SASKATOON -- Duke University in the U.S. is testing Pfizer-BioNTech’s coronavirus vaccine on approximately 2,000 children between the ages of 12 and 15 years old, including Caleb Chung, the teenage son of a doctor.

“I definitely wanted to be part of it in order to show that the vaccines are safe for children and progress the development of the vaccine for young people,” Chung told CTV News Channel during a joint interview with his father from North Carolina on Wednesday. He said getting the vaccine gives people “an extra layer of protection.”

Chung is hopeful the trial will help bring the global population one step closer to achieving herd immunity – which is when most of a group becomes immune to an infectious disease, thereby providing indirect protection to those who can’t take the vaccine.

Chung doesn’t actually know if he’s indeed been vaccinated, as he’s part of a “double-blind” vaccine trial in which neither researchers nor the participants know who received a placebo or the vaccine.

“We’re hoping that I got the real vaccine,” the 12-year old chuckled.

He noted after both the first and second shot- - which were administered at least three weeks apart -- he had some mild headaches, muscle pains around the injection site, and some fatigue, all common side effects for those who’ve taken the vaccine, according to U.S.’s Centres of Disease Control and Prevention.

Children made up at least one in 11 of all reported U.S. coronavirus cases, according to research released in November.

Although COVID-19 cases are milder and reported far less frequently among children, data suggests trends in new cases in the U.S. rise and fall at the same times as in adults. It should also be noted that, between May and September, the average weekly incidence of COVID-19 was twice as high among children aged between 12 and 17 years old, compared with those aged 5 to 11, according to research published in the fall.

Before agreeing in December to be part of the university’s research, Chung admits he was “a little hesitant at first because I didn’t know much about these kinds of trials.”

So he spent a couple of days of familiarizing himself with the requirements of the trial, reading over the informed consent documents, and familiarizing himself with then-recently released data demonstrating the vaccines’ effectiveness in adults.

Before vaccines are approved by government regulatory bodies, such as Health Canada or the U.S. Food and Drug Administration, drugmakers have to demonstrate both efficacy and safety in vaccine trials. But the majority of the trials done so far have been in adults, so data is more sparse when it comes to their efficacy on participants 18 years old or younger.

Chung’s decision hits close to home for his father and pediatrician Dr. Richard Chung who told CTV News Channel, “I had the great fortune of actually working alongside the doctors who are overseeing the trial here in North Carolina.”

As part of his profession as director of adolescent medicine at the Duke University Health System, Dr. Chung works with teenagers and believes “they can and should make decisions and really participate in these things.”

So he was instrumental in bringing home information on the trials and informed consent papers for his son to read through and find out if he’d be interested in being a vaccine participant.

Although “Caleb is pretty into science,” his father said he was “definitely cautious about not pressuring or coaxing him too much.” He noted trials like this one will greatly help researchers gather more data on the vaccine’s efficacy in young people.

“They actually need kids to participate. You can have all the resources [and] the most brilliant scientists but if you don’t have participants who are brave and courageous in this way, the trials can’t work,” Chung said. “So I’m definitely proud of him and the other participants.”