Alberta's hospitals have seen more than a dozen COVID-19 outbreaks since the pandemic began

On Thursday, a fifth patient at the Foothills Medical Centre died from a COVID-19 infection as the Calgary hospital continues to battle outbreaks.

It's the latest death reported as a result of outbreaks at Alberta hospitals. Since the beginning of the COVID-19 pandemic, 181Albertans have been infected with COVID-19 through outbreaks at hospitals, leading to 17 deaths.

Craig Jenne, an associate professor in the department of microbiology, immunology and infectious diseases at the University of Calgary, said the presence of COVID-19 in hospitals is nearly unavoidable.

"It's nearly impossible if there's virus in the community to guarantee it doesn't enter the hospital," Jenne said. "You can increase vigilance and surveillance, and it may help.

"But we have to really focus on also getting the risk down, so that there's less virus in the community, and less odds of it coming through the front doors."

Numbers provided to CBC News from Alberta Health Services list the number of lab-confirmed cases of COVID-19 in closed outbreaks at Alberta acute care facilities:

• ClaresholmGeneral Hospital, Claresholm: 2 cases, 0 deaths
• Foothills Medical Centre, Calgary: 11 cases, 0 deaths
• Peter Lougheed Centre, Calgary: 16 cases, 0 deaths
• Red Deer Regional Hospital Centre, Red Deer: 2 cases, 0 deaths
• Alberta Hospital, Edmonton: 7 cases, 0 deaths
• Grey Nuns, Edmonton: 2cases, 0 deaths
• Misericordia, Edmonton: 58cases, 11 deaths
• Royal Alexandra, Edmonton: 5 cases, 1 death
• Sturgeon Community Hospital, St. Albert: 4 cases, 0 deaths
• Northern Lights Regional Health Centre, Fort McMurray: 2 cases, 0 deaths
• Queen Elizabeth II, Grande Prairie: 2 cases, 0 deaths

According to information from Alberta Health, outbreaks are publicly reported in acute care and continuing care facilities when there are two or more cases. In such cases, transmission within those facilities has likely occurred.

The numbers provided don't include the evolving situation at the Foothills Medical Centre, which has seen 67 cases in patients, staff and visitors, or the three staff members who have now tested positive at theRoyal Alexandra Hospital in Edmonton.

With its increase in cases this week, the outbreak at Foothillshas surpassed what was Alberta's largest hospital outbreak, at theMisericordia in Edmonton which was temporarily shut down in the summer as a result.

Despite what health officials have called an "aggressive" investigation, they have been unable to pinpoint how COVID-19 made its way into Foothills hospital.Even more puzzling is the fact that the hospital has seen outbreaks on six wards, including several cardiac units.

Site medical director Dr. Peter Jamiesonsaid the hospital isstill trying to uncover any connections

"Those are much more complicated and difficult to confirm," Jamieson said."We believe that within the cardiac units, there are some links."

Albertareported three more COVID-19 deathson Thursday and 173 new cases of the illness.