Deering High School in Portland.

Portland Public Schools are warning parents about several cases of whooping cough.

School officials confirmed three cases of pertussis in the district.

They say there have been confirmed cases in Longfellow Elementary School, Lincoln Middle School and Deering High School.

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They’ve also told parents about another suspected case at Longfellow.

The district says school nurses will continue to monitor the situation, work with the Maine Center for Disease Control and Prevention and keep families posted.

The CDC suggested ways to prevent pertussis:

— Cover your mouth when you cough or sneeze

— Throw used tissues away in a waste basket.

— Cough or sneeze into your upper sleeve or elbow

— Wash your hands often with soap and water for at least 20 seconds

There were 33 pertussis cases reported statewide in March compared to 25 cases during the same period in 2018.

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