December 4, 2020
Modelling Demonstrates Restrictions Necessary to Protect Manitobans Against COVID-19
– – –Following Rules, Staying Home Key to Bringing Case Numbers to Manageable Levels: Roussin
New COVID-19 modelling released by the Manitoba government shows restrictions were needed to protect Manitobans in November, Health, Seniors and Active Living Minister Cameron Friesen announced today.
“Modelling is used to simulate the spread of COVID-19, how it affects people and the burden it places on the health-care system,” said Friesen. “The models support our planning efforts by highlighting the need for the strong restrictions that were put in place to bring COVID case numbers down.”
The new modelling shows that, without the Critical-level (red) public health restrictions put in place in November, the province was on pace for a worst-case scenario of COVID-19 cases, hospital admissions and extreme demand on intensive care units. It continues to show the necessity of ongoing restrictions to protect vulnerable Manitobans and the health-care system, the minister added.
Since the spring, Manitoba has used an agent-based modelling strategy, which simulates the lives and decisions of 1.4 million people. The model tries to capture all aspects of Manitobans’ social lives and relationships including how each individual’s behaviour can influence the spread of the virus and the impact of different public health measures introduced at different times.
“Modelling helps us better understand how the COVID-19 virus spreads and how we can target public health measures,” said Dr. Brent Roussin, chief provincial public health officer. “This allows us to take steps to prevent periods of extreme growth in COVID-19 activity while balancing the social and economic impacts on Manitobans.”
The model generates four scenarios, each depicting a level of public health restriction, a level of compliance with public health orders and a resulting level of COVID-19 activity:
• scenario one – extreme: minimal public health restrictions are introduced and compliance with basic public health recommendations is low, resulting in significant COVID-19 activity, including a rapid rise in cases;
• scenario two – severe: some public health restrictions are introduced but compliance with fundamental public health recommendations remains low, resulting in increased cases though at a less rapid rate than scenario one;
• scenario three – moderate: additional public health restrictions are implemented and compliance improves, with individuals beginning to adhere to fundamental public health recommendations, resulting in a level of COVID-19 activity which, if sustained, is manageable for the health system; and
• scenario four – controlled: strong public health restrictions are put in place and compliance is observed as individuals follow the fundamental public health recommendations, resulting in the lowest possible level of COVID activity.
“Our case numbers over the last several weeks have strained the health system and required the introduction of very restrictive public health measures,” said Roussin. “The actual daily data shows that without these measures, our cases would have been even higher, with significant consequences for our health system and the mortality of our most vulnerable citizens.”
The model shows that Manitoba case numbers, particularly in recent months, have followed the ‘extreme’ scenario, with projections of daily case counts reaching as high as 1,055 new cases a day without the implementation of far-reaching restrictions.
“Over the past few days, while we have seen COVID-19 case numbers drop down a bit within the projected range of case numbers, we are not out of the woods yet and must remain vigilant to prevent another spike,” said Roussin.
The models show hospital admissions in the upper end of scenario two, with projections of COVID patients regularly accounting for at least 50 per cent of intensive care unit (ICU) occupancy by the end of the year.
“Our health system and staff remain strained under the current demands of COVID-19, forcing the postponement or cancellation of procedures, appointments and surgeries as staff and resources have been redeployed to prepare for a surge of COVID-19 patients,” said Lanette Siragusa, chief nursing officer, Shared Health.
Detailed acute care planning, helped by physician and staff reassignment and redeployment, has allowed the health system to operate at 126 per cent of capacity from normal, pre-pandemic levels, Siragusa added. The expansion in critical care is even more evident, with planning underway to accommodate up to 173 ICU patients, which is 240 per cent of normal, baseline capacity.
“Some Manitobans may feel they are not vulnerable to the most severe impacts of this virus. However, they need to understand our health system must care for all Manitobans in need of health services, not just those with COVID-19,” said Siragusa. “Nearly half our ICU beds are caring for COVID patients right now. Continued action is necessary to reduce the spread of this virus, and ensure we do not push our health system and our health-care providers beyond their capacity to treat not just COVID-19 patients but any Manitoban who needs care at this time.”
The chief provincial public health officer noted that based on this modelling, Manitoba is not yet seeing significant and sustained downward changes to case numbers under the recent public health interventions on hospital admissions. To ensure COVID cases do not overwhelm the health system’s ability to respond, he noted the public health orders will likely need to remain in place.
“Manitobans themselves have the most important role in determining how successful these measures will be doing our part to reduce COVID-19 cases,” said Roussin. “By following the public health measures in place, looking at ways to celebrate the holidays differently this year, staying home as much as possible and reducing our close contacts, we hope to be able to achieve manageable levels soon, and begin to ease restrictions in place.”
For more information on COVID-19 in Manitoba, visit www.manitoba.ca/COVID19.
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