In the story ‘Flu shot not effective against H3N2 strain’ published in the Lakes District News’ Jan. 21, 2015 issue, last year’s flu vaccine had not been effective against the A(H3N2) strain.
According to Northern Health’s medical health officer Dr. Sandra Allison, one of the biggest challenges in making an effective vaccine is timing.
“Every year the influenza viruses change, and between the time when we select what components go into our vaccine until the time we start our vaccine campaign, there are some changes that continue to happen with the virus,” she explained.
Last year the A(H3N2) strain had mutated, becoming a “distant cousin” to the strain that was already in the flu vaccine and therefore making the vaccine less effective, she explained.
However, Northern Health says this year’s vaccine is expected to be more effective than last year, offering about 30 to 50 per cent effectiveness.
While some people may worry that 30 to 50 per cent is not a significant probability, Allison said there are no interventions in health that are 100 per cent effective.
“It’s much better to be vaccinated and get some protection than to not receive the vaccine and not be protected at all,” she said.
“When I go to a grocery store, I am more than happy to take a 50 per cent discount, and I would definitely like to see a 50 per cent reduced chance of having a severe illness related to influenza,” she added.
According to Northern Health, influenza is not always a harmless illness. For some, such as the elderly, children under six years of age, and people with weakened immune systems, the flu can cause severe illness and even death.
Every year, about 1400 people in B.C. die from influenza and complications of influenza, such as pneumonia.
“The flu is a serious illness, more so than many might realize,” said federal Health Minister, Leona Aglukkaq in a press release. “That’s why it’s important that all Canadians over the age of six months take the necessary precautions to protect themselves and those around them by getting the flu shot.”
The new quadrivalent vaccine, which is gradually being introduced in Canada, is already available in Burns Lake. The quadrivalent vaccine is recommended for groups of children at high risk of influenza-related complications, including those up to 17 years with any chronic health conditions.
While the trivalent vaccine protects against one B strain of the virus and two A strains – H1N1 and H3N2 -, the quadrivalent vaccine contains an extra variety of the influenza B virus.
The quadrivalent influenza vaccines were developed because in the past decade, the influenza B strain component in the available trivalent vaccine has been mismatched to the circulating strain of influenza B in about half of the seasons.
As of Nov. 4, 2015, Pharmasave had administered two quadrivalent vaccines and still had eight available to the public. Rexall had no quadrivalent vaccines available.
As for trivalent vaccines, Pharmasave had 48 vaccines available on Nov. 4, and Rexall had about 100.
The Public Health Agency of Canada says that even if you got the flu shot last year, you should get it again this year as your immunity may have decreased over time. In addition to getting your flu shot, washing your hands frequently with warm, soapy water, coughing and sneezing in your arm, not your hand, and staying home when you’re sick can also help reduce the risk of catching or spreading the flu.
Although there have been some early influenza outbreaks reported in long-term care facilities in the Lower Mainland, there were no influenza outbreaks reported in Northern B.C. so far this season, according to Northern Health.