You may be in the crosshairs of the measles crisis and not even know it.

Public officials are urging people to double check their immunization records, even if they believe they’ve been vaccinated for the measles, usatoday.com reports.

Those who have received two doses of the measles, mumps, rubella vaccine (MMR), should still ask to have the antibodies in their blood checked, especially if they’ve been to one of the growing number of exposure sites, the report says.

That goes for those who had measles as a child or were born prior to 1957 and are considered immune by the US Centers for Disease Control and Prevention, the report says.

But even folks born between 1957 and 1989, when authorities were administering just one dose of the MMR vaccine instead of two, might not be safe. The CDC began recommending two doses of the vaccine in 1989.