If you were vaccinated for measles in the 1970s and 80s you may not be protected: Doctors

TAMPA, Fla. - If you thought you were vaccinated for measles, you may want to double-check.

Doctors say the shot some people got who were born in the 70s and the 80s actually wore off after about 20 years, putting them at risk of contracting the virus.

Unless you work in the healthcare field or attended college in the 90s where it was required, you may not know that it wore off. It's not clear how many people may fall in the category, but USF College of Public Health Associate Professor Jill Roberts is one of them and says if you are in the category and want to be protected now, you should get re-vaccinated, especially with the outbreak continuing to spread.

As measles cases reach the double digits in Florida, doctors are reminding adults who were vaccinated as kids to make sure their shot is still effective.

READ: Florida's 9th case of measles confirmed in Polk County: Health officials

"There are people who are vaccinated with the previous version who may actually have the immunity waning," Dr. Roberts said.

That's because some babies born in the 1970s and 1980s received a single shot that was made differently and only protected against measles. As opposed to the current MMR vaccine which USF Professor Dr. Jill Roberts says started being widely available in the 1980s and protects against measles, mumps and rubella.

"What we found is there's this age group that actually was between the two vaccines and sometimes those people either were missing one dose or they got a dose of one and then the dose of the other, and they're just not covered quite with the highest amount of immunity," Dr. Roberts said.

Dr. Roberts was actually one of them but didn't learn about it until years later, when she enrolled in college.

"We started seeing some measles outbreaks, so universities were one of the first to say, all right, if we have people coming in, and they're around this particular age, they've got to have another MMR vaccine before we'll actually let them in," Dr. Roberts said.

READ: British mom who lost 6-year-old son urges vaccinations as measles outbreak spreads to Tampa Bay Area

As Roberts explains, if you weren't at a college that required it or don't work in the medical field with patients you may have never been informed. That's why she says if you think you may be in that group and want to be protected, take action now.

"Check in with your health care provider and see whether they have records. We always know records come, records go. We change providers. There's absolutely no risk in getting another MMR so if you don't know, just go get another shot. They're inexpensive and widely available," Roberts shared.

Roberts says this mainly affects people who are now in their 40s and 50s. Like we've mentioned, measles is extremely contagious. If you're unvaccinated and exposed to the virus, you have about a 90 percent chance of getting the virus.

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