This year's flu vaccine is far more effective than last year: study

This year’s current flu vaccine is proving to be far more effective than last year’s, according to a mid-season report released by the Canadian Sentinel Practitioner Surveillance Network (SPSN).

The organization, which is headquartered at the BC Centre for Disease Control (BCCDC), measures just how effective each year’s influenza vaccine is.

This year’s report is showing that the 2018/19 influenza vaccine is 72% effective against the H1N1 virus, which is this season’s dominant strain.

Compared to last year’s vaccine, it’s also drastically more effective. During the 2017/18 flu season, in which the dominant virus was a strain of H3N2, effectiveness was at a 17% low. Looking back even further, 2016/17’s influenza vaccine was only 42% effective.

Danuta Skowronski, the lead researcher for the influenza team at the BCCDC, explains that although viruses are very difficult to predict, researchers were anticipating and ready for an H1N1-dominant season.

“It’s difficult to predict, but we had two back-to-back H3N2 epidemics from 2016 to 2018,” she says. “Population immunity helped keep H3N2 suppressed.”

“A vaccine effectiveness of about 70% means for every 10 cases of influenza in unvaccinated people, the number would have been reduced to just three cases if they had been vaccinated,” explains Skowronski.

The recently published report will also help researchers made decisions when determining next year’s vaccine. The SPSN measures data submitted from hundreds of general practitioners in Alberta, British Columbia, Ontario, and Quebec.

Although this year’s flu season is already on the downswing, Skowronski explains that it’s not too late for people to get vaccinated.

The H1N1 virus typically has a greater effect on children and non-elderly adults. The H3N2 virus will usually be harder on the elderly.

The BCCDC reminds people that general hygiene practices such as washing your hands, coughing and sneezing into your elbow, and refraining from touching your face, are also steps that can minimize sickness.