As Canada and the world navigates the COVID-19 pandemic, advice from health care experts is constantly evolving as we learn more about the virus and its variants of concern. Gerald Evans, Chair, Division of Infectious Diseases, Professor of Medicine and Medical Director, Infection Prevention and Control, Kingston Health Sciences Centre, and member of the Ontario COVID-19 Science Advisory Table, recently spoke to the Gazette about where we stand in the fight against the pandemic.

What is the COVID-19 pandemic going to look like this fall?

It is uncertain at this point as we are waiting to see the impact of schools returning to in-person learning. At the moment, the fourth wave appears to be muted with no exponential growth, but this could change.

What should be our biggest concern when studying COVID-19 data – ICU numbers or community case counts?

Now that vaccination rates in Ontario are greater than 80 per cent of the eligible population, the number of cases in hospital and ICU are more relevant to understanding any ongoing serious impact of COVID-19. Most community cases and positive tests are less of an issue as the impact of these is reduced in a heavily vaccinated population. Rises in severe cases (hospitalized and ICU) might require a return to earlier stages in the re-opening strategy being used here in Ontario.

Will mandatory vaccinations on university campuses make a big difference this year?

Absolutely. With rates of fully vaccinated persons (faculty, staff, and students) approaching 99 per cent at Queen’s, this will dramatically reduce case numbers and reduce transmission, alongside other measures like masking, amongst the population of persons on campus.

People have questions about the effectiveness of our vaccines against the Delta variant. How effective are they and how do we interpret the data?

All the current vaccines maintain very high efficacy against severe COVID-19 disease (approximately 90 per cent) as well as protection from infection by SARS-CoV-2 (approximately 75 to 80 per cent) due to the Delta variant.

Are there any other variants we should be worried about this fall?

At this time, no other variants exist that can out-compete Delta, which now accounts for more than 99 per cent of all SARS-CoV-2 infections in Ontario and Canada. In addition, there has been no variant yet found that demonstrates vaccine escape.

Will the general population need a COVID-19 booster shot? If so, under what circumstances?

As we move forward the answer to this question will be more apparent. Having said that, it is more rather than less likely that at some point a booster(s) will be needed in most adult vaccine recipients, as we assess the predictability of antibody levels and clinical endpoints amongst those vaccinated. Stay tuned.

Will we see a return of the flu and other respiratory viruses this fall and winter?

Since we have relaxed some Public Health measures with rising vaccination rates, it is almost certain that we will see the re-emergence of other respiratory viruses this fall/winter. This has been observed in various jurisdictions around the world. Seasonal viruses like influenza and Respiratory Syncytial Virus (RSV), which are transmitted by similar routes like SARS-CoV-2 (Droplet/aerosol and contact), have now been described as increasing in countries that have loosened Public Health restrictions. As a result, having a flu shot this fall is even more important than in the past.

Dr. Evans served as guest speaker at the Principal’s Town Hall on Sept. 7, where he, along with other senior leaders, answered many questions from staff and faculty on how we can ensure a safe environment for everyone on campus. The recording is available here.