The updated flu vaccine may work better than last year's did against the H3N2 strain but public health experts once again expect it to underperform.

The updated flu vaccine may work better than last year's did against the H3N2 strain but public health experts once again expect it to underperform.

Flu vaccine to underperform again

Epidemiologist expects less than ideal protection against resurgent H3N2 flu strain but better than 'zero' last year

There are signs the flu season may hit B.C. early and hard and public health officials are warning they expect the flu vaccine to again be less effective than they’d like.

The most dangerous influenza type for vulnerable people is the H3N2 strain that was dominant in last year’s severe flu season.

But because of a genetic mismatch, the vaccine provided last year was useless in warding off H3N2, according to B.C. Centre for Disease Control epidemiologist Dr. Danuta Skowronski.

That component of the vaccine was replaced on orders of the World Health Organization, but preliminary evidence suggests the new version will still not be a good match against H3N2, falling well short of the 60 to 70 per cent protection rates against other flu strains in most years.

“I believe it’s going to be better than last year – in other words I don’t think it’s going to be zero – but by how much, I can’t say,” Skowronski said.

She said there’s good reason to hope it may be 40 to 60 per cent effective overall, adding she continues to recommend the vaccine, particularly for those more vulnerable.

“If you are a high-risk person, especially with heart and lung conditions or elderly, even if you’re looking at vaccine protection of 30, 40 or 50 per cent, you’re still better off than if you’re unvaccinated.”

Flu vaccine will be widely available by November and may be offered sooner than that in high-risk settings like residential care homes.

Epidemiologists had expected H3N2 would be less prevalent this year, with more of a mix of H1N1 and influenza B strains also in circulation, making the mismatch less of a worry.

But Skowronski noted there have already been two H3N2 outbreaks in long-term care homes in B.C.’s Vancouver Coastal health region – one in the summer and another in late September.

“To have had outbreak activity already in the summer is very unusual,” she said. “We are monitoring that closely for the possibility of an early season.”

Apart from last year, B.C. hasn’t seen flu outbreaks this early since 2009.

Last year, with H3N2 widespread and the mismatched vaccine offering no defence, there were 175 outbreaks in long-term care homes.

That was the highest number in more than a decade and twice as many outbreaks as the previous peak year of 2012.

Skowronski acknowledged the mismatch problems threaten to erode public confidence in the flu vaccine but hopes vulnerable patients are not dissuaded.

“For me, it would be a double tragedy, frankly, if coming out of last season our high-risk people lost faith and did not get the vaccine.”

While influenza is a “miserable” illness, Skowronski said it’s not life-threatening to healthy people, for whom vaccination is still encouraged but a matter of personal preference.

About one-third of B.C. residents typically get the flu vaccine each year.

H3N2 vaccines have consistently underperformed in recent years.

Skowronski said more work is needed to try to solve the challenges of accurately gauging the vaccine’s fit against the virus in the lab, and in effectively reproducing a well-matched vaccine without losing its properties.

Also requiring more research, she said, is emerging evidence suggesting repeated use of the vaccine by a given patient diminishes its effectiveness for them in future years.

While the flu vaccine may not perform as well for someone who also received it the previous year as it would for a first-time user, Skowronski said, they’ll still be better off than unvaccinated people.

Her team is trying to recruit more B.C. doctors and nurses to help track the spread of flu strains this year and monitor the effectiveness of this year’s vaccine.

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

Just Posted

Sidney Jon Blair said he would have died if a van and car had collided at the intersection of corner of Resthaven Drive and Brethour Avenue in early December. (Wolf Depner/News Staff)
Sidney senior urges motorists to slow down on Resthaven Drive

Jon Blair said community must become more pedestrian-friendly

Tarpaulin-covered tents sit next to one of the ponds in Beacon Hill Park. The location of the Meegan community care tent has still not been nailed down, as Victoria council rejected the recommendation offered by city staff. (Don Descoteau/News Staff)
Location of care tent for Victoria’s Beacon Hill campers still not settled

Council roundly rejects Avalon Road site, road’s edge on Cook Street appears the top alternative

Bob Joseph, author of 21 Things You May Not Know About the Indian Act, will be available for a Q&A through the Vancouver Island Regional Library Jan. 28. (Courtesy of Vancouver Island Regional Library)
Q&A on the Indian Act with Bob Joseph open to Greater Victoria residents

Bob Joseph is the author of 21 Things You May Not Know About the Indian Act

Coaches with the Juan de Fuca Minor Hockey association have had to get creative during their weekly practices to keep players interested and improving their skills without physical contact. (Damian Kowalewich photo)
West Shore minor hockey coach shares what it’s like on the ice without parents, fans

Most practices consist of relay races, goalie shots and passing drills

The Songhees Wellness Centre is a symbol of First Nations strength in the region. Representatives of local First Nations will soon play a greater role in decision making and governance relating to the Capital Regional District. (Courtesy Royal Roads University)
Capital Regional District to add First Nations representatives to advisory committees

Board approves bylaw, looks forward to Indigenous input on future decisions

A scene from “Canada and the Gulf War: In their own words,” a video by The Memory Project, a program of Historica Canada, is shown in this undated illustration. THE CANADIAN PRESS/HO - Historica Canada
New video marks Canada’s contributions to first Gulf War on 30th anniversary

Veterans Affairs Canada says around 4,500 Canadian military personnel served during the war

A 17-year-old snowmobiler used his backcountry survival sense in preparation to spend the night on the mountain near 100 Mile House Saturday, Jan. 16, 2021 after getting lost. (South Cariboo Search and Rescue Facebook photo)
Teen praised for backcountry survival skills after getting lost in B.C.’s Cariboo mountains

“This young man did everything right after things went wrong.”

Conservative Leader Erin O’Toole holds a press conference on Parliament Hill, in Ottawa on December 10, 2020. THE CANADIAN PRESS/Sean Kilpatrick
No place for ‘far right’ in Conservative Party, Erin O’Toole says

O’Toole condemned the Capitol attack as ‘horrifying’ and sought to distance himself and the Tories from Trumpism

A passer by walks in High Park, in Toronto, Thursday, Jan. 14, 2021. This workweek will kick off with what’s fabled to be the most depressing day of the year, during one of the darkest eras in recent history. THE CANADIAN PRESS/Chris Young
‘Blue Monday’ getting you down? Exercise may be the cure, say experts

Many jurisdictions are tightening restrictions to curb soaring COVID-19 case counts

A health-care worker prepares a dose of the Pfizer-BioNTech COVID-19 vaccine at a UHN COVID-19 vaccine clinic in Toronto on Thursday, January 7, 2021. THE CANADIAN PRESS/Nathan Denette
COVID-19: Provinces work on revised plans as Pfizer-BioNTech shipments to slow down

Anita Anand said she understands and shares Canadians’ concerns about the drug company’s decision

Tourists take photographs outside the British Columbia Legislature in Victoria, B.C., on Friday August 26, 2011. A coalition of British Columbia tourism industry groups is urging the provincial government to not pursue plans to ban domestic travel to fight the spread of COVID-19. THE CANADIAN PRESS/Darryl Dyck
B.C. travel ban will harm struggling tourism sector, says industry coalition

B.C. government would have to show evidence a travel ban is necessary

(Phil McLachlan - Capital News)
‘Targeted’ shooting in Coquitlam leaves woman in hospital

The woman suffered non-life threatening injuries in what police believe to be a targeted shooting Saturday morning

Everett Bumstead (centre) and his crew share a picture from a tree planting location in Sayward on Vancouver Island from when they were filming for ‘One Million Trees’ last year. Photo courtesy, Everett Bumstead.
The tree-planting life on Vancouver Island featured in new documentary

Everett Bumstead brings forth the technicalities, psychology and politics of the tree planting industry in his movie

JaHyung Lee, “Canada’s oldest senior” at 110 years old, received his first dose of the COVID-19 vaccine on Thursday, Jan. 14, 2021. He lives at Amenida Seniors Community in Newton. (Submitted photo: Amenida Seniors Community)

Most Read