In addition to taking precautions against the novel coronavirus, schools across the country find themselves needing to worry about a new scourge: legionella bacteria in their drinking water, according to The New York Times.

Recently, nine schools in Ohio and Pennsylvania found the harmful bacteria in their water. In Fox Chapel, PA, a suburb of Pittsburgh, four out of the town’s six schools tested positive for the bacteria. Because the schools were unused for so long, nearly six months, the water just sat in the pipes and did not have a chance to move. That created a condition for the bacteria to thrive, according to WPXI News in Pittsburgh.

According to the Centers for Disease Control and Prevention, people get sick when they inhale mist that has the bacteria or they ingest water with the bacteria in it. It can cause severe pneumonia or lung infection, which is worrying when the nation is already grappling with COVID-19, an infectious disease that leads to severe pneumonia.

Lets watch out for our kids when they go back to school!