Public health officials are seeing early signs of community transmission of COVID-19 in Winnipeg, Dr. Brent Roussin says.

Officials have not been able to determine the source of transmission for four or five cases in the city, said Roussin, the chief provincial public health officer. 

"We knew to expect this. As more and more cases are introduced into a jurisdiction, community transmission is going to be inevitable," Roussin said Wednesday.

"Now is the time to stay home. I can't stress that enough."

Manitoba has 24 new cases of COVID-19, bringing the province's total to 127, Roussin said Wednesday. Among those patients are two children under the age of five and six people over the age of 70.

Roussin said he could not speak to how the "pop-up cases," or cases with no known transmission chain, were detected.

Manitoba is not conducting mass testing. That means right now, testing is technically only offered to limited groups, including symptomatic people who have travelled outside the province, been in close contact with a confirmed case, or have worked with COVID-19 tests in a lab.

Testing is also offered to symptomatic health-care workers and people who live or work in remote communities or group settings, like correctional facilities, shelters, long-term care or residential facilities and remote work camps. All samples taken from patients with respiratory issues are also getting tested, the province says.

But Roussin said the fact the pop-up cases were caught and diagnosed shows that some of the testing happening involves people outside of the province's strict categories.

"[The diagnoses are] evidence that, even though we have these testing strategies going on, we are testing people in the community that don't actually meet it, or we wouldn't have been able to find these cases," he said.

In coming days, the number of cases is expected to spike, he said. However, he's hoping physical distancing measures put in place in an effort to slow the spread will be effective.

"As we get to this stage, we're likely to see more and more cases daily," he said. "But we're doing all these things to really limit that climb."

Messaging from the province won't change much now that community transmission has been detected, he said. The province has been urging the public to stay home for weeks.

Only go out for necessities, Roussin advised Manitobans. If you must go out, go out alone.

"Stay home, stay home and stay home," he said.

Enhanced physical distancing strategies may be put in place in the future, he added.

Modelling from other countries and the Public Health Agency of Canada has suggested large swaths of the population could become infected. When asked about those models Wednesday, Roussin said Manitoba is doing its own modelling, too.

"But they're all estimates. They're not … carved in stone," he said. "We can do things that can change those estimated numbers, and that's what we're working on now."

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On Wednesday, Roussin confirmed additional health-care workers have been diagnosed with COVID-19, including  workers at Grace and St. Boniface hospitals in Winnipeg.

No patients are believed to have been in contact with those cases, said Lanette Siragusa, chief nursing officer for Shared Health.

But numerous staff members have been identified as known contacts from the St. Boniface site and been sent into self-isolation for 14 days, she said.

"This news is very upsetting to us," Siragusa said. "These cases, though, should serve as a cautionary tale for all Manitobans, including health-care workers."

In response, the province announced new screening procedures to take effect on Wednesday for workers in acute and long-term care facilities.

All staff arriving for the start of a shift must have their temperature taken and answer questions about symptoms, travel history and exposure to positive COVID-19 cases. Staff who are required to come and go during the course of their shift may be rescreened upon re-entry into facilities and service areas.

"We must ensure that we are taking every possible measure to ensure that our staff and our patients are protected," Siragusa said.

On Wednesday, Roussin condemned reports of bullying against people who have been diagnosed with COVID-19 in the province.

He also clarified information released by the province Tuesday that someone with COVID-19 had been at the Club Regent Casino on March 16.

The information was put on the province's website the day after it was informed of the case, he said. He added that risk to other patrons at the casino is considered "very low."

Roussin said he's not aware of any COVID-19 cases in long-term care facilities or correctional institutions.

Starting Thursday, new admissions for adult and youth correctional centres in Manitoba will go through the Winnipeg Remand Centre, the province announced Wednesday. 

Anyone coming into custody will be isolated for up to two weeks to reduce the spread of the illness in facilities, the province said.

Most in-person visits to correctional centres have been suspended, as well as inmate programs, staff training and other group activities. Lawyers are being asked to meet clients remotely whenever possible, but in-person visits with clients can continue everywhere except for the Winnipeg Remand Centre.

The province also is expanding the number of free phone calls for people in custody to stay in touch with their support systems. Cleaning procedures have intensified, including the use of fogging equipment to disinfect large or high-traffic areas.

The province is working on setting up temporary self-isolation options for people who have nowhere else to go, Siragusa said. They're looking at hotels and motels, but are open to other options, she said.

Only people with COVID-19 who urgently need a place to self-isolate will be considered for the temporary sites, Siragusa said.

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