Publications from our experts

A study by CITF-affiliated experts Drs. Andrew Costa (McMaster University) and Jeffrey Kwong (University of Toronto) assessed the extent of waning immunity among long-term care (LTC) residents in Ontario.

Due to the significant rise in the number of infections during the Omicron period and the widespread adoption of vaccines, a greater proportion of Canadians now have hybrid immunity – defined as immunity acquired from both prior infections and vaccination.

While children have largely been spared from severe COVID-19 disease compared to adults and seniors, some have still suffered serious outcomes requiring medical intervention and hospitalization.

With the arrival of a 7th wave of the pandemic this summer – when we had hoped for some temporary respite from the onslaught of SARS-CoV-2 infections – we approached CITF-affiliated experts for answers to some of the most pressing and perplexing questions about COVID-19.

A recent study demonstrates that a fourth dose of mRNA vaccine was highly effective at protecting residents of long-term care facilities against severe COVID-19 outcomes (86%), symptomatic infection (69%), and any SARS-CoV-2 infection (49%) during the Omicron-fuelled fifth wave.

In this pre-print, not yet peer-reviewed, led by CITF-affiliated researchers CITF-affiliated researchers Dr. Shaun Morris from the University of Toronto and Dr. Fatima Kakkar of the Université de Montréal, along with Dr. Jesse Papenburg (McGill University), Dr. Manish Sadarangani (University of British Columbia), and Dr. Karina Top (Dalhousie University) and other investigators sought to identify factors associated with severe disease among hospitalized children with COVID-19 in Canada.

Long COVID, also known as post-COVID condition, is defined by a wide range of physical and mental health problems that linger for about 4-to-12 weeks after a SARS-CoV-2 infection, and occasionally, longer.

As COVID-19 restrictions are lifted and clinical testing is generally limited to diagnostic purposes in healthcare facilities, the full extent of SARS-CoV-2 infection is largely unknown.

In a study published in CMAJ, CITF experts Drs. David Buckeridge and Mathieu Maheu-Giroux from McGill University and Sharmistha Mishra from the University of Toronto used COVID-19 surveillance data from Jan 23, 2020, to Feb 28, 2021 to identify relevant social determinants of health – those factors influencing health outcomes that go beyond the strictly medical in metropolitan centres in Canada.

Canada has opted to ensure the wide availability of rapid antigen tests for COVID-19. These devices, named for their ability to detect active SARS-CoV-2 infections within one hour, have garnered mixed reviews.