Health officials in Alberta say it's still important for people get flu shots, despite indications from Australia that the vaccine may not be effective against this year's predominant strain.
In the southern hemisphere, effectiveness was only 10 percent for H3N2, which is expected to be this year's predominant strain in Alberta.
"There are enough warning signs that the medical system has to be ready," said Dr. Lynora Saxinger, an infectious disease specialist at University of Alberta.
"We can't say we're going to have exactly the same experience, but it is truly a concern that it could be a rough year. Even if you have had your vaccine, you might not see protection against the dominant strain. Although there's other reasons to consider still getting it."
Those reasons include protection against other flu strains, such as H1N1 and Influenza B, which the shot also inoculates against. Saxinger said vaccine efficacy for those strains was between 50 to 60 percent. The flu shot could also reduce the severity of illness for those hit by H3N2, she said.
Asked about Australia's results, Health Minister Sarah Hoffman stressed the importance of getting a flu shot.
"We know that the best way to protect yourself is to get immunized, so I want to continue to encourage everyone to do so here," Hoffman said on Monday.
Alberta Health Services said it's too early to speculate on the effectiveness of this year's vaccine, noting that several flu strains are circulating in Alberta.
"These viruses are not identical to those in the southern hemisphere," AHS spokesperson Rob Gereghty said in an email. "The vaccine also protects against an influenza A H1N1 strain and two strains of Influenza B."
Saxinger said the circumstances will likely prompt more attention and resources towards developing a universal vaccine that would no longer require annual immunization.