Two employees at the National Microbiology Laboratory and one of their close contacts have tested positive for the coronavirus, staff at the Winnipeg facility were told via email on Thursday.

The three are now in isolation, lab executive director Steven Guercio said in the email, which was obtained by CBC News.

"Manitoba Health has initiated contact tracing," Guercio said, referring to the practice of finding out everyone an infected person could have contacted prior to their test.

"As a proactive measure, Facility Occupational Health and Safety has initiated a risk assessment and will ask potential at-risk contacts to isolate at home pending full contact tracing by Manitoba Health," Guercio added.

"Close contacts identified through contact tracing will receive direction from MB Health on testing and isolation requirements."

Guercio also told staff the lab's management "understands that this news will create concern," and advised them to contact employee assistance if needed.

All staff were also instructed to wash their hands on their way out of the building.

Close contacts tested

Guercio's office deferred comment to the Public Health Agency of Canada (PHAC), which is responsible for the microbiology lab.

A Manitoba Shared Health spokesperson did the same, adding the province only comments on infections when there is a public health concern.

A PHAC spokesperson said all procedures for cleaning and disinfection of work areas and common spaces have been followed.

Employees continue to practise effective public health measures, including physical distancing, hand washing and respiratory etiquette, Eric Morrissette said in an email statement.

"It is not unexpected that we would see cases amongst our workforce as COVID-19 infection is circulating in our community," he said.

PHAC has contingency plans to make sure the lab's essential operations can continue, even with sick or absent employees, and employees who have asked to work from home — and who are able to do their duties remotely — are doing so.

"We wish our employees a speedy recovery and are thinking of them and their families during this difficult time," Morrisette said.

The head of the union representing scientists and researchers doesn't know if any of the infected people are her members, but Debi Daviau said she's been told at least one is a lab worker.

Daviau, president of the Professional Institute of the Public Service of Canada, said Health Canada has done contact tracing on all three — any close contacts were tested and sent home, and are expected to get their test results tonight or tomorrow.

Non-close contacts were asked to stay at work for now but they were also tested. If they are positive, they will be sent home for self-quarantine.

Research includes coronavirus

Work at the lab includes research on SARS-CoV-2, the coronavirus that causes COVID-19.

Researchers are trying to find an appropriate animal model for research as they work on a vaccine and treatment for the respiratory illness, Daviau said.

They are also doing research on how to sterilize N95 masks for reuse.

"They are working around the clock. Their work is critical. They are working with the virus, so the potential for exposure is high," she said.

"These members are some of Canada's unsung heroes."

The NML had arranged for a drive-thru testing site at the lab for staff and their families, Daviau said, adding PHAC is handling the situation well.

"PHAC responded rapidly, and fortunately, due to onsite infectious disease experts, they've implemented responsive testing, tracing and isolation measures. We appreciate the urgent action and support for the safety of the employees at the site," she said.

Some staff at the lab have chosen to work at home during this time, but Daviau said others have told her "the work is too important" to close the building.

Meanwhile, the union representing staff including lab technicians as well as building operations, administrative and program staff is waiting to find out if any of its members have been infected.

"Our concern is, first and foremost, the health and safety of our members and all employees at the NML," Shimen Fayad, acting national president of the Union of Health and Environment Workers, said in an email.