Officials in Canada announced Wednesday they had approved the Chinese coronavirus vaccine developed by Pfizer for use on children at least 12 years old, making it the first nation to do so, the Canadian Press reported.

Prior to the announcement, Canada required recipients of the vaccine to be at least 16 years old.

The outlet further reported that the U.S. Food and Drug Administration (FDA) may follow suit within the week and lower the age for receipt. In the U.S., recipients of the Pfizer vaccine must currently be at least 16 years old.

Dr. Supriya Sharma, Health Canada’s chief medical adviser, told reporters that lowering the age of access to the vaccine “will also support the return to a more normal life for our children, who have had such a hard time over the past year.” The move comes after Pfizer, an American company, published a study in March detailing the effects of its vaccine on younger recipients which showed no infections among the roughly 2,200 U.S. volunteers in the 12-15 age range.

Canada’s vaccination campaign has seen roughly one in three citizens receive at least one dose of a coronavirus vaccine. The country has maintained stringent lockdown measures and pursued plans to implement vaccine passport requirements for international travel. Canadian Health Minister Patty Hajdu announced the plan to Canadian radio on Saturday:

Canadians need to be able to have the right kind of certification for international travel because, as we know, Canadians will want to travel internationally, and they will want to make sure they have the right credentials to do that from a vaccination perspective.

Amid the push toward vaccination, the government halted plans to distribute hundreds of thousands of doses of the Johnson & Johnson (J&J) vaccine on Saturday after Health Canada learned the doses came from a Maryland facility the FDA recently flagged for a number of violations, including sterilization failures. The FDA ordered the facility to cease production of the J&J vaccine until it destroyed an estimated 15 million compromised doses. J&J is also an American company.

The Canadian government emphasized its preference that young people receive a vaccine from either Pfizer or fellow American company Moderna, both of which are mRNA vaccines. This type of vaccine injects patients with a protein present on the target virus and teaches the recipient’s body to produce proteins comparable to those the virus creates, thus triggering an immune response without exposing the recipient to the actual virus. Other vaccines, most prominently those currently distributed and produced by China, use the more traditional approach of injecting patients with dead virus cells to trigger responses from the immune system.

Canada’s National Post noted the National Advisory Council on Immunization (NACI) has advised those persons able to wait to receive one of the mRNA options to do so.

“What we’re saying and what we’ve said all along is that mRNA vaccines are the preferred vaccine,” NACI co-chair Dr. Shelley Deeks said. The council recommends only those persons over 30 years old, who are at greater risk, should opt for the vaccines from J&J or AstraZeneca, both of which have been linked to extremely rare instances of blot clotting.

The U.S. Centers for Disease Control and Prevention (CDC) recommended a pause on administering the J&J vaccine in mid-April after six Americans developed rare disorders that led to blood clots and one fatality. A committee from the health regulator has since advocated for reinstating the J&J product. As of April, roughly eight million people in the U.S. had received the J&J vaccine, which requires only one dose.

The AstraZeneca option, which saw considerable use in Europe, has faced suspension of trials and use in the UK, Germany, and Denmark over the blood clot issue. Amid such concerns, the company has also faced somewhat conflicting scrutiny for not producing enough of its product. At least one senior European Union official has blamed the company for the continent’s vaccine supply concerns. The National Post noted that Canada initially contracted with AstraZeneca for 20 million doses but that it has largely used up that supply and has not scheduled any additional shipments or purchases.

The Pfizer vaccine, as of May, remains the most effective product for preventing Chinese coronavirus infections, testing at 95 percent efficacy. The mRNA from Moderna has tested at a comparable 94.1 percent. Other alternative vaccines from China have tested at far lower efficacy levels. Coronavac, developed by the Chinese firm Sinovac, tested at 50.38 percent, just clearing the World Health Organization’s (W.H.O.) bare minimum threshold for approval. Sinopharm’s vaccine, another Chinese option, fared noticeably better at 72 percent efficacy.