BALTIMORE — The harsh flu season has put “a significant” stress on Maryland’s hospitals and emergency services.

State health officials said in a press release Thursday that hospitals are being overcrowded. They’re urging only the very sick to visit an emergency room.

There’s a normal increase in the number of people who go to the hospital in the winter for flu and respiratory illnesses. But the Maryland Department of Health has reported widespread cases.

Public Health Services Deputy Secretary Dr. Howard Haft said, “please be sure there is a true emergency before calling 911.”

Officials said doctors and urgent care centers can treat milder symptoms.