MONTREAL -- They’re at the centre of many COVID-19 debates, but we’re still missing a lot of information about how the virus affects them.

Kids are the subject of a new study by Montreal researchers, and specifically how many Montreal youngsters really had COVID-19, whether or not they showed it.

But Kate Zinszer, a researcher at the Université de Montreal, is now testing children in four Montreal neighbourhoods to see if they have antibodies for the virus.

"Everybody is talking about the coronavirus, but we still don't know how many children have gotten it,” researchers explain in a video made for the young participants, to help them understand the study.

Antibodies, they say, “are like brave knights ready to fight the bad virus.”

In the first few months of the virus, early research turned into a tentative common wisdom that young children don’t tend to pass along COVID-19.

Now, testing for antibodies is key when it comes to kids, Zinszer believes, to see if it's true that many children were infected without showing symptoms.

“We think a large portion of children are asymptomatic [and] won't be tested, so this will give us a more accurate representation of, you know, the number of children that were actually infected with COVID,” she explained.

Her own son, six-year-old Charlie, is one of the study’s first participants. In the video, he demonstrates giving a blood sample.

The kids in the study will be tested once in the fall and once again at the end of the school year.

“This will provide a better idea of the extent of transmission in children, which will be extremely important for decision-making,” Zinszer said.

Quebec’s Public Health Director, Dr. Horacio Arruda, says any data like this will help the province decide its next steps and what will really be best for children.

“What are the impacts,” he asked, of closing kids’ activities? “We do protect the kids from the disease, but at the same time we do create more problems long-term.”

Zinszer’s study will also look at that question: the mental-health impact of COVID-related restrictions on children and teens. It will do this through a questionnaire filled out by parents.

“We don't have a play-by-play book right now in order to deal with all the different aspects of the pandemic, but we're hoping our study will provide a crucial piece of information with regard to children, schools and daycares,” she said.

The study is funded by the COVID-19 Immunity Task Force, which was launched by the federal government in April.

The task force’s head also says one variable the study will include is race, which is good news to many community leaders who have been asking for race-based data since the start of the pandemic.