A nurse prepares a flu shot. The vaccine for the 2019-2020 flu season is now in pharmacies and clinics. (AP Photo/David Goldman, File)

A nurse prepares a flu shot. The vaccine for the 2019-2020 flu season is now in pharmacies and clinics. (AP Photo/David Goldman, File)

Study says flu vaccine protected most people during unusual influenza season

Test-negative method was pioneered by the BC Centre for Disease Control in 2004

Getting vaccinated for the flu may have prevented about six out of 10 people from becoming infected in an early Canadian flu season, says a study involving a network of family doctors who monitored patients in British Columbia, Alberta, Ontario and Quebec.

Dr. Danuta Skowronski, lead author of the study and lead epidemiologist for influenza at the BC Centre for Disease Control, said the study involved about 2,800 patients who were seen by their physicians for a flu-like illness between Nov. 1, 2019 and Feb. 1.

The current flu season was the most unusual in about five years because of an early spike in influenza B as influenza A was circulating across Canada and the northern hemisphere.

Skowronski said the doctors are part of the Sentinel Practitioner Surveillance Network involved in helping to determine vaccine effectiveness. They took nasal swabs from patients who were at least a year old and were seen within seven days of the start of symptoms such as fever, cough and sore throat.

The study, published Thursday in Eurosurveillance, a journal on infectious disease surveillance, epidemiology, prevention and control, found about an equal number of people were sickened by influenza A and B.

“This vaccine prevented about 60 per cent of cases of influenza that would have otherwise occurred in unvaccinated cases,” Skowronski said.

She said vaccination effectiveness was estimated by comparing vaccine coverage of patients who tested negative for influenza versus those who tested positive.

The so-called test-negative method was pioneered by the BC Centre for Disease Control in 2004 and has come to be used globally in place of randomized control trials, which would require a group of unvaccinated patients, an unethical scenario given everyone should get the vaccine, Skowronski said.

READ MORE: Canadian nurses’ unions warn national standards for coronavirus protection too low

“Other countries have now adopted that methodology,” she said. “Collectively, we submit our findings to the World Health Organization. Later this month the WHO will be meeting to decide whether it needs to update the vaccine strains for next season’s formulation,” she said of the virus that changes every year.

“This is good news in that the vaccine is performing better than it has in previous years,” Skowronski said of the findings, adding they highlight the fact that the public should get vaccinated annually to protect themselves against various strains of the influenza virus, especially if they have a heart or lung condition or are in contact with vulnerable people including the elderly.

“If you want to prevent a miserable illness, and influenza is a miserable illness, a vaccine will protect you against that. But that might be an individual decision. For me, it’s really a kind of double tragedy when high-risk individuals experience these severe outcomes and they could have been prevented through vaccination.”

Concerns about the novel coronavirus should create a greater appreciation for influenza vaccines, Skowronski said.

In place of no vaccine for COVID-19, people should rely on conventional public health measures used for other coronaviruses, such as washing their hands and sneezing and coughing into their elbow, she said.

However, she said knowing who will or won’t get the flu is complex and could include issues such as which influenza subtypes were prevalent around the time someone was born, giving them a lifelong immunity to those subtypes.

British Columbia, Quebec and New Brunswick are the only provinces that do not offer publicly funded vaccination for influenza for all residents but provide it in limited cases, including for pregnant women.

The Public Health Agency of Canada said an average of 12,200 people are hospitalized for the flu every year and 3,500 people die of it annually.

It says everyone aged six months and older should get immunized, and the best time for that is between October and December, before the virus begins spreading.

Camille Bains, The Canadian Press

Like us on Facebook and follow us on Twitter.

flu season

Get local stories you won't find anywhere else right to your inbox.
Sign up here

Just Posted

A memorial to Hudson Brooks outside the South Surrey RCMP detachment. (File photo)
Officer who fatally shot Hudson Brooks recounts ‘absolutely terrifying’ incident

Const. Elizabeth Cucheran testified at coroner’s inquest Tuesday morning

xxx
Batting cages decided where Langley baseball training camp was held

Two groups came together after one learned its cages didn’t meet COVID-19 criteria

Langley MLA Andrew Mercier rose in the provincial legislature on Monday, March 1, to praise a planned new rainbow crosswalk in Langley and to provide some historical context (Provincial legislature video image)
MLA Andrew Mercier praises new Langley rainbow crosswalk

‘There is no human right to hate’

Single-family houses like these, under construction in Willoughby, are now 20 per cent more valuable than a year ago, according to recent real estate numbers. (Matthew Claxton/Langley Advance Times)
‘Great Congestion’ hits Langley real estate as buyers vie for houses

Townhouses and single-family homes are in high demand and prices are up

Riverside Calvary Church in Walnut Grove. (Langley Advance Times file)
B.C. is ‘stereotyping’ churches as riskier for COVID than other spaces, lawyer argues

Judge said that freedom of expression, religion are not at issue in the case

Older rental apartments are prime candidates for renovations, and could result in lost affordable housing stock. (Zoë Ducklow photo)
B.C.’s renoviction overhaul a good start, but won’t preserve affordable stock, lawyer says

And still no protection for people who can’t pay rent due to COVID-19

Cannabis bought in British Columbia (Ashley Wadhwani/Black Press Media)
Is it time to start thinking about greener ways to package cannabis?

Packaging suppliers are still figuring eco-friendly and affordable packaging options that fit the mandates of Cannabis Regulations

(Photo by Marissa Baecker/Shoot the Breeze)
B.C. WHL teams to hit the ice with Kelowna, Kamloops hub cities

Kelowna, Kamloops centres chosen to host B.C. WHL teams for 24-game regular season

The machines are akin to ATMs and allow drug users at risk of overdose to get hydromorphone pills dispensed to them after their palm has been scanned to identify its unique vein pattern. (CANADIAN PRESS)
Feds dole out $3.5M for ‘vending machines’ to dispense safer opioids in B.C.

The machines are located in four cities across Canada, including Vancouver and Victoria

Kelowna’s lakefront visitor centre is one of 130 around the province. Tourism businesses have been hardest hit by COVID-19 restrictions on travel. (Destination B.C.)
Tourism, small business getting COVID-19 help, B.C. minister says

$300M grant program has delivered $50 million so far

The incident happened in downtown Castlegar. Photo: Betsy Kline
Castlegar teen recounts stabbing after stranger breaks into grandmother’s house

The unnamed teen survived a terrifying attack Feb. 21

(Black Press file photo)
Agassiz boy, 11, dies from ‘extensive injuries’: Homicide team

Agassiz RCMP were called out Friday to assist with a child in medical distress

Most Read