Did you go to the Orioles-Blue Jays baseball game at Camden Yards last Friday? Did you stop at Applebee’s in Easton the night before? If so, you may have been exposed to measles, the Maryland Department of Health and Mental Hygiene says.

An individual from New York City who was in the greater Baltimore area during his entire infectious period is believed to have carried the virus. Maryland, a state with a high rate of immunization and which is trying to safeguard its record of more than 18 months without a measles case, wants people to be aware of the signs of infection, which would occur between June 7 and June 24.

The exposure may have occurred at at least five different places.

l Tuesday, May 31 at the Catonsville Giant grocery store, 6223 Baltimore National Pike, between 5 and 8 p.m., and Montgomery Plaza Liquors, 6225 Baltimore National Pike, Catonsville, between 6 and 8 p.m.

l Wednesday, June 1: Catonsville High School Graduation, UMBC RAC Center, between 6 and 11 p.m.

l Thursday, June 2: Applebee’s Restaurant, 8999 Ocean Gateway Dr., Easton, between 6:30 and 11 p.m.

l Friday, June 3: Oriole Park at Camden Yards, beginning at 7 p.m., and MTA Light Rail from 11 p.m. until 1:30 a.m. Saturday, June 4.

In the first stage, most people have a fever over 101 degrees, runny nose, watery red eyes and a cough. In the second stage, which begins around the third to seventh day, a rash appears on the face and spreads over the entire body.

“People who may have been exposed should be vigilant for the signs and symptoms of measles,” said Frances Phillips, deputy secretary for Public Health Services, in a statement. “Quick identification and medical attention for new cases can help reduce the spread.”