Amid a serious measles resurgence in the United States, the Center for Disease Control has issued a calling to people vaccinated between 1963 and 1967:  You may need additional shots.

It turns out that there were two measles vaccinations issued between 1963 and 1967, and one of them didn’t work.

Why those specific years? It turns out that there were two measles vaccinations issued during that period, and one of them didn’t work.

This version was discontinued in 1967, when it was found to be ineffectual, and replaced in 1968 by a new version that remains in use today, according to an article in Forbes.  

The CDC recommends that any adult lacking evidence of immunity get at least one dose of the MMR (Measles, Mumps, Rubella) vaccine; and if tracking down your immunization records from 50 years ago is too daunting a task, then consult with a medical professional about having your blood checked for immunity.

Meanwhile, measles cases keep ramping up. According to the CDC, 2019 has seen the greatest number of confirmed measles cases since 1994, and there have been reported cases in 22 states.

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