May 20, 2022 | Ottawa, ON | Public Health Agency of Canada

The Public Health Agency of Canada (PHAC) continues to monitor COVID-19 epidemiological indicators to quickly detect, understand and communicate emerging issues of concern. The following is a brief summary of the latest national trends.

For additional COVID-19 data and analyses, the PHAC posts the following reports:

• Daily Epidemiological Update,
• COVID-19 wastewater surveillance dashboard
• COVID-19 vaccine coverage data,
• Reported Side Effects Following COVID-19 Vaccination in Canada
• COVID-19 trend reports, including weekly case by case Epidemiological Report

While SARS-CoV-2 virus is still circulating across the country, disease activity indicators continue to show decreasing transmission in most areas. Nationally, laboratory test positivity during the latest 7-day period (May 11-17, 2022) has decreased to 11%. Similarly, wastewater signals have plateaued or are continuing to decline in many areas, however there is considerable variability from testing sites across the country.

Currently, hospitalizations rates remain elevated and variable, but there are signs that severe illness trends are declining as well. Nevertheless, weeks of COVID-19 resurgence including widespread illness and healthcare worker absenteeism has contributed to prolonged impacts on the health system. Keeping infection rates down remains key to protecting vulnerable populations and reducing severe outcomes and overall impact on the health system.

As we expect the SARS-CoV-2 virus to continuously evolve, we are closely monitoring the domestic and international situation and preparing for new variants, including possible recombinant variants that can arise from genetic mixing during co-infection with two variants. Currently, the BA.2 sub-lineage of the Omicron variant remains predominant among sequenced variants in Canada. Because the Omicron variant is immune evasive, two doses of COVID-19 vaccines offer less protection against Omicron than against previous variants. Fortunately, evidence shows that boosters can help increase antibody levels that wane over time after the second dose. Although vaccine effectiveness against infection decreases over time, evidence shows that two doses of mRNA vaccines generally maintain good effectiveness against severe outcomes across variants, and a booster further increases vaccine effectiveness to over 90% against severe outcomes. Thus health authorities continue to strongly recommend up-to-date COVID-19 vaccination for all eligible people, including for those who may have been previously infected.

Currently, over 5.0 million eligible Canadians need one or more doses to complete their primary series and many others are eligible to get a booster dose(s) to help improve protection that may have decreased since their second dose and to provide even better protection against severe illness from Omicron. In particular, getting a booster dose if you are eligible, and especially for those aged 50 years of age or older, is very important, given the risk of severe illness increases with increasing age. As of May 19^th, over 18.6 million third doses and as of May 8^th, over 2 million fourth doses have been administered to date. As well, national data as of May 8^th, 2022 indicate that over 85% of seniors aged 70 years or older and 62%-76% of 50-69 year olds have received at least one additional dose.

During the transition phase of the pandemic and beyond, our best advantage is to continue maintaining caution and a state of readiness as we prepare our surge capacity for future response, while not forgetting the personal protective habits we have learned. At the individual level, this can be best achieved by keeping COVID-19 vaccinations up-to-date, including getting a booster dose(s) as recommended. At the same time, continuing to follow public health advice tailored to local epidemiology and circumstances can help guide your individual and family risk assessment and use of personal protective practices to reduce your risk of exposure and spreading the virus. In particular, properly wearing a well-fitted and well-constructed face mask, avoiding crowding, and getting the best ventilation possible in indoor spaces, are layers of protection that can reduce your risk in all settings.

We can also stay healthier by getting up-to-date with other recommended vaccines and routine vaccines for children and adults. For additional information regarding vaccination in your area, reach out to your local public health authorities, healthcare provider, or other trusted and credible sources, such as Immunize.ca and Canada.ca, which includes information to help Canadians understand the benefits of being vaccinated against COVID-19.

Canadians can also go the extra mile by sharing credible information on COVID-19 risks and prevention practices and measures to reduce COVID-19 in communities.