A document circulating on social media and elsewhere is being cited as a smoking gun to suggest Pfizer knew its COVID-19 vaccine causes more "adverse events" than previously stated, a claim some experts say requires a more nuanced look.
Released by the U.S. Food and Drug Administration as part of a recent U.S. court order, the one-year-old, 38-page report of post-marketing data from Pfizer includes an appendix listing hundreds of reported adverse events from its COVID-19 vaccine, all of which are defined as being of "special interest."
Whether the data is being, or can be, accurately interpreted is a point some experts are flagging as an issue with the document, particularly given the amount of real-world data gathered since then.
Experts say not every adverse event cited in the report can be chalked up to the vaccine, while others are consistent with the vaccine's known side-effects.
CTVNews.ca spoke to two infectious disease specialists about the report to better understand what the data does, and does not, show.
The document itself is an accumulation of post-authorization adverse event reports from Dec. 1, 2020, through to February 2021, taken from the U.S. and other countries, of which there were 42,086 cases in total.
An adverse event is defined as "any untoward medical occurrence that follows immunization," including an unfavourable or unintended sign such as a skin rash, an abnormal lab finding, symptom or disease.
Dr. Dale Kalina, an infectious disease doctor at Joseph Brant Hospital in Burlington, Ont., told CTVNews.ca in a Zoom interview on Tuesday that Pfizer is required to report any adverse events.
However, just because someone reports an adverse event doesn't mean it was caused by the vaccine itself.
As the document states, adverse event reports do not necessarily mean they were caused by the drug in question, but could be due to an underlying disease or other factor.
During the Pfizer vaccine trial for those between five and 11-years-old, Kalina says one participant swallowed a penny, which was reported as an adverse event.
"And I think we can all agree that swallowing a penny isn't related to the vaccine itself," he said.
"But of course, it highlights the fact that it needs to be reported and that's what we're seeing, and that's the type of data that we're getting."
During Moderna's vaccine trials, a 72-year-old participant with arrhythmia, who died after being struck by lightning 28 days post-vaccination, was reported as experiencing a severe adverse event.
Dr. Martha Fulford, an associate professor of medicine at McMaster University, says it's also unclear in the list whether the adverse events were actually linked to the vaccine or if it was by coincidence.
"I look at this document and I think I sort of come away thinking it's a little uninterpretable to me," she told CTVNews.ca in a phone interview on Wednesday.
One of the events listed is hantavirus pulmonary infection, which can occur after coming into contact with rodent urine, droppings or saliva.
"Product availability issue" also is another adverse event on the list.
"Some of that stuff strikes me as highly improbable as doing anything with the vaccine," Fulford said.
Reporting of adverse events, generally, is underreported, Fulford says, which is something the Pfizer document notes, as well.
But she says it's unclear how many actual cases of each adverse event were reported or if they appeared at higher rates than what you would see by random chance in the general population.
"The key is whether or not there's a link and so people reporting something that's happened, we would need to look at what the overall reported rates would be across a population in a normal period of time," Fulford said.
Both Kalina and Fulford pointed to the lack of a denominator in the document, or in this case how many people received the vaccine at that point in time.
Near the end of February 2021, the United States was vaccinating as many as 1.7 million Americans on average per day, with 63 million Moderna and Pfizer vaccines administered.
Looking at the more common adverse events in the Pfizer document, seen in two per cent of cases or more, all are what one would expect after getting a vaccine and when the immune system is excited, namely sore arm, mild fatigue and headache, Kalina says.
The "heaps" of data produced since then around the world have underscored that, he says.
"But to label it as adverse, I think, is a bit of a misnomer because it is actually exactly what you would expect," he said.
"You're expecting that reaction and although it's adverse, it's not pleasant, it is what you would expect from the medication itself."
Kalina says any suggestion of a cover-up by Pfizer is being made for "nefarious purposes."
"It's a pharmaceutical company, they're here to make money and I recognize that, there's no doubt in my mind about that, but the product works," he said.
While the initial optimism around transmission, for example, has certainly waned as more vaccinated individuals became infected with the Omicron variant, that doesn't take away from the power of the vaccine to prevent serious disease, hospitalization and death, Fulford says.
"I think most of us, myself included, feel very strongly that for vulnerable people who are at risk from COVID, the vaccines have fundamentally changed what we were dealing with," she said.
"We saw a huge difference in hospital admissions and severe disease mortality in people who had been vaccinated, this is unquestioned. The risk-benefit conversation obviously changes very much depending on the baseline risk of the person receiving the vaccine, it's just not an absolute answer."
The Public Health Agency of Canada says that as of Feb. 25, 2022, a total of 40,011 adverse events following immunization have been reported, out of nearly 80.8 million doses administered, for a rate of 0.05 per cent. Most of the adverse effects are classified as non-serious.
At the time the Pfizer report was made, many of those who got the vaccine initially were generally older and potentially vulnerable to COVID-19 infection.
Since then, vaccines have been administered to more, and younger, age groups, providing further evidence to back certain adverse events.
As Fulford says, what needs to be monitored with any medication or vaccine is whether certain signals present at a higher rate than what you would normally see.
This proved to be the case with blood clots and the AstraZeneca vaccine.
Although blood clots can emerge from sitting too long due to travel and certain birth control, their presence after receiving AstraZeneca, while rare, made it distinct, Fulford says.
A similar situation has played out with myocarditis and pericarditis, or inflammation of the heart muscle and lining around the heart respectively.
While also considered rare, people have reported cases after receiving a COVID-19 mRNA vaccine, with higher rates observed following a second dose, among young and adolescent males, and with the Moderna vaccine, the latter possibly due to it being a higher dose than Pfizer.
A report on adverse events from Public Health Ontario shows that rates of myocarditis and pericarditis in males 12-17 and 18-24 after receiving a second dose was 157.9 and 199.4 respectively per million doses, which is roughly two to 13 times higher compared to other age groups.
One recent study also points to the need for individual strategies for vaccinating adolescent boys, due to the elevated risks of myocarditis and pericarditis, and depending on their health and history of COVID-19 infection.
The National Advisory Committee on Immunization recommended in December 2021 that Pfizer be the preferred COVID-19 vaccine over Moderna for those 12 to 29-years-old.
Some studies also have looked into the potential effects of COVID-19 vaccines on women's menstrual cycles.
Ultimately, Fulford says conversations around the risks and benefits of getting the vaccine will vary depending on the individual.
"It's not to say that people should or should not be vaccinated, it's simply acknowledging that yes, we have seen in some people adverse events, and acknowledging that there's an adverse event is not an all or nothing, and we've sort of made it an all or nothing," Fulford said.
"One can be in favour of vaccines while acknowledging this is the risk in this age group of this adverse outcome, and have that risk-benefit conversation."
With files from CTV News
Chart every case of COVID-19 in each province and territory across the country
Track the number of people in Canada and around the world who have received vaccinations
Curious how different countries are faring? Chart and compare the curves using our interactive graphs
Sign up to receive the most important updates in your inbox two times a week
The common-law spouse of the man responsible for the Nova Scotia mass shooting told an inquiry Friday that she lied to police about his illegal weapons and failed to report earlier violent behaviour because she was deeply afraid of him.
The cost of dairy is set to rise again across Canada, but one food policy expert says there may be relief on the horizon if other food prices stabilize before the end of the year.
New Brunswick Premier Blaine Higgs is replacing his health minister and the CEO of the Horizon Health Network after a patient died this week in an emergency department waiting room in Fredericton.
While some Canadians are left axing plans for home improvements and decreasing grocery budgets, others, including those hoping to enter the housing market amid now-falling prices, see the recent interest rate hike as a 'positive' opportunity.
A Vancouver surgeon and businessman has lost his appeal of a landmark court case that threatened the foundations of the Canadian health-care system.
Before Ripudaman Singh Malik was gunned down in Surrey, B.C., on Thursday, a white Honda CRV pulled up to the shooting scene. Homicide investigators say the occupants waited hours for him to arrive.
MPs are launching a full study and will be calling for key ministers and international officials to testify on the federal government's contentious decision to grant a two-year exemption to federal sanctions, allowing a Canadian company to return repaired turbines from a Russia-Germany natural gas pipeline.
A refugee family who has been stuck in a Canadian hotel for nearly 11 months after fleeing from Afghanistan says a temporary house they were being offered to live in was overpriced and a waste of taxpayer dollars.
Parliamentarians on the House of Commons Industry and Technology committee voted on Friday to study the Rogers outage, with at least two meetings scheduled before July 30.
The common-law spouse of the man responsible for the Nova Scotia mass shooting told an inquiry Friday that she lied to police about his illegal weapons and failed to report earlier violent behaviour because she was deeply afraid of him.
Before Ripudaman Singh Malik was gunned down in Surrey, B.C., on Thursday, a white Honda CRV pulled up to the shooting scene. Homicide investigators say the occupants waited hours for him to arrive.
While some Canadians are left axing plans for home improvements and decreasing grocery budgets, others, including those hoping to enter the housing market amid now-falling prices, see the recent interest rate hike as a 'positive' opportunity.
Parliamentarians on the House of Commons Industry and Technology committee voted on Friday to study the Rogers outage, with at least two meetings scheduled before July 30.
A rapidly spreading wildfire near Lytton, B.C., has grown hundreds of hectares and a special air quality statement has been issued for the area.
One person remains unaccounted for after a rooftop parking lot collapsed in East Vancouver Thursday.
A crucial meeting to repair one of the world's most important diplomatic relationships began with a fist bump Friday as Saudi Crown Prince Mohammed bin Salman welcomed U.S. President Joe Biden at a royal palace.
A German court on Friday convicted a military officer who posed as a Syrian asylum-seeker of plotting to attack prominent politicians, sentencing him to 5 1/2 years in prison.
Jayland Walker, the 25-year-old Black man who died last month at the hands of police in Akron, Ohio, was shot dozens of times, with 26 bullets recovered from his body, according to a preliminary autopsy report released Friday.
A man exonerated last November in the 1965 killing of civil rights leader Malcolm X has sued New York City after it admitted to have wrongly branded him a murderer.
A British aid worker detained by pro-Russia separatists in Ukraine has died in captivity, a separatist official and a U.K. charity involved with his case said Friday.
Italy entered into days of political and financial uncertainty Friday as political leaders calculated their options and Premier Mario Draghi weighed his after populist ally the 5-Star Movement sparked a crisis by withholding support on a government-sponsored bill.
Parliamentarians on the House of Commons Industry and Technology committee voted on Friday to study the Rogers outage, with at least two meetings scheduled before July 30.
MPs are launching a full study and will be calling for key ministers and international officials to testify on the federal government's contentious decision to grant a two-year exemption to federal sanctions, allowing a Canadian company to return repaired turbines from a Russia-Germany natural gas pipeline.
A little more than a month after pausing the measure, the Public Health Agency of Canada announced Thursday it will be re-implementing random COVID-19 testing for fully vaccinated air travellers arriving into the country at four major Canadian airports: Vancouver, Calgary, Montreal and Toronto.
No amount of alcohol is healthy if you are younger than 40, mostly due to alcohol-related deaths by auto accidents, injury and homicide, according to a new global study.
A Vancouver surgeon and businessman has lost his appeal of a landmark court case that threatened the foundations of the Canadian health-care system.
New Brunswick Premier Blaine Higgs is replacing his health minister and the CEO of the Horizon Health Network after a patient died this week in an emergency department waiting room in Fredericton.
NASA astronauts will go back to riding Russian rockets under an agreement announced Friday, and Russian cosmonauts will catch lifts to the International Space Station with SpaceX beginning this fall.
Amazon's Ring doorbell unit, which makes videos of the outside of an owner's home, gave footage to law enforcement without the user's consent 11 times so far this year, the company said.
A signal consisting of fast bursts of radio waves in a clear pattern has been detected emanating from deep space — and astronomers believe it could be used to measure the expansion of the universe in the future.
This week, pop culture critic Richard Crouse reviews new movies: 'Where the Crawdads Sing,' 'Mrs. Harris Goes to Paris' and 'Hallelujah: Leonard Cohen, A Journey, A Song.'
Actor Pat John, known for the classic Canadian comedy-drama series "The Beachcombers," has died, according to one of his co-stars.
Julianne Moore has been selected to serve as president of the main competition jury for the Venice International Film Festival this year, festival director Alberto Barbera announced Friday.
The national real estate market's cooling continued with home sales falling again in June, but the Canadian Real Estate Association said the decreases are smaller than those seen in previous months.
Statistics Canada says wholesale sales rose 1.6 per cent in May to $81.1 billion, boosted by higher sales in the food, beverage and tobacco subsector and the machinery, equipment and supplies group.
The cost of dairy is set to rise again across Canada, but one food policy expert says there may be relief on the horizon if other food prices stabilize before the end of the year.
Hasbro is partnering with the New York Times to create 'Wordle: The Party Game,' a new board game the companies say 'delivers classic Wordle gameplay, but now in an all new way.'
Four years after losing his ability to walk, Mike Shoreman is attempting to cross all five Great Lakes on a paddleboard in an effort to raise money for youth mental health.
A popular Vancouver Island community has been named one of the top 50 places in the world to visit by Time magazine.
Almost a year after Canada downed the U.S. in the Tokyo Olympic semifinal, they meet again -- this time with Olympic qualification on the line.
Thirty women who had accused the Houston Texans of turning a blind eye to allegations that Deshaun Watson was sexually assaulting and harassing women during massage sessions have settled their legal claims against the team, their attorney said Friday.
Jim Thorpe has been reinstated as the sole winner of the 1912 Olympic pentathlon and decathlon in Stockholm -- nearly 110 years after being stripped of those gold medals for violations of strict amateurism rules of the time.
Toyota's flagship model in Japan, the Crown, is going on sale around the world for the first time, including in the U.S.
Andrej Karpathy, Tesla's director of artificial intelligence, announced Wednesday he's leaving the company only months before its anticipated release of its long-delayed 'full self-driving' software to 1 million people. Tesla's driver-assist features made significant advances in his tenure, but also have drawn increased scrutiny from regulators over their safety record.
Among the drivers revved up and ready to race this weekend as Toronto’s Honda Indy finally returns is Devlin DeFrancesco, who was born severely premature in the city two decades ago, and is looking to honour the hospital that saved his life.
© 2022 All rights reserved. Use of this Website assumes acceptance of Terms & Conditions and Privacy Policy