TORONTO -- The University Avenue laboratory of Public Health Ontario, which provides testing for a variety of diseases including COVID-19, has an outbreak of its own, the agency confirmed to CTV News.

More than a dozen people were infected in the downtown Toronto laboratory in the MaRS Centre, only about 100 meters from Queens Park, as experts raised questions about potential breaches of protocol that may have made that possible.

“As of this morning, 19 Public Health Ontario laboratory employees have tested positive for COVID-19, and all are currently recovering at home,” said the agency in a statement to CTV News on Friday.

“PHO is working closely with Toronto Public Health and following their recommendations as they continue to investigate these cases,” the statement says.

Dr. Anna Banerji of the Dalla Lana School of Public Health wondered whether this is an incident of community spread, or whether the disease was somehow acquired through an infection from laboratory tests itself.

“I think this is an airborne virus and it’s more infectious than we give it credit for. There’s no surprise it’s in a public health lab,” said Dr. Banerji.

“And if this is airborne maybe they need different kinds of precautions,” she said.

Public Health Ontario said that the outbreak is among a small subset of its around 1,000 employees, and said its laboratory testing regime has not been interrupted.

The Public Health Ontario lab is among a growing number of workplaces affected as Toronto’s workplace infection count rises to 60, including a chocolate manufacturer, a car dealership, and three Canada Post sites, including a depot on Ray Avenue and an ongoing outbreak on Eastern Avenue.

Memory is still fresh from the deadly Canada Post Gateway outbreak that infected hundreds and left at least one dead, with the union telling CTV News that it’s long past time to vaccinate postal workers who work in mail-sorting facilities.

“We will continue to take all necessary actions to make sure Canada Post is prioritizing the health and safety of members,” said Jan Simpson, the CUPW national president. “These outbreaks highlight the importance of getting postal workers vaccinated as soon as possible.”

Variants of concern are driving much of the spread. Public Health Ontario also confirmed late Friday that 36 cases of the B.1.617 variant that was first detected in India were discovered in Ontario in the last few days, a day after flights from India and Pakistan were temporarily banned.

Public health officials urged people to stay home, as asymptomatic spread is still a possibility.

“You don’t know if you’re a super spreader,” said Dr. Brenda Coleman of the Canadian Immunization Research Program. “There are too many people that may have silent infections. You could be the problem.”