MIDDLESEX CENTRE, ONT. -- The COVID-19 case count in Middlesex-London hit 600 on Thursday, with five new cases reported in the region for the third day in a row.

Four cases are in the City of London, with that total climbing to 560.

Middlesex-London Health Unit Medical Officer of Health Dr. Chris Mackie says all the cases are linked to other known cases.

Of the total, 465 have recovered and there have been a total of 57 deaths, though none in recent days.

An outbreak at Chelsey Park Retirement Centre was declared over on Wednesday, leaving just two active outbreaks in the region, at Kensington Village and PeopleCare Oakcrossing.

Long-term care and retirement homes are linked to 176 local cases, including four of the new cases reported Thursday, all four of which were staff at seniors' facilities, including three at one location.

One new COVID-19 case was reported in Sarnia-Lambton as of Wednesday night, raising the total there to 279, with 239 recovered and 25 deaths.

A second outbreak has been declared in Sarnia, this one at Bluewater Health, where three staff members have reportedly tested positive for the novel coronavirus.

One new case was reported in Grey and Bruce counties as of Wednesday, bringing the total there to 102 cases, including 93 recovered and no deaths.

That total includes two presumptive cases that are awaiting confirmation.

There was no change in the numbers for Elgin and Oxford counties reported on Thursday. Southwestern Public Health says the totals held at 82 cases, with 70 resolved and four deaths.

The numbers from Huron Perth Public Health also saw no change Thursday, holding at 57 cases, 49 recovered and five deaths.

Ontario reported some of its lowest numbers in nearly three months, with 173 cases and just three deaths in the last 24 hours.