Advocates in Toronto are warning an outbreak of the coronavirus among the city's homeless could devastate a population already at risk, and are calling for officials to step up plans to protect them from the virus.

There are no known cases of COVID-19 in homeless shelters or encampments in Canada, nor any evidence of community transmission. So far, all confirmed Canadian cases have been connected to countries that have experienced an outbreak.

But for a population living with crowding, transience and where struggles with addiction and chronic health conditions are especially acute, the spectre of an outbreak poses an "extremely high risk," according to Toronto-based street nurse Cathy Crowe.

"Shelters are like a petri dish waiting for COVID-19 to arrive," Crowe wrote in a recent blog post, saying that, like cruise ships, shelters are especially vulnerable to outbreaks. "Except shelters are more crowded, have even worse ventilation, poorer staffing levels and cleaning standards."

In a given year, some 235,000 Canadians are homeless. In Toronto, the number of people sleeping in shelters each night hovers around 8,000, with occupancy rates regularly reaching 100 per cent.

Crowe and other advocates have long been calling on city officials to declare homelessness an emergency in Toronto — a move that's all the more urgent against the backdrop of COVID-19, she says.

Street nurse Cathy Crowe says the city is not doing a good job of providing adequate shelter for the homeless, especially during winter. (CBC)

"The conditions in the shelters are so severely crowded. Depending on who you talk to, there's maybe 700 to 1,000 people sleeping outside because the shelters are full," Crowe told CBC News. "It's very much linked to the potential risk which is now at our doorstep."

Another street nurse, Roxie Danielson, echoes those concerns.

"I'm extremely worried about this because I know how deadly it could be if it hits the shelter system," said Danielson, who is calling for 2,000 more shelter spaces and for motels to be used for isolation.

Many measures that health-care officials recommend aren't possible for the homeless, who often move from shelter to shelter each night, sleep in close quarters and can't afford to stock up on crucial supplies, says Crowe who has worked with homeless communities for the last 30 years. She was also on the frontlines working with Toronto's homeless during the SARS outbreak of 2003 when, she says on her blog, "we dodged a bullet."

Margaret's Toronto East Drop-In Centre in January 2018, at the height of what advocates deemed the city's homelessness crisis. (Supplied)

'Almost on top of each other'

It's not just the city's official shelter system, either. For three days this past week, the emergency Out of the Cold program — an effort by 16 faith-based organizations that open their doors to the homeless one night each week from November to April — was running at 99 per cent capacity, Rafi Aaron, program co-chair at the Beth Sholom synagogue, tweeted Monday.

On Tuesday, the synagogue closed after a congregant was found to have the coronavirus and so 60 sleeping spaces were lost, Aaron said.

City officials said relocated the program to St. Luke's United Church, about eight kilometres away. But that space's maximum capacity is 35 beds.

Among the measures many advocates are calling for:

Assign a public health nurse to each shelter to reduce demands on staff to screen residents.

Establish what a quarantine protocol would look like.

Increase funding for supplies.

Increased space between beds.

But that kind of spacing is often not possible at respite centres, which aren't subject to the same standards as city shelters, many say.

"What essentially we have here is a health crisis being dropped into a shelter and housing emergency," Aaron said. "People are sleeping and eating almost on top of one another. They are sneezing and coughing on each other."

Crowe points to New York City, which has said city shelters should allow more space between people, put barriers between beds and decrease how many people can congregate at a time.

If we wait for the local transmission to be reported, it will be too late.​​ — Rafi Aaron

Toronto Public Health is working with the federal health agency and Ontario's Ministry of Health to protect the homeless "as new information becomes available," associate medical officer of health Dr. Herveen Sachdeva said in a statement.

The agency says it meets regularly with the city's homeless and housing services — providing advice and help on contingency planning — but did not elaborate on specific measures being taken.

"TPH does not recommend the need for increased cleaning and will advise if any special cleaning processes are recommended," the statement said.

But at Covenant House Toronto, a shelter serving homeless youth, extra cleaning and infection control processes are already underway.

Executive director Mark Aston says its on-site health clinic is currently screening for the virus and key staff are being fitted for specialized masks if infections appear.

"We're certainly doing everything we can," Aston told CBC News. He says Covenant House is preparing for the possible need for quarantine rooms and bathroom, but that details are still being worked out.

The city's health agency has provided his shelter a basic fact sheet about the virus, he said, but so far there's been no specific guidance around COVID-19 prevention.

Street nurse Roxie Danielson is calling for 2,000 more shelter spaces and for motels to be used for isolation. (Nicholas Boisvert/CBC)

"There's no directives for any general screening or additional protocols that are being put forward at this point," he said. Still, he says he's satisfied with the public health agency's approach so far.

"My opinion is I think we need to have trust in Toronto Public Health and the other medical officials who are giving this advice to us."

Many advocates, including Aaron, disagree the city is doing enough.

"We are dealing with a highly vulnerable population... If we wait for the local transmission to be reported, it will be too late."