Inspired by a conversation this weekend with someone ranting about “stupid anti-vaxxers”, the remarkably poor Canadian media coverage of the COVID-19 situation needs to be addressed. For context, the conversation was about vaccine passports recently proposed by the Quebec government. This person seemed remarkably mis/un-informed not only about the published research and data on COVID-19, but also the flu vaccine and pretty much any history of previous public health crises. Thanks, CBC.
To briefly touch on those last two points first:
No, the flu vaccine is neither highly effective nor low-risk. Officially published CDC data indicate an adjusted seasonal flu vaccine effectiveness rate averaging 40 percent over the past decade — ironically, the referenced section in the CDC report is titled ‘Flu Vaccines Work’. CDC-funded research published in the journal Vaccine found a 7.7 times greater risk of spontaneous abortion among pregnant seasonal flu vaccine recipients. In response, follow-up CDC-funded research also published in Vaccine omitted the years of data used in the original research and found no such risk. This episode prompted a British Medical Journal (BMJ) article critical of the CDC, media coverage of the episode, and flu vaccine effectiveness and risk reporting in general (‘Official doubletalk hides serious problems with flu shot safety and effectiveness’).
No, the current COVID-19 situation is nowhere near as dire as the 1918-1920 influenza pandemic, aka ‘Spanish Flu’. An estimated 500 million were infected and 50 million died during the Spanish Flu. With nearly three times the number of cases and ten times the number of deaths among a human population less than a quarter of what it is today, the Spanish Flu was orders of magnitude worse than COVID-19 has been to date.
So what if people are confused about these details; what do they have to do with what is going on right now? A great deal, actually.
For starters, the public appears to be just as misinformed about COVID-19 vaccines as it is about seasonal flu vaccines. For context, the person who made the referenced “stupid anti-vaxxers” comment – call him Raphael – also said he “felt like Superman” after getting his first COVID-19 vaccine dose, an Oxford-AstraZeneca injection.
It is worth going through a quick timeline of reporting on this specific vaccine to illustrate the problem.
On February 26, 2021, a news item from the CBC titled ‘Health Canada approves AstraZeneca’s COVID-19 vaccine: Canada’s regulator estimates vaccine’s efficacy at 62.1 per cent‘. Notably, a section of the article titled ‘Still better than the flu shot’ actually overstates the effectiveness of the flu vaccine at 54 to 64 per cent without citing any source other than interview comments from Dr. Supriya Sharma of Health Canada. That same section quotes Dr. Sharma saying, “I think Canada is hungry for vaccines. We’re putting more on the buffet table to be used.” Corny and completely uninformative, that quote sums up the lack of effort and complete absence of critical reporting. The main points the article emphasised were “the shot has 100 per cent efficacy in preventing the severe outcomes of COVID-19 — including serious illness, hospitalizations and death” and “overall, there are no important safety concerns, and the vaccine was well tolerated by participants”.
On May 28, 2021, a follow-up news item from the CBC titled “Future of AstraZeneca COVID-19 vaccine in question in Canada over blood clots, supply issues: Risk of blood clots tied to AstraZeneca shot now estimated at 1 in 55,000 in Canada”. Apparently, the AstraZeneca vaccine was no longer welcome on the ‘buffet table’. This news item did provide readers one piece of useful information that was previously omitted from the CBC reporting, a quote from Dr. Andrew Morris, an infectious diseases specialist at the University of Toronto: “For the people who are in their 30s and 40s, it just doesn’t make sense. They’re at really low risk of dying from COVID and they’re assuming a risk of dying from this (vaccine).”
For those following the chronology, the CBC quickly went from reporting “overall, there are no important safety concerns, and the vaccine was well tolerated by participants” to “risk of blood clots tied to AstraZeneca shot now estimated at 1 in 55,000 in Canada”, which itself is misleading and understates the risk. That estimate did not refer to blood clots in general, but vaccine-induced immune thrombotic thrombocytopenia (VITT) in particular, far more likely to lead to permanent brain damage or death.
Some basic critical reporting would have cautioned the public against making any broad assumptions about either vaccine efficacy or safety based on short-term, limited drug trials. A cursory reading of an AstraZeneca press release the CBC actually cited in its reporting shows the safety and efficacy data was based on 21,583 trial participants who received the vaccine. A link in the press release to a summary of the AstraZeneca vaccine Phase III clinical trial information indicates efficacy was based on 15 day follow-up and safety was based on 28 day follow-up post-vaccination. Given the number of vaccine recipients and the short follow-up duration, it would have been impossible for the trial to capture risk of VITT, among other seious or potentially life-threatening risks.
That data, which would certainly be collected as part of the Phase III AstraZeneca vaccine trial, does not appear to have been published. The National Advisory Committee on Immunization (NACI) Recommendations on the use of COVID-19 vaccines notes for AstraZeneca: “Results from an ongoing Phase 3 trial in the United States (US) were not available at time of writing.” (last updated 2021/07/02).
However, the same NACI report provides some sparse, preliminary data on the Pfizer-BioNTech and Moderna Phase III trials.
Here is where understanding the difference between relative and absolute risk is important. Relative risk reduction (RRR) indicates the reduction in infection risk between the vaccinated and placebo groups relative to the total number infected in both groups. Absolute risk reduction (ARR) indicates the reduction in infection risk between the vaccinated and placebo groups relative to the total number of individuals in each group. In other words, RRR focuses on those who were infected, whereas ARR looks at the total population in assessing risk of infection.
Now,take Table 7, summary for Pfizer-BioNTech, from the NACI reccomendations report, for example. While the NACI report does not provide the ARR, it is easy enough to calculate given the number of infected in the vaccinated and placebo groups and the total number of participants in each group. For dose 1, the VEARR=(82/21,686)-(39/21,669)=0.20 per cent. For dose 2, the VEARR=(169/20,172)-(9/19,965)=0.79 per cent. The RRR, which the NACI report does provide, cancels out the impact on the total number of trial participants. The 1 dose VERRR=1-[(39/21,669)/(82/21,686]=52.4 per cent. The 2 dose VERRR=1-[(9/19,965)]/(169/20,172)]=94.6 per cent. The NACI report highlights the RRR figures, depite the fact they are less meaningful in terms of reducing overall COVID-19 impact than the ARR.
Notably, the NACI report does not give a detailed breakdown of adverse events. However, it does note the vaccine group experienced 1.1 per cent incidence of “serious adverse events” and 0.1 per cent experienced “life-threatening adverse events” — from a vaccine that provided less than 1 per cent ARR in preliminary Phase III trial results.
Of course the limited period of the preliminary trial results – just 14-day follow-up after each dose – is insufficient to determine longer-term effects. It is likely vaccine efficacy will decline as vaccine risk rises over time, especially for a new vaccine using novel mRNA technology being widely deployed for the first time.
Such questions about vaccine efficacy and risk did not escape the attention of the BMJ, whose editors were skeptical about the remarkably high efficacy rates and low risks reported by the Moderna and Pfizer COVID-19 vaccine trials.
On November 17, 2020, a BMJ news item touted 95 per cent efficacy for the Moderna and Pfizer vaccines.
A November 30, 2020 letter to the editor of the BMJ from deputy editor-in-chief of the British Journal of Pharmacy (BJP) Hamid Merchant outlined 7 reasons vaccine efficacy and safety, particularly of the novel mRNA vaccines developed by Moderna and Pfizer, to-date were likely widely overstated. It concluded with the following statement:
“In light of the above, the actual efficacy of the vaccine is likely to be much lower. This publicity, no doubt, has given the world great hope but can be disappointing to the public when the long-term efficacy was not as good as claimed in the interim assessment. Albeit not a surprise to many clinicians and scientists, the public may react badly. This may also fuel anti-vaccine thoughts and is not in the greater interest of public safety and may jeopardise their trust in science and medicine. Moreover, this is going to be the first mRNA-based vaccine being developed for the mass public use and a longer-term safety and efficacy assessment is inevitable. The mass publicity and celebration of the interim results, therefore, was a very bad idea and likely to have adverse implications.”
Dr. Hamid Merchant, Deputy Editor-in-Chief, British Journal of Pharmacy
A November 26, 2020 BMJ opinion column by associate editor Peter Doshi followed up on Dr. Hamid’s skepticism by outlining several specific concerns:
“First, a relative risk reduction is being reported, not absolute risk reduction, which appears to be less than 1%. Second, these results refer to the trials’ primary endpoint of covid-19 of essentially any severity, and importantly not the vaccine’s ability to save lives, nor the ability to prevent infection, nor the efficacy in important subgroups (e.g. frail elderly). Those still remain unknown. Third, these results reflect a time point relatively soon after vaccination, and we know nothing about vaccine performance at 3, 6, or 12 months, so cannot compare these efficacy numbers against other vaccines like influenza vaccines (which are judged over a season). Fourth, children, adolescents, and immunocompromised individuals were largely excluded from the trials, so we still lack any data on these important populations.”
Dr. Peter Doshi, Associate Editor, British Medical Journal
Subsequent to publication of some of the Pfizer Phase III trial results and summary data, a January 4, 2021 follow-up BMJ opinion column by Dr. Doshi questioned the trasparency and integrity of the clinical trials. Specifically, it pointed to many times more “suspected covid-19” cases that were never PCR test confirmed and excluded as cases that were PCR test confirmed and included in the Pfizer study: “With 20 times more suspected than confirmed cases, this category of disease cannot be ignored simply because there was no positive PCR test result.” It proceeded to point out that, depending on how those cases were to be allocated, the RRR could be as low as 19 per cent, well below the 50 per cent threshold required for vaccine approval. It also points to a disproportionate number of exclusions from the vaccinated group (311) relative to the placebo group (60) among numerous other apparent irregularities in the Pfizer study. Dr. Doshi also highlights that these trials are not expected to conclude until “sometime in mid-to-late 2022”, after which the trial data may or may not be released.
This skeptcism was not just limited to the BMJ. On February 26, 2021, Medicina published a commentary titled ‘Outcome Reporting Bias in COVID-19 mRNA Vaccine Clinical Trials’. On April 20, 2021, The Lancet published a commentary titled ‘COVID-19 vaccine efficacy and effectiveness—the elephant (not) in the room‘.
None of this information is terribly complex to communicate nor understand. By this point, the vast majority of the CBC audience is familiar with the terminology used and can appreciate the concern – or ‘skepticism’ – raised by medical publications such as the BMJ, The Lancet and Medicina regarding vaccine efficacy and safety. Instead of informing the public, the CBC decided to write puff pieces about putting more vaccines on the ‘buffet table’. It seems the CBC is incapable of learning even from its own very recent experience where it had to dramatically change its positive initial reporting on AstraZeneca vaccine efficacy and safety.
The public health consequence of such poor public disclosure and lack of critical reporting is people like Raphael thinking they are Superman because they have been vaccinated. Putting on a cape and jumping out of a window thinking you can fly is a terrible way to go.
Provincial governments, such as Quebec and Manitoba, with their proposed vaccine passports, will effectively be encouraging such recklessness, giving those who have been vaccinated a false sense of security about vaccines with questionable ongoing clinical trials. Worse yet, such policies appear intended to coerce those with reasonable concerns to take a risk that may not be otherwise warranted given their personal risk profile.
Those who have already received a first dose, particularly those receiving AstraZeneca and subsequently being offered a Moderna or Pfizer second dose, should carefully consider their options. There has been no long-term or even short-term clinical trials on either the efficacy or safety of such a ‘mix and match’ approach. Preliminary data from a very small UK study (Com-COV) show a remarkable increase in adverse events among those receiving different vaccines for their first and second doses; 316 adverse events from 178 participants up to 28 days following vaccination — and that is from a total of just 463 vaccinated participants in the study.
Those who have been fully vaccinated should continue to take precautions, such as masking and appropriate physical distancing, since little is known about the risks of either contracting or spreading SARS-CoV-2, the virus that causes COVID-19, even after full vaccination. As noted herein and in the referenced medical journals, there are concerns with the preliminary data on both the benefits and risks of the various COVID-19 vaccines in ongoing clinical trials. The relative efficacy rates are likely to continue to decline as the risks are likely to continue to rise over time. The absolute efficacy rates are negligible, actually lower than the risk of developing serious side-effects from vaccination.
Those who have not yet been vaccinated should heed the only useful piece of advice offered in the CBC reporting, specifically Dr. Morris’ advice to assess their personal situation and risk. Several provincial governments have published data on COVID-19 cases, hospitalisations and deaths.
In Quebec, for example, those age 40-49 comprised just 0.4 percent of deaths, 6.0 per cent of total hospitalisations and 8.4 per cent of ICU admissions. With data published to date and given the province’s population, a Quebecer in their 40s would have had a 1 in 171,000 chance of dying and 1 in 24,000 chance of ending up in ICU since the outset of the COVID-19 situation in the province. Those in the referenced age group can then use those figures and weigh their chances of having serious or life-threatening side-effects from the vaccine against their chances of having severe or life-threatening symptoms as a result of contracting SARS-CoV-2. The cost-benefit analysis changes dramatically with age. The Quebec data shows more than 90 per cent of deaths since the outset of COVID-19 were among those age 70 and up. Risk also increases with certain pre-existing conditions, although no detailed information or data is provided in the Quebec report.
The ‘vaccine hesitant’ or ‘vaccine skeptical’ are quite justified in this instance. They should not be coerced into making potentially life-altering decisions about their health based on incomplete and questionable vaccine trial data. Given their concerns are not only well-founded, but shared by editors of some of the top medical research journals in the world, give the ‘anti-vaxxer’ thing a rest already.