One staff member, a corrections officer, has tested positive for COVID-19 at Jefferson Correctional Center - the first case at the prison - the state's Department of Corrections confirmed Tuesday.
DOC spokeswoman Karen Pojmann said Tuesday the staff member was tested last week, and has not been at work since.
Pojmann said contact tracing and testing had not found any other COVID-19 cases among offenders or staff at JCCC.
The department's protocol after a positive test for the disease in a staff member includes that the employee remains at home on leave until they test negative.
All staff who were in close contact with someone who tests positive are also sent home to quarantine for two weeks.
There's also currently one active staff case at Algoa Correctional Center in Jefferson City, according to DOC's COVID-19 data website.
One staff member at Algoa had also recovered, as had ACC's one reported offender case.
Pojmann said, "Offenders who test positive for COVID-19 are isolated until they test negative."
At JCCC, she said, "We completed mass testing of all staff and offenders there, and continue to perform sample testing and other forms of testing."
Pojmann also outlined testing that continues at all DOC facilities:
Testing of offenders who exhibit symptoms of COVID-19 or who may have been in contact with an infected person started in March.
Testing of offenders upon first entering the prison system - and one week before leaving the system - began June 1.
Testing of all offenders and staff in a housing unit or other contained area is conducted any time an outbreak is suspected.
Between May 26-Aug. 13, DOC also tested all offenders and staff at all facilities.
"This type of testing has revealed asymptomatic positives, as reflected in the data," Pojmann said.
"Sample testing, or surveillance testing of a random 10 percent of the population of each facility, began Aug. 10 and will continue at facilities throughout the state," she added.
Elsewhere in Mid-Missouri, according to DOC's online data, since March, there have been a total of eight cases among staff and a total of 25 cases among offenders at Fulton Reception and Diagnostic Center.
Two of the staff cases at FRDC and 13 of the offender cases are active.
At Cremer Therapeutic Community Center in Fulton, one offender has recovered.
At Tipton Correctional Center, one offender case was listed as active out of a total of four; the other three had recovered.
Throughout its system, DOC reported 259 active inmate cases and 110 active prison staff cases - not yet including the JCCC staff member's case.