Longer intervals between Comirnaty (Pfizer) vaccine doses may produce better immune responses
In this CITF-funded study led by Dr. Deepali Kumar of the University Health Network, Toronto, researchers followed healthcare workers (HCW) who received the Pfizer Comirnaty vaccine.
Study measures vaccine effectiveness against Omicron infection in Ontario
In a not yet peer-reviewed pre-print study led by CITF-funded researcher Dr. Jeff Kwong on behalf of the Canadian Immunization Research Network (CIRN), researchers evaluated the effectiveness of mRNA (or combined mRNA and AstraZeneca’s Vaxzevria) vaccines in preventing symptomatic infection and severe outcomes caused by the Omicron variant in Ontario.
Latest Canadian Blood Services data reflect uptick in infections prior to Omicron surge
Remarkably, nearly all Canadian Blood Services blood donors sampled in November tested positive for antibodies against the SARS-CoV-2 spike protein. While this was mainly due to vaccination with at least one vaccine dose, seroprevalence from a prior infection with COVID-19 stood at 5.1%, higher than what was seen in previous months. In a subset of repeat donors, new infections occurred mostly in individuals not [...]
Boosting immunity in older people
In this study, led by CITF-funded researchers Drs. Andrew Costa and Dawn Bowdish at McMaster University and published in JAMDA, people in retirement and nursing homes were sampled to measure antibody mediated immunity after the second and third doses of mRNA SARS-CoV-2 vaccines.
The COVENANT Study: COVID-19 cohort studies people experiencing homelessness in Toronto
Non-peer-reviewed data from the CITF-funded COVENANT Study, exploring the impact of SARS-CoV-2 among populations experiencing homelessness in Toronto, found the majority of participants (80%) reported being vaccinated by September 2021, with 79% of them having two doses. 14% were hesitant to be vaccinated. The results were given by study lead Dr. Stephen Hwang, from the University of Toronto and Unity Health, as part of [...]
COVID-19 vaccine uptake in people with autoimmune diseases in Ontario
This CITF-funded study, led by Dr. Sasha Bernatsky from the Research Institute of the McGill University Health Centre and published in the Journal of Rheumatology, found that the proportion of people with autoimmune diseases who had received two vaccine doses was higher (83.8-88.2%) than in the general population (77.9%).
Incarcerated individuals face an increased risk of acquiring COVID-19
Congregate settings (such as prisons, long-term care homes) have provided opportunities for COVID-19 to flourish. As part of her CITF-funded work, Dr. Nadine Kronfli from the Research Institute of the McGill University Health Centre studied a cohort of incarcerated men at three provincial prisons in Quebec.
Vaccination is more effective than prior infection at neutralizing variants of concern
CITF-funded researchers Drs. Sharon Straus, Allison McGeer, and Anne-Claude Gingras, all at the University of Toronto, are among those who contributed to this manuscript characterizing the ability of antibodies acquired via immunization, infection, or both, to neutralize Omicron.
Estimating pre-pandemic rates of certain medical conditions to help inform current COVID-19 vaccine safety surveillance
To help inform vaccine safety monitoring efforts, a team led by CITF-funded researcher Dr. Jeff Kwong from IC/ES, tracked the incidence of nine different medical conditions in the five years preceding the pandemic (2015-2019) and in the first year of the pandemic (2020).