Data on deaths in Quebec over the past month seem to confirm that the booster dose reduces the risk of dying from COVID-19. But it does not reduce the risk to zero, particularly in immunosuppressed people.
Posted at 5:00 a.m.
Among people aged 80 and over, figures from the Ministry of Health and Social Services (MSSS) show that doubly vaccinated people have four times less risk of dying from COVID-19 than those who are not adequately vaccinated. The risks are also reduced by eight times for the triply vaccinated. In general, two-thirds of deaths in the last month have occurred in people aged 80 and over. One in five people were at least 70 years old, and the rest were under 70.
The Press obtained the vaccination status of the 1,135 deaths that occurred between December 27 and January 24. Of these, 380 had received three doses. These are concentrated among the people most at risk, targeted as a priority by the booster vaccination campaign.
During this 28-day period, approximately 281 people aged 80 and over who received three doses of the vaccine died from COVID-19, which represents a ratio of 106 per 100,000 population. All ages combined, people aged 80 and over are still clearly the most affected by the virus.
During this same period, 4% of people aged 80 and over were not adequately vaccinated. One-third had two doses and almost two-thirds had received a third dose. Conversely, just 11% of 30-59 year olds had three doses and 76% had two doses.
In Quebec, the MSSS specifies that “since approximately 94% of people aged 60 and over have received at least two doses of the vaccine against COVID-19, it is normal to observe a higher number of deaths among vaccinated people. in absolute numbers. “As the number of people adequately vaccinated increases, the greater the likelihood of seeing cases in vaccinated people is increased relative to the unvaccinated, as disease transmission in the community continues and vaccines are not 100% effective. % against infection, ”says the spokesperson for the Ministry, Marie-Claude Lacasse, on this subject.
The importance of the “immunity boost”
For professor at the School of Public Health at the University of Montreal (ESPUM) Roxane Borgès Da Silva, the figures obtained by The Press “confirm what the scientific literature says about Omicron, that is to say that it is absolutely necessary to seek this third dose to complete its vaccination coverage”. “It’s the only way to get this boost of immunity that allows you to protect yourself and not develop serious symptoms,” she says in an interview.
PHOTO DAVID BOILY, LA PRESSE ARCHIVES
Roxane Borgès Da Silva, professor at the School of Public Health at the University of Montreal
The expert recalls in passing that several of the deaths linked to COVID-19 among Quebecers vaccinated with two or three doses are probably immunosuppressed people, who can notably contract the virus in a hospital environment. “That’s the big confounding variable in all of this. But for the rest, it is very consistent with what we see elsewhere in the world. The rate of 1171 per 100,000 inhabitants that we see [chez les 70 à 79 ans], it’s huge,” she says.
The mortality rate of Quebecers aged 30 to 59 who received three doses is slightly higher than that of double vaccinated. This difference could be explained by the fact that the booster vaccination strategy first targeted immunosuppressed patients, who are much more at risk of complications from COVID-19.
“Really Eloquent” Data
The bell sound is similar for the DD Maryse Guay, professor at the Faculty of Medicine and Health Sciences at the University of Sherbrooke. “This is really telling data. I wonder what we could have better as advocacy for vaccination, ”she breathes.
“It demonstrates very well that with the Omicron variant, of course, vaccination is not very effective in preventing transmission, but extremely effective against death. We could also do the same calculation with hospitalizations, ”says the DD Guay, who recalls that in epidemiology, it is always necessary to “compare proportions” and “relative weights” of populations, and not only absolute figures.
While January isn’t over yet, it’s already the fifth deadliest month of the COVID-19 pandemic in the province. For the Dr Quoc Dinh Nguyen, a geriatrician at the Center hospitalier de l’Université de Montréal, the high number of deaths is due, in part, to the slowness of the Quebec campaign to provide booster doses to people aged 70 and over living outside the institutional care. “I feel like there is a huge number of deaths and hospitalizations that could have been avoided if we had given our third dose sooner,” he explained.
Unlike previous waves, most of those who died were living at home rather than in long-term care homes or private seniors’ residences. Additionally, of those 70 and older who died in the current wave, 22% were unvaccinated and 34.7% had received a third dose of vaccine more than seven days before their death.
With Thomas de Lorimier, The Press, and The Canadian Press