Recent findings from McGill University underscore the necessity of annual COVID-19 vaccine booster doses for immunocompromised individuals, highlighting the ongoing risk of breakthrough infections despite prior vaccinations.

The comprehensive study targeted individuals suffering from immune-mediated inflammatory diseases (IMIDs), such as rheumatoid arthritis, lupus, inflammatory bowel disease, and multiple sclerosis, which collectively affect over seven million Canadians. These patients often face a diminished response to vaccines due to their underlying conditions and the immunosuppressive therapies they typically receive, leaving them more vulnerable to COVID-19 infections.

Published in the journal *Vaccines*, the research indicated that 15% of IMID patients contracted COVID-19 at least once during the study’s duration of one year. Notably, those with elevated levels of a specific vaccine-induced antibody demonstrated significantly lower infection rates, affirming the critical role of booster doses in preserving strong immunity.

“Our findings highlight the importance of booster doses, as immunity diminishes over time,” stated Professor Sasha Bernatsky, a key researcher involved in the study. “Maintaining elevated antibody levels is likely essential for safeguarding against infections.”

Interestingly, the occurrence of past COVID-19 infections did not significantly influence the likelihood of subsequent breakthrough infections among study participants. “This serves as an important reminder that previous infections do not guarantee lasting immunity,” Bernatsky cautioned.

To inform vaccine recommendations in Canada, the research team meticulously monitored 366 IMID patients across the country, predominantly in Quebec. Utilizing saliva PCR tests and antibody assessments provided a more accurate reflection of infection risks compared to relying solely on self-reports or hospitalization records.

Historically, clinical trials for COVID-19 vaccines largely overlooked immunocompromised patients, creating a knowledge gap that warranted investigation. In response, the Public Health Agency of Canada and the COVID-19 Immunity Task Force commissioned this extensive study, which ultimately supports the ongoing recommendation for annual vaccine boosters, five years after the pandemic’s onset.

“While initial mRNA vaccines delivered remarkable efficacy in preventing severe illness, the emergence of new variants and the waning of immunity have led to increased breakthrough infections,” Bernatsky warned. “COVID-19 continues to represent a significant cause of hospitalization, particularly for vulnerable populations. We must now consider it a recurring seasonal threat, much like influenza.”

The collaborative research involved various institutions, including McGill University, the Research Institute of the McGill University Health Centre, the University of British Columbia, Université Laval, McMaster University, Mount Sinai Hospital, the University of Manitoba, and the Canadian Arthritis Patient Alliance.

Looking to the future, investigations examining the efficacy of newer vaccine strategies among IMID and other immunocompromised patients are currently in progress at The Institute, led by an expert team including Ruth Sapir-Pichhadze, Inés Colmegna, and Arielle Mendel, among others.

Stay informed and protect those who need it most—annual COVID-19 booster shots are not just a recommendation; they are a vital part of safeguarding our health in an evolving pandemic landscape!