Thousands of workers at an Amazon warehouse in Brampton, Ont., were ordered to isolate Friday as public health authorities sought to contain a growing outbreak at the facility.
Peel Region's public health unit said everyone working at the site might have had high-risk exposure to COVID-19.
"This is really about trying to make sure that we control spread in our community," Dr. Lawrence Loh, Peel's medical officer of health, said in an interview.
"We had noticed a concerning trend in our ongoing outbreak investigation and that's why we've taken this step now to protect our community and to protect the workers in that workplace."
The public health unit said it had ordered Amazon to suspend all shifts at the 8050 Heritage Road site and have employees self-isolate for two weeks starting Saturday.
The facility employs approximately 5,000 workers, Loh said.
An outbreak began in October and has since been linked to more than 600 cases -- nearly half of those have emerged in the last few weeks, he said.
The health unit felt the need to issue the isolation order as it became clear the outbreak was growing significantly, Loh said.
"There's evidence that those cases are actually spreading outside the contained clusters that have been previously identified," he said.
Several of the recent cases found have involved more contagious variants of COVID-19, although those are not believed to be a key driver of transmission, Loh said.
Amazon has been working directly with the public health unit to address the outbreak but the recent spike in infections was troubling, Loh said, noting that cases in the warehouse were rising even as Peel's community case rate was declining.
The suspension of all shifts at the facility will allow Amazon time to consider operational changes that may prevent future outbreaks, the health unit said.
Employees must isolate until March 27 unless they've tested positive for COVID-19 in the last 90 days and completed their isolation period for that infection, it said.
Loh said his public health unit has asked Amazon to provide workers all the resources they need to self-isolate properly, including paid leave.
A spokesman for Amazon Canada argued that there's little risk of catching the virus within the facility, saying that a recent round of tests came back with a positivity rate of less than one per cent.
"We do not believe the data supports this closure and we will appeal this decision," Dave Bauer said in an email. "This closure may have some short-term impact on our Canadian customers, but we will work to recover as quickly as possible."
Amazon said the employees will be paid while in quarantine, in accordance with company policy.
This report by The Canadian Press was first published March 12, 2021.
This story was produced with the financial assistance of the Facebook and Canadian Press News Fellowship.
Denise Paglinawan, The Canadian Press