The Ontario government is moving Middlesex-London Health Unit to the Red-Control level.
The community enters the red zone as of 12:01 a.m. Tuesday. It was previously in the Orange zone.
Officials say from March 22 to 28, 2021, the region's case rate increased by 86.9 per cent, to 64.4 cases per 100,000 people.
The public health region is also reporting an increase in cases screened as variants of concern.
"As a result of worsening trends of key health indicators, our government is taking immediate action to put stronger public health measures in place in the Middlesex-London public health region," said Christine Elliott, Deputy Premier and Minister of Health. "As we continue to see the rates of transmission increase throughout the province, we all must continue doing our part and follow public health measures and advice to stop the spread of COVID-19 and protect our hospital and health system capacity."