Scientific publications
Below, you will find several research articles that were published since the beginning of our study. All these scientific publications provide detailed results from our multiple Rounds of data collection. Though our study period has ended, we are continuing to analyze the data collected and publishing research papers about these findings.
Infection-induced seroconversion and seroprevalence of SARS-CoV-2 among a cohort of children and youth in Montreal, Canada
This article published in 2023 presents findings from Round 4.
Key results: Our results show that previously seronegative children were approximately 9–12 times more likely to seroconvert (i.e., become seropositive) during the early Omicron-dominant period (Round 4) compared to pre-Omicron rounds (Rounds 1 to 3). Unlike the pre-Omicron rounds, the rate of seroconversion among 2- to 4-year-olds was higher than older age groups. As seen previously, higher seroconversion rates were associated with ethnic/racial minority status
Seroprevalence of SARS-CoV-2 Antibodies Among Children in School and Day Care in Montreal, Canada
This article published in 2021 presents findings from Round 1.
Key results: The mean seroprevalence was 5.8% but increased over time from 3.2% in October to November 2020 to 8.4% in March to April 2021. Of the 95 children with positive SARS-CoV-2 antibody results, 78 (82%) were not tested or tested negative with RT-PCR testing, and all experienced mild (49 [52%]) or no clinical symptoms (46 [48%]). The children of parents who self-identified as belonging to a racial and ethnic minority group were more likely to be seropositive compared with children of White parents.
Pre-Omicron seroprevalence, seroconversion, and seroreversion of infection-induced SARS-CoV-2 antibodies among a cohort of children and teenagers in Montréal, Canada
This article published in 2023 presents findings from Round 1, 2 and 3.
Key results: The baseline (Round 1) seroprevalence was 5.8%, which increased to 10.5% (Round 2) and 11.0% (Round 3) for the respective follow-ups. The crude rate of seroconversion over the study period was 12.8 per 100 person-years . The adjusted hazard rates of seroconversion by child characteristics showed higher rates in children who were female, whose parent identified as a racial or ethnic minority, and in households with incomes in the lowest tercile of our study population. The likelihood of remaining seropositive at 6 months was 68% and dropped to 42% at 1 year.
Seroprevalence of anti-SARS-CoV-2 antibodies among school and daycare children and personnel: protocol for a cohort study in Montreal, Canada
This article published in 2021 presents the protocol for Rounds 1 and 2 of children’s data collection, along with schools and daycare staff’s data collection.