AUGUSTA (AP) – Maine health officials say they’ve identified a cluster of four cases of whooping cough in southern Maine.

According to the Maine Center for Disease Control and Prevention, the cases were reported in girls ages 8 to 10 living in the Biddeford-Saco area. The sick children attend three different schools, but have common exposures at an after-school program and an athletic facility.

Health officials say a number of other people are undergoing testing after showing whooping cough symptoms.

Whooping cough, or pertussis, is a highly contagious respiratory infection caused by bacteria that can result in a persistent, severe cough.