The Public Health Agency of Canada (PHAC) continues to monitor COVID-19 epidemiological indicators to quickly detect, understand and communicate emerging issues of concern. Today, I presented an update on national epidemiology and modelling. The following is a brief summary of the modelling results and latest national numbers and trends.
Today’s updated longer-range modelling forecast suggests the fourth wave could continue to decline in the coming weeks if transmission does not increase. With the predominance of the highly contagious Delta variant, the longer-range forecast continues to reinforce the importance and beneficial impact of public health measures and individual precautions, even at current levels of vaccination coverage. While we are continuing to see positive signs, cases could begin to rise again with only a modest increase in transmission. This suggests that there could be still bumps in our COVID-19 trajectory and the winter months may bring additional challenges as other respiratory infections make a comeback, but we know that individual practices work to reduce infection and protect against severe outcomes from COVID-19 as well as other respiratory pathogens.
Since the start of the pandemic, there have been 1,725,151 cases of COVID-19 and 29,115 deaths reported in Canada. These cumulative numbers tell us about the overall burden of COVID-19 illness to date, while the number of active cases, now at 23,162, and 7-day moving averages indicate current disease activity and severity trends.
Nationally, COVID-19 disease activity is continuing to decline, with an average of 2,231 new cases reported daily during the latest 7 day period (Oct 29-Nov 4), a decrease of 5% compared to the previous week. Hospitalisation and critical care admission trends, primarily involving unvaccinated people, are decreasing nationally but remain elevated. The latest provincial and territorial data show that an average of 1,934 people with COVID-19 were being treated in Canadian hospitals each day during the most recent 7-day period (Oct 29-Nov 4), which is 8% lower than last week. This includes, on average, 595 people who were being treated in intensive care units (ICU), 8% less than last week and an average of 27 deaths were reported daily (Oct 29-Nov 4). Together with prolonged hospital stays these still elevated numbers continue to place a heavy strain on local healthcare resources, particularly where infection rates are high and vaccination rates are low.
During this fourth wave of the COVID-19 pandemic in Canada, infections and severe outcomes have several key features:
• Nationally, the highly contagious Delta Variant of Concern (VOC), accounts for the majority of recently reported cases, is associated with increased severity, and may reduce the effectiveness of vaccines
• Most reported cases, hospitalisations and deaths are occurring among unvaccinated people
• Virus spread in areas with low vaccination coverage presents an ongoing risk for emergence of and replacement by new VOCs, including a risk of VOCs with the ability to evade vaccine protection.
Regardless of which SARS-CoV-2 variant is predominating in an area, we know that vaccination, in combination with public health measures and individual practices, continue to work to reduce disease spread and severe outcomes. In particular, evidence continues to demonstrate that a complete two-dose series of Health-Canada approved COVID-19 vaccines provides substantial protection against severe illness, particularly among younger age groups. Based on the latest data from 12 provinces and territories for the eligible population, 12 years or older, in recent weeks (September 19 – October 16, 2021) and adjusting for age, average weekly rates indicate that unvaccinated people were significantly more likely to be hospitalized with COVID-19 compared to fully vaccinated people.
• Among youth and adults aged 12 to 59 years, unvaccinated people were 51 times more likely to be hospitalized with COVID-19 than fully vaccinated people
• Among older adults aged 60 years or older, unvaccinated people were 19 times more likely to be hospitalized with COVID-19 than fully vaccinated people.
As of November 4, 2021, provinces and territories have administered over 58 million doses of COVID-19 vaccines, with the latest provincial and territorial data indicating that over 89% of people aged 12 years or older have received at least one dose of COVID-19 vaccine and over 84% are now fully vaccinated. Age-specific vaccine coverage data, as of October 30, 2021, show that over 88% of people 40 years or older have at least one dose and over 84% are fully vaccinated, while 84-85% of younger adults aged 18-39 years have at least one dose and less than 80% are fully vaccinated.
As more of our activities move indoors, this fall and winter, we must strive to have as many eligible people as possible fully vaccinated against COVID-19 as quickly as possible to protect ourselves and others, including those who may not mount a strong immune response or who cannot get vaccinated. Implementing timed and targeted public health measures and maintaining individual protective practices will be crucial for slowing COVID-19 infection rates and reducing the impact on healthcare capacity. While our protection against COVID-19 has been bolstered by vaccines, we also need to think about the return of other respiratory infections. We can stay healthier by getting up-to-date with recommended vaccines, such as influenza and other routine vaccines for children and adults and maintaining basic precautions that help slow the spread of COVID-19 as well as other respiratory infections.
While COVID-19 is still circulating in Canada and internationally, public health practices remain crucial: stay home/self-isolate if you have symptoms; be aware of risks associated with different settings; follow local public health advice and maintain individual protective practices. In particular, physical distancing and properly wearing a well-fitted and well-constructed face mask provide additional layers of protection that further reduce your risk in all settings, as well as getting the best ventilation possible in indoor spaces.