Local health officials are reporting a COVID-19 outbreak among people who attended a church retreat in Ohio several weeks ago.

Dayton and Montgomery County public health officials said more than 800 people attended the Baptist Church retreat at Camp Chautauqua in Miamisburg from June 27 to July 3. The retreat included attendees and churches from Ohio, Kentucky, Illinois and Indiana.

Officials said at least 30 cases among attendees living in Ohio and Kentucky have been identified so far.

Health officials said camp and event organizers haven’t provided contact information for attendees, so authorities are asking anyone who may have attended to contact them or their local health department.

The outbreak demonstrates that the COVID-19 virus is still circulating and continues to make people sick, said Dr. Michael Dohn, medical director for Dayton & Montgomery County Public Health.