Some staff in a diagnostic department at St. Boniface Hospital have been sent into self-isolation after a co-worker tested positive for COVID-19, CBC has learned.

A memo was sent Tuesday by Shared Health Manitoba to all staff at the hospital, informing them an employee who works in the echocardiography department tested positive for the disease associated with the novel coronavirus.

Echocardiograms use sound waves to create images of a patient's heart.

This is at least the third known case of a Manitoba health-care worker contracting the virus.

Earlier on Tuesday, public health officials confirmed a staff member in the Selkirk Regional Health Centre's emergency department has COVID-19. The Manitoba Nurses Union also said Tuesday a Winnipeg emergency department nurse has tested positive.

When asked about the infection status of health-care workers earlier Tuesday, Manitoba's chief public health officer said he could not confirm any specifics.

"We know how this virus is transmitted and the personal protective equipment that is required," Dr. Brent Roussin ​​​​​said.

"We know in other jurisdictions throughout the world there is unfortunately transmission that can take place in health-care settings and that's why we have as many protocols as we can to protect our staff, which is one of our biggest priorities."

Contact tracing underway at St. Boniface Hospital

Public health, occupational health and infection prevention and control are investigating the case at St. Boniface, the memo says, and are following up with people at risk of exposure.

In the memo, Shared Health said it is notifying individuals who came in close contact to the worker and providing direction to staff on the type of actions or precautions to take:

Staff in the echocardiography department who worked alongside the individual when they were symptomatic are required to self-isolate for 14 days from the last date of exposure on March 25.

Departmental staff who worked closely with the person prior to them showing symptoms but while they were potentially contagious, known as the incubation period, on March 23 and 24, must self-monitor for symptoms and wear a surgical or procedure mask while at work.

Employees in other departments who may have been exposed through periodic visits to the echocardiography department between March 23 and 25 are being asked to self-monitor but do not need to wear a mask.

No patients have been identified as close contacts of the worker, the memo says.

The department is undergoing cleaning, as per protocol, and will return to normal service on Wednesday. It is unclear how the department has been functioning in the meantime.

The memo did not indicate how many hospital staff are self-isolating as a result of the positive test.

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In an email Wednesday morning, a spokesperson for Shared Health said 13 staff members were immediately notified of the positive test result and told to self-isolate. Any staff determined to have had close contact with the individual who tested positive while that person was symptomatic also have been directed to self-isolate for 14 days from the date of exposure.

Arrangements have been made to bring in staff from other locations to ensure continuity of service, the spokesperson said.

Because all elective echocardiographies were suspended last week due to COVID-19, there already are fewer exams that have been performed in recent days as only those considered to be urgent and emergent are being performed at this time, the spokesperson said.

Physicians and other staff who were not contacted by investigators have been advised to report to work as usual.

In terms of additional steps being taken to prevent health-care workers from infection, chief nursing officer Lanette Siragusa said in most cases workers are taking precautions to avoid close contact and droplets.

"The most important thing we can do is to practise social distancing, wash our hands often, stay home when we're sick and wear the required [personal protective equipment] that's appropriate for that situation," she said.

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