At least 19 million doses of COVID-19 vaccines are expected to expire by the end of the year in Canada, according to data obtained by The Canadian Press.

According to the Public Health Agency of Canada, the central federal inventory currently has 18.5 million doses, including 16.8 million that have an expiry date of 2023.

There are more than eight million additional doses on provincial and territorial stockpiles, according to data provided by health ministries across the country.

The data consulted shows that more than two million doses that are in the provinces and territories will expire by the end of the year.

This number is likely an underestimate since Ontario, New Brunswick and Prince Edward Island have not disclosed the proportion of their doses that will expire by the end of the year. . Ontario alone has 4.8 million doses of the COVID-19 vaccine.

“The Government of Canada, together with the provinces and territories, will continue its efforts to optimize the management of the supply of COVID-19 vaccines and further reduce surpluses and waste of COVID-19 vaccines”, said a spokesperson for the Public Health Agency of Canada via email.

Some of these doses, for example, could be used in COVID-19 vaccination campaigns if the National Advisory Committee on Immunization (NACI) recommends further booster shots “based on evolving science.”

According to the Public Health Agency of Canada, other options could include donating excess doses of COVID-19 vaccine to developing countries or extending the expiration date of some doses if they are still effective. .

According to Dr. Matthew Miller, director of the DeGroote Institute for Infectious Disease Research at McMaster University, a campaign for general population booster shots is still “likely.”

NACI’s current recommendations in the spring target the most vulnerable groups. They include booster shots for people aged 65 and over, as well as other people at high risk of serious complications from the disease, if it has been six months or more since their last dose or an infection to COVID-19.

About 6.7 million of the doses in the federal inventory are bivalent COVID-19 vaccines, which specifically target the Omicron variant and are recommended for booster shots. Provincial and territorial data show that a large proportion of their vaccines are bivalent doses.

A supply of non-bivalent vaccines is still needed for people getting vaccinated for the first time _ with the primary series of vaccines _ and for children under the age of five, say health officials across the country. Over 80% of Canadians have completed their first round of vaccination against COVID-19.

Canada is also “ready” to donate excess doses of COVID-19 vaccines to developing countries, Global Affairs Canada said in an email to The Canadian Press.

He acknowledges that many low-income countries are not demanding as many COVID-19 vaccines as they did at the start of the pandemic, sometimes because they lack the capacity to administer these vaccines.

“The global landscape has moved from a period of limited supply to one where the supply of vaccines currently exceeds demand and capacity to administer,” said Global Affairs Canada.

“The current challenge is therefore not supply, but delivery, distribution and demand in the country,” the ministry said.

Also, time is running out to give doses, as expiration dates are approaching.

“Recipient countries generally request vaccines with a shelf life of at least six months, which is considered a reasonable timeframe to allow for planning deployment,” a GAVI spokesperson said in an email. global vaccine alliance that helps oversee COVID-19 vaccine donations.

So far, Canada has donated more than 25 million doses that have been shipped to 30 countries, the GAVI spokesperson said.

Another possible option to reduce vaccine wastage is to extend the expiry date by manufacturers of vaccines that are approved by Health Canada.

This has happened before in Prince Edward Island, said Morgan Martin, spokesperson for the province’s Department of Health and Wellness.

“Vaccines in our current inventory have varying expiration dates, and are updated if and when the manufacturer gets an extended expiration date,” she pointed out via email as well.

“For example, the current expiration dates for Pfizer’s pediatric and infant vaccines have been extended and do not expire until 2024,” she pointed out.

To determine if a vaccine is still effective after the original expiration date, manufacturers conduct “stability testing,” said Mina Tadrous, assistant professor of pharmacy at the University of Toronto.

“A manufacturer basically lets something age and then tests it in a certain environment,” Tadrous explained. These tests consider factors such as refrigeration to determine if there are any circumstances where the expiration date can be extended.

As COVID-19 vaccines were new products being made in response to an urgent pandemic, there was no way of knowing how long they might last. So they were given “very tight” expiry dates, he said.

As time passes, researchers can see how long and under what conditions vaccine and drug formulations last, Tadrous said, and expiration dates could be revised in consultation with Health Canada.

Despite efforts to use as many COVID-19 vaccines as possible before they expire, there will be waste, Mr. Tadrous and Dr. Miller acknowledged.

This is not surprising given the complexity of the situation, according to them.

“From a national perspective, we would much rather have the problem of having too many vaccines than too few,” Dr. Miller admitted, however.