The ministry said it was working with the Toronto Public Health Unit “to mitigate the impact on staff and inmates.”
“In accordance with public health advice, all close contacts of staff and inmates are self-isolating and / or tested as appropriate,” ministry spokesman Brent Ross said.
Outbreaks in correctional facilities have been a constant concern since the onset of the coronavirus pandemic.
In April, 60 inmates and eight staff tested positive at the Ontario Correctional Institute in Brampton.
In March, a correctional officer at the Toronto South Detention Center in Etobicoke tested positive for COVID-19 and was treated in hospital.