CHICAGO — A COVID-19 drive-thru testing site on the Northwest Side is giving priority to medical personnel and first responders, but many are running into long lines and leaving untested.

Demand has outweighed supply all week at the Forest Preserve testing site, located at 6959 Forest Preserve Dr. in Dunning, where a long line of cars has been a constant.

Hundreds of first responders and medical professionals are eager to know whether they are carrying coronavirus and possibly endangering others.

For now, the state-run site is for those frontline workers only. But due to limited test kits, only 250 can be tested per day.

So Thursday morning, first responders and healthcare workers got in a line that stretched for blocks before drive-thru testing started at 9 a.m.

Many on the frontline want to know their status for fear they’re infecting the people they serve.

There were 11 positive tests on the first day alone.

The National Guard is assisting in the operation, which is near Harlem and Irving Plaza. The Guard is also assisting in the distribution of personal protective equipment.

To facilitate more large shipments in the days ahead, the United Center is being transformed into a logistics hub. With suspended seasons for both the Bulls and Blackhawks, the UC will be used for food distribution, first responder staging and collection of critically-needed medical supplies.

The testing is scheduled to end at 5 p.m. Thursday, but it has shutdown early all week, with the 250 available kits running out by the early afternoon.