The news this week that hundreds of doses of H1N1 vaccine in Canada had to be discarded because it had expired isn't what many Canadians wanted to hear. But it's just another indication of the need for a thorough review of the country's H1N1 immunization strategy once the current pandemic is finally over.

Health authorities across the country said this week that close to 500 doses of the H1N1 vaccine in Toronto and about 80 doses in Halifax had to be thrown out because of miscalculations. Once the vaccine is in the syringe, it has about a 24-hour shelf life, and if the numbers who show up for immunization fall short of the vaccines drawn, the excess supply has to be disposed of. Nova Scotia's health officer conceded this must be frustrating for those still waiting for immunization, but said officials are trying to limit the waste as much as possible.

No doubt there is frustration, especially since many Canadians have been waiting even longer than originally scheduled for their turn to get immunized. That some vaccines are being thrown out, albeit for safety reasons, is unfortunate. And it's one more thing to add to the list of things to review.

This is the largest mass immunization program in the nation's history, and no doubt there are many lessons to be learned. What worked and what didn't work at the clinic level, such as the protocol for drawing vaccine, is one example.