A vial of AstraZeneca vaccine is seen at a mass COVID-19 vaccination clinic in Calgary, Alta., Thursday, April 22, 2021. Dr. Ben Chan remembers hearing the preliminary reports back in March of blood clots appearing in a handful of European recipients of the Oxford-AstraZeneca COVID-19 vaccine. THE CANADIAN PRESS/Jeff McIntosh

A vial of AstraZeneca vaccine is seen at a mass COVID-19 vaccination clinic in Calgary, Alta., Thursday, April 22, 2021. Dr. Ben Chan remembers hearing the preliminary reports back in March of blood clots appearing in a handful of European recipients of the Oxford-AstraZeneca COVID-19 vaccine. THE CANADIAN PRESS/Jeff McIntosh

Science on COVID, VITT constantly changing: A look at how doctors keep up

While VITT can represent challenges as a novel disorder, blood clots themselves are not new

Dr. Ben Chan remembers hearing the preliminary reports back in March of blood clots appearing in a handful of European recipients of the Oxford-AstraZeneca COVID-19 vaccine.

The global health expert with the University of Toronto followed the developments closely over ensuing weeks as researchers went from examining what was going on to determining how to diagnose and treat it.

The disorder, characterized by low platelet counts, is now called vaccine-induced thrombotic thrombocytopenia, or VITT. It continues to be an exceedingly rare side effect seen in a small number of recipients of adenovirus vector vaccines.

The science surrounding VITT continues to evolve quickly, and medical professionals have found themselves bombarded with developments, including changing guidance on patient care.

“In my 30-plus years working in the medical system, I don’t think I’ve ever seen such a short time period between discovering something, figuring out how to manage it, and getting the information out into the field,” says Chan.

When a time-sensitive issue like VITT arises, there are multiple ways urgent updates make their way to physicians, nurses and ER staff, note several experts who say the public can feel confident the health system has kept pace with new discoveries.

Dr. Michael Hill, a neuroscience professor at the University of Calgary, says communication varies from province to province and involves multiple avenues, but the goal is to reach hospital staff “very quickly.”

“When you try to get a message out to a huge number of people, you have to do it in a multifaceted way,” says Hill, also director of the stroke unit for the Calgary Stroke Program.

“You can’t just depend on one communication channel.”

He notes a bulletin this week from Alberta Health Services reached approximately 100,000 emergency room doctors, nurses, internists and neurologists via a system-wide email before being posted around hospitals in physical form.

In Ontario, the province’s Science Table recently shared updated guidance that included an extension of the time frame of VITT symptom onset to 4-to-28 days, a change from 4-to-20 days. Chan, who helped author the document, says the update was emailed to various groups.

Meanwhile, over at the Unity Health Network in Toronto, hospital staff use various platforms including email, meetings and WhatsApp group chats to ensure they’re up to date on the latest science, says Dr. Erin O’Connor, deputy chief of the network’s emergency department.

She says social media has also played a role as medical professionals pay closer attention than ever to what global colleagues tweet about their own research or other notable studies.

“It’s fascinating how information has been disseminated in the time of COVID,” says O’Connor. “Everything is changing so rapidly. I mean, some protocols have changed every couple of weeks as we learn more.”

Just this past Friday, an article published in the Canadian Medical Association Journal dismissed initial notions VITT affects mostly younger women and called on doctors and staff to be alert for anyone with possible symptoms.

The article highlighted the case of a 63-year-old man who developed signs 20 days after receiving his AstraZeneca vaccine.

As of Thursday, there were 18 confirmed cases of VITT in Canada — out of more than two million doses of AstraZeneca administered — with 10 more under review. Three Canadians have died.

Most provinces announced last week they’ll no longer offer AstraZeneca as a first-dose option.

Provinces have also issued guidance on symptoms to watch for — including persistent, severe headache; blurred vision; chest, back or abdominal pain; swelling in a limb and multiple bruises — along with information on how to diagnosis and treat the disorder.

At the federal level, Health Canada issues information on vaccine safety concerns, and along with the Public Health Agency of Canada, has put together “a network of clotting (and) hematology specialists across the country,” available for consultations, says chief medical adviser Dr. Supriya Sharma.

Sharma adds it’s up to provincial and territorial governments to inform front-line health professionals who could see potential VITT cases.

Keeping up with an ever-evolving scientific landscape is part of a doctor’s job.

Chan notes Canadian doctors must earn continuing education credits to remain certified with their specialty societies, with each credit roughly equivalent to an hour of lectures, reading or group study. The minimum is 50 credits per year for family doctors and 80 for specialists.

While VITT can represent challenges as a novel disorder, blood clots themselves are not new.

O’Connor says triage nurses — a patient’s first point of contact in an emergency room — have been trained to spot potential clot symptoms long before VITT emerged.

Hill says the difference now is they’ll ask patients whether they’ve received the AstraZeneca vaccine when presenting with possible VITT signs.

Concerns arose last week when a woman with VITT symptoms was reportedly turned away from an emergency room in Edmonton. The woman went to another hospital, where a CT scan revealed a blood clot, and she died shortly after.

Chan, who didn’t know the specific context of the woman’s case, says human error does sometimes happen in medicine. But, he adds the public should feel confident health professionals know what to look for.

“It’s important that patients who have symptoms like severe headache or bleeding after vaccination seek care immediately and ask that VITT be ruled out,” he says.

— With files from Mia Rabson in Ottawa

Melissa Couto Zuber, The Canadian Press

Coronavirusvaccines

Just Posted

Students at Creston Valley Secondary School put together an art installation of a replica residential school room. (Photo by Kelsey Yates)
Creston students create art installation of residential school room

The replica was decorated with a small bed, school uniform, and notes written with pleas for help

A tent housing a mobile vaccination clinic. (Interior Health/Contributed)
Second dose vaccinations accelerating throughout region: Interior Health

To date, more than 675,000 doses have been administered throughout the region

1914
It happened this week in 1914

June 13 - 19: Compiled by Dave Humphrey from the archived newspapers… Continue reading

Prince Charles Secondary School
School District 8 votes in favour of name change for Secondary School in Creston

In an act of reconciliation, a new name will be chosen for Prince Charles Secondary School

Kootenay-Columbia MP Rob Morrison. Photo courtesy Conservative Party of Canada.
MP Morrison appointed to parliamentary national security committee

Kootenay-Columbia parliamentarian one of five candidates appointed to national security committee

People line up to get their COVID-19 vaccine at a vaccination centre, Thursday, June 10, 2021 in Montreal. THE CANADIAN PRESS/Ryan Remiorz
Vaccines, low COVID case counts increase Father’s Day hope, but risk is still there

Expert says people will have to do their own risk calculus before popping in on Papa

FILE – A science class at L.A. Matheson Secondary in Surrey, B.C. on March 12, 2021. (Lauren Collins/Surrey Now Leader)
Teachers’ union wants more COVID transmission data as B.C. prepares for back-to-school

BCTF says that details will be important as province works on plan for September

Provincial health officer Dr. Bonnie Henry outlines B.C.’s COVID-19 restart plan, May 25, 2021, including larger gatherings and a possible easing of mandatory masks on July 1. (B.C. government photo)
B.C. records 120 new COVID-19 cases, second vaccines accelerating

Lower Pfizer deliveries for early July, Moderna shipments up

A Heffley Creek peacock caught not one - but two - lifts on a logging truck this month. (Photo submitted)
Heffley Creek-area peacock hops logging trucks in search of love

Peacock hitched two lifts in the past month

The Calgary skyline is seen on Friday, Sept. 15, 2017. THE CANADIAN PRESS/Jeff McIntosh
2 deaths from COVID-19 Delta variant in Alberta, 1 patient was fully immunized

Kerry Williamson with Alberta Health Services says the patients likely acquired the virus in the hospital

The first suspension bridge is the tallest in Canada, with a second suspension bridge just below it. The two are connected by a trail that’s just over 1 km. (Claire Palmer photo)
PHOTOS: The highest suspension bridges in Canada just opened in B.C.

The Skybridge in Golden allows visitors to take in views standing at 130 and 80 metres

BC Green Party leader and Cowichan Valley MLA Sonia Furstenau introduced a petition to the provincial legislature on Thursday calling for the end of old-growth logging in the province. (File photo)
BC Green leader Furstenau introduces old-growth logging petition

Party calls for the end of old-growth logging as protests in Fairy Creek continue

B.C. Premier John Horgan leaves his office for a news conference in the legislature rose garden, June 3, 2020. (B.C. government photo)
B.C. premier roasted for office budget, taxing COVID-19 benefits

Youth addiction law that triggered election hasn’t appeared

A vial containing the Moderna COVID-19 vaccine is shown at a vaccination site in Marcq en Baroeul, outside Lille, northern France, Saturday, March 20, 2021. THE CANADIAN PRESS/AP/Michel Spingler
mRNA vaccines ‘preferred’ for all Canadians, including as 2nd dose after AstraZeneca: NACI

New recommendations prioritizes Pfizer, Moderna in almost all cases

Most Read