EnCORE :
A COVID-19 Seroprevalence Study

COVID-19 has had a tremendous impact on our children, educators and support staff. Thank you for your participation in a study that could positively affect the future.


The EnCORE study is a collaborative research project between the University of Montreal and CHU Sainte-Justine which aimed to estimate the proportion of SARS-CoV-2 infections (the virus that causes COVID-19) in children aged 2 to 17 throughout the pandemic. The study also examined children’s emotional and mental health. A cross-sectional phase of the study previously assessed SARS-CoV-2 infections among school and daycare staff.

A simple antibody blood test helped us better understand how much virus spread or transmission occurred since the beginning of the pandemic. The information collected will helped guide decision-making about prevention strategies while monitoring emotional and mental health in the evolving context of the COVID-19 pandemic.


The seroprevalence study

As of June 2023, we have reached the end of our seroprevalence study! Since its beginning, our results have been shared with the scientific community and decision makers from the local to national level. We are proud to have contributed to scientific knowledge on COVID-19 in children and teens, recognizing the immense challenges that children and families faced during the pandemic, especially at the heights of uncertainty and isolation.

A final note of thanks

We are deeply grateful to all the participants who joined us in this project. A special thanks to the countless parents and children who have shared stories and warm messages of encouragement with our team.

And finally, a very big thank you to our participants: to all the children and teens who bravely agreed to the finger-prick tests and for sharing your experiences and reflections. We are very proud of your contribution to science!

Study results

Do you want to learn more about the seroprevalence study results? The preliminary findings from the five rounds of the study can be found in our study reports.

The EnCORE sub-study

We are also studying the immune response to COVID-19 infections and vaccines over time in children between 2 and 11 years old, by collecting blood and saliva samples. Our recruitment period is now over, and sample collection is coming to an end. Stay tuned to learn more about the results!

School and Daycare Staff

To all the staff of the selected daycare centers and schools, thank you for participating in the EnCORE study! Our recruitment period for the staff survey is now over. The preliminary findings are now available!