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       Prime Minister Justin Trudeau chats with people waiting for their shots at a COVID-19 vaccination clinic on July 15, 2021 in Montreal.

       Ryan Remiorz/The Canadian Press

       There are now enough COVID-19 vaccine doses in Canada to fully inoculate everyone eligible, Prime Minister Justin Trudeau announced on Tuesday.

       The federal government hit the critical milestone two months ahead of schedule and after a rocky start to vaccine purchasing in the winter. Since March, the country has moved from drought to deluge in vaccine supply, and the focus has shifted to whether enough people will stick out their arms and help reduce the risks of a fourth wave of the novel coronavirus pandemic.

       “These vaccines work and they’re safe and they’re also available,” Mr. Trudeau told reporters at an event in Moncton, N.B., on Tuesday. “So, with enough doses for everyone, there’s no more excuses to not get your shot.”

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       Between December and March, Canada’s vaccine shipments had not yet totalled 10 million doses. Four months later it now has more than 66 million. That breaks down to enough shots to fully vaccinate more than 33 million people with the two-dose vaccine, covering everyone 12 and over who has been approved for the vaccines.

       Despite a much slower start to vaccinations, compared to countries like Britain and the United States, Canada now leads the world’s major economies in vaccinations, according to the Oxford University website Our World in Data. The achievement comes just weeks before a widely expected federal election call from the minority Liberal government.

       “We have done extraordinarily well. We’re at the top of the world in terms of vaccination processes,” Mr. Trudeau said.

       Despite its progress, though, the country hasn’t yet hit the minimum vaccination coverage needed to avoid overwhelming hospitals in a potential fourth wave and the daily number of doses being administered is dropping. Disease modelling, released in June by the Public Health Agency of Canada, estimated that the country has to hit at least 83-per-cent full vaccination coverage among eligible people to avoid putting too much pressure on hospitals.

       The most recent numbers from the health agency show that as of July 17, 57 per cent of eligible people have been fully vaccinated and 80 per cent of eligible people have received at least one dose.

       Around the world, the Delta variant is driving the latest wave in the pandemic, with a more virulent and transmissible strain of COVID-19 than the original variant. That means that even with 83-per-cent coverage, it’s possible a fourth wave in Canada would still challenge hospital capacity, said Caroline Colijn, a mathematician who specializes in infectious disease at Simon Fraser University.

       She said Canada should be pushing for 90- or 95-per-cent coverage to better protect against COVID-19. “Ninety per cent would be hugely better than 80 per cent. It cuts in half the number of eligible people who aren’t protected,” Dr. Colijn said.

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       Hitting 90-per-cent vaccination coverage is no small task though, and it’s unclear if Canada can hit that high bar by September, said Allison McGeer, an infectious diseases consultant with Toronto’s Sinai Health System.

       “It’s good news that we have lots of vaccine, it’s good news that our vaccination rates are continuing to climb, it’s good news that our case rates are so low,” she said. “What it doesn’t mean, sadly, is that the pandemic is over.”

       With younger children not yet eligible for the vaccine, the introduction of the Delta variant (against which the vaccines are less effective), the pending opening of the border to fully vaccinated travellers and the expected loosening of restrictions, cases are expected to go back up, Dr. McGeer said.

       “It is unlikely that we are going to get through the fall without significant amount of disease,” she said.

       Looking ahead to September and the return of school in Ontario, the province’s medical officer of health reissued his “call to arms.” Tuesday marked exactly 42 days before the start of school, just enough time for eligible students to be fully vaccinated before they return to the classroom, Kieran Moore said at a press conference in Toronto. So far about one third of those kids between the ages of 12 and 17 have not yet received a first dose, Dr. Moore said.

       “It’s a call to arms for all those students who haven’t yet received their first doses to start thinking about it this week. Please,” Dr. Moore said.

       There is a 28-day interval between the shots, and maximum protection only kicks in two weeks after the second dose.

       The Prime Minister urged the remaining people who haven’t gotten a shot to sign up for the vaccine, and pointed out that the vast majority of COVID-19 cases in Canada are happening in people who aren’t vaccinated.

       “The overwhelming majority of cases in Canada are in people who haven’t been fully vaccinated yet,” Mr. Trudeau said. “Only one half of 1 per cent of cases being recorded are in fully vaccinated people.”

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