the Center for Disease Control began recommending two doses of the MMR vaccine, which covers the measles, mumps and rubella, making the vaccine consistently more effective.
The Center for Disease Control says two doses of the MMR vaccine are about 97-percent effective at preventing measles. One dose is about 93-percent effective.
If you are unsure of your immunity, contact your doctor. The Center for Disease Control says it is safe to get another dose.