Vaccine cuts risk of influenza illness by about half, BCCDC finds

A new study has found the influenza vaccine is providing substantial protection during this year's early and ongoing flu season.
 
The B.C. Centre for Disease Control said preliminary findings show the vaccine has cut the risk of influenza illness by about half.

 "We will update our analyses in the new year, but these interim findings show a substantial reduction in the risk of influenza illness for vaccinated people who seek medical care." said Dr. Danuta Skowronski, physician epidemiologist at the B.C. Centre for Disease Control (BCCDC).

Skowronski says the flu season's early arrival means they were able to get estimates on vaccine efficacy sooner than normal. 

"It's nice to be able to deliver some good news going into the holiday period," she said.
 
The early findings came from the Canadian Sentinel Practitioners Surveillance Network (SPSN), which is headquartered at the BCCDC and includes hundreds of primary care providers in B.C., Alberta, Ontario and Quebec.

Skowronski says their estimates on the performance of the annually-revised influenza vaccine are sent to the World Health Organization to help it make decisions on future flu vaccines. 

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The majority of flu cases this season have been due to the H3N2 subtype of influenza A, which the BCCDC says is often associated with more severe epidemics and lower vaccine effectiveness compared other types of influenza A or B.

Skowronski said this year's vaccine is providing good protection against the H3N2 subtype.

She notes that older people can have a harder time with the H3N2 viruses. 

"If they haven't been vaccinated yet, now is the time to get vaccinated," she said.

Seniors who want added protection, especially if they have high-risk conditions, may also want to consider having a conversation with their primary care provider about access to treatment options such as oseltamivir, sold under the brand name Tamiflu, according to Skowronski. 

Skowronski says we may be on the downslope of the epidemic curve, but that doesn't mean people should not get vaccinated.

The virus will is likely to be circulating for several more weeks, she said, and social gatherings during the holidays could amplify its spread. She also notes a secondary wave due to influenza B sometimes arrives later in the season.

B.C's Minister of Health, Adrian Dix, is also advocating for those who've yet to be vaccinated against flu to do so now.

"Vaccines are available for everyone six months and older in B.C. and these preliminary findings show how vaccination remains our best defence against respiratory illnesses," he said in a release.

"By getting vaccinated against influenza, you can help protect our public health system and the young children and elderly people around you."