The Bartow County jail quarantined all inmates after some tested positive for COVID-19, the sheriff’s office announced Wednesday.

The agency’s statement didn’t say how many inmates had tested positive, but Northwest Georgia Public Health District spokesman Logan Boss said there are around 30 confirmed cases.

“We expect more,” Boss said, citing the virus’ proclivity for quick spread in jails and prisons where people are held close to one another. The online jail roster says 683 inmates are housed at the facility in Cartersville, about 45 miles north of Atlanta.

The outbreak is the latest in a long string to hit jails and prisons across the state since March, including at Pulaski State Women’s Prison, Lee State Prison, the Clayton County jail and many others.

Bartow Sheriff Clark Milsap said the inmates who tested positive largely aren’t showing symptoms. He hoped the quarantine would stem the spread, but the news release didn’t explain exactly how the quarantine would work. He said he and his staff are following state health department guidelines and recommendations.

Boss said the health department is advising the jail to follow Centers for Disease Control and Prevention guidelines on quarantining incarcerated people. The guidelines include repeated testing and close monitoring for symptoms.

Boss said no one from the jail has been hospitalized.

The sheriff’s news release dismissed what he called “mistruths” on social media about how the jail is handling COVID-19. Milsap didn’t say what he was talking about, but Facebook users have in recent days accused staff of refusing to test inmates who ask for screening.

“Some folks just like to spread rumors and panic when there is no need,” Milsap said. “I can assure you that we are monitoring all the inmates in the facility.”

The jail, which had a $30 million expansion in 2011, is built to hold more than 1,000 people.