OTTAWA -- The federal government has released an updated COVID-19 vaccination timeline, showing that at least 14.5 million Canadians will be able to be immunized by the end of June with the approved Pfizer-BioNtech and Moderna shots.

Both of these currently approved vaccines require a two-dose regimen and the Public Health Agency of Canada鈥檚 timeline indicates that these figures are based on each person receiving both their first and second shots.

The number of Canadians able to be vaccinated in that timeframe will increase considerably, should additional vaccine candidates be given the green light by Health Canada.

The timeline shows that up to 24.5 million Canadians could be fully vaccinated by the end of June, if shots from the other vaccine companies that Canada has deals with that are currently under Health Canada review are granted regulatory approval: AstraZeneca, Johnson & Johnson, and Novavax.

These figures are based on how much vaccine supply Canada will have, and it will be on the provinces and territories to execute a timely administration of these doses. The federal public health agency is also cautioning that the estimates are 鈥渟ubject to change based on the progress of ongoing clinical trials, regulatory reviews, the scale-up of supply chains and ongoing supplier engagement.鈥

The new timeline issued on Thursday shows how many Canadians are projected to be immunized each quarter between now and the end of September. It鈥檚 an update from the initial estimates issued at the start of Canada鈥檚 vaccine rollout in December 2020.

That modelling showed the federal government was aiming to have between 15 and 19 million Canadians vaccinated by the end of June.

During an update on Canada鈥檚 mass vaccination efforts, Maj.-Gen. Dany Fortin said that the change in the figures is due to a few factors, including the federal government securing additional access to more shots earlier in the spring, and that Health Canada has sanctioned vaccine administrators to extract six instead of five doses from Pfizer vials.

Under the current timeline, between 38 and 64 per cent of the population will be immunized by the end of June. Between April and June is what is being considered the Phase 2 of the vaccine rollout, where priority groups will be expanded to include more higher-risk populations. Among those set to be next in line for shots will be individuals in congregate living and work settings, as well as racialized communities.

While Canada鈥檚 vaccine deliveries from Pfizer and Moderna are set to continue increasing in the weeks ahead, there鈥檚 set to be a jump in weekly doses come April, as the government is expecting a combined 23 million doses to arrive from these two pharmaceutical companies between April and June.

鈥淧reparation for this large scale ramp up, the vaccine national operations center continues to work closely with provinces and territories and stakeholders to ensure that they have capacity and capability to keep pace with increasing shipment size of authorized COVID-19 vaccines,鈥 Fortin said Thursday.

Part of this is making sure there are enough freezers and other cold chain equipment to keep the influx of doses stable and available across more administration locations.

鈥淭here's a lot of planning happening in the background,鈥 Fortin said, adding that more freezers will be sent across the country 鈥渋n the next weeks.鈥

MILLIONS WAITING UNTIL JULY

The timeline still shows that millions of Canadians will be waiting until sometime between July and September to receive their vaccines. This is the timeframe the federal government is anticipating eligibility for vaccinations will be opened up even more to the general population, seeing the lowest risk demographics be able to receive their shots.

Should no other vaccines be deemed safe and effective in Health Canada鈥榮 eyes, there will still be enough doses of Moderna and Pfizer alone to complete Canada鈥檚 mass vaccination effort over these summer months.

With those two vaccines, Canada would have enough vaccines to immunize 42 million people by the end of September.

If additional vaccines are able to be used, the country will have enough doses to vaccinate all 38 million Canadians more than twice over, with expected access to enough shots to immunize 79 million people.

However, as things stand these vaccines have yet to be approved for use people under the age of 16, and the federal government is anticipating a degree of vaccine hesitancy in which eligible adults opt not to get a COVID-19 vaccine.

Fortin said Thursday that should other vaccines be approved, it would be a shot in the arm to the logistics side of the rollout as the next two candidates in line for approval from Johnson & Johnson and AstraZeneca don鈥檛 have to be stored at the same degree of cold temperatures that the Pfizer or Moderna shots do.

This would allow provinces to more easily use existing vaccine infrastructure to open up many more vaccine administration sites, like those opened during flu season.

The projections continue to indicate that by the end of March three million Canadians will have been immunized, which represents eight per cent of the population.

Next week Pfizer will be sending 475,020 doses and Moderna will be sending 168,000. In March Pfizer will be sending approximately 2.2 million doses and Moderna will be sending approximately 1.3 million doses.

Deputy Chief Public Health Officer Dr. Howard Njoo said Thursday that even with still a small percentage of the population receiving shots so far, there has been initial indications that in settings like long-term care facilities the vaccine is providing 鈥渁 good increase in terms of the level of protection for residents in these types of settings, even after one dose.鈥