According to the Public Health Agency of Canada, last year was one of the country’s worst flu seasons in decades. The influenza virus contributed to 606 deaths and over 8,000 hospitalizations last season, prompting a revision of the flu vaccine, which has had the same formulation for decades.
The flu vaccine typically consists of three strains of inactive virus that is meant to help your body fight the real illness. This trivalent recipe includes two influenza A strains and one B strain. The vaccine changes slightly each year to address strains of influenza that are determined to be the most prevalent, which is why it is important to get re-immunized each year.
Last year’s flu vaccine was less than 20 per cent effective, according to Global News. Research suggests that the H3N2 flu virus mutated to conceal the infection from the immune system.
This year, a new formulation adds a fourth strain of the virus in an effort to make the publicly available vaccine more effective. Last year saw a mutation in the influenza A-strain as well as a mismatch in the vaccine for one B-strain, which may have contributed to the harsh effects of the virus and the inefficiency of the vaccine. Offering two B-strains in this year’s vaccine will provide broader coverage, and PHAC hopes that cases of influenza will be minimized in this way. However, not all Canadians will be able to receive this new and improved vaccine. PHAC stated that approximately 12 million influenza vaccine doses have been ordered by provinces and territories for this year’s public immunization programs, however only 2.9 million of these will be four-strain vaccines. The decision as to who is eligible for these limited doses is left up to the provinces and territories.
In Ontario, the four-strain vaccine will be administered to children six months to 17 years old, similar to British Columbia and Alberta. Quebec and Saskatchewan are limiting their doses to infants and young children, or older children with compromised immune systems. Other provinces are taking a different approach, administering the vaccine to people of all ages.
Some provinces are waiting to see how effective the four-strain vaccine is in adults before providing it to all residents, because the enhanced vaccine is more expensive. As it provides additional coverage against B-strain infections, some health agencies believe that it will be more effective in young children as they are more vulnerable to this strain of the illness.
Doug Sider, Ontario Public Health’s medical director of communicable disease, told Global News, “The vaccine is always going to help you in any given flu season.”
The three-strain vaccine is still effective, and health agencies continue to urge Canadians to get a flu shot this season.
On campus, Student Health Services will be offering flu vaccine clinics for free by mid to late October. The vaccine is also available for free through your family physician or Wellington-Dufferin-Guelph Public Health. Information about Student Health Services clinics will be available on their website shortly but clinics have not yet been scheduled for 2015.
PHAC estimates that 10-20 per cent of the population becomes infected with influenza each year. This rate is highest in young children but rates of serious illness and death are higher in infants, people over the age of 65, and people with underlying medical conditions.
Some of the most effective ways to avoid the flu are thorough and frequent hand washing, disinfecting shared surfaces, and sneezing or coughing into your sleeve.