I'm an Epidemiologist. Every Day I Wonder what Else the Public Health Illuminati Isn't Hiding from Us.

Funny how they don't test vaccines on lizards.

Greetings, Dave’s babies. I’m Brooke Aksnes, immunization-specialized epidemiologist standing in for Dave this week while he swoons over his (brand-new!!) actual baby. Don’t worry, bud—you’ll figure out how breastfeeding works soon! We’re all rooting for you.

While Dave and I have known each other for decades, I was super flattered when he asked me to Jackal on COVID-19 vaccines for him this week. Of course, I am steadfastly ignoring the possibility I was his plan H. Either way, here we are.

Before we begin, I should make clear that the views expressed here are my own. They should in no way be understood as representative of the views of my employer or as an official communication. All information cited below is publicly available, and I wrote this newsletter free-of-charge.

Let me tell you--at a time when the nation is some warped partisan case study on the Dunning-Kruger effect, it’s tough to be an immunization-specialized epidemiologist. I have colleagues with agency-identifying parking permits on their cars that have been accosted in the street, and people I barely know have gone out of their way to “own” me with misinformation. I’ve even had to excuse myself from family dinner after being challenged on data, public health agencies and national/global responses as if a) I invented science and b) I’m personally responsible for unpopular high-profile decisions.1

Sudden hostility aside, there are COVID vaccine skeptics who ask me questions in good faith. Most frequently, they want to know why mainstream public health institutions (AKA the Public Health Illuminati) insist that COVID-19 vaccines are highly effective despite the higher-than-expected breakthrough cases (i.e., people who are vaccinated against COVID-19 catch it anyway) and why research on the actual effectiveness of the vaccines is being hidden. I’d like to talk a bit about that below. As brevity is the soul of getting you to read to the end of this, I won’t be getting into vaccine safety today. Dave has actually lined up an anti-vaxxer born again to write on this a few Jackals from now.

COVID-19 vaccines: clinical trials are not real life

Note: COVID-19 vaccine efficacy and effectiveness can be measured in a number of ways. This includes protection against catching COVID-19 and protection against hospitalization or death from the virus. I am specifically referring to protection against catching the virus here.

When clinical trials results for Pfizer and Moderna came out, the public health world was over the moon. That’s because vaccines protecting against catching a virus at over 90% is more than we could have hoped for (reported protection was 95% Pfizer and 94.1% Moderna). At over 60% efficacy, the results for AstraZeneca (62.1%) and Johnson and Johnson (66.9%) were also pretty damn good. (Consider that the annual flu shot, which averted an estimated 7.5 million influenza cases during the 2019-2020 flu season, is usually around 40-60% effective).2

While the vaccines’ clinical results were justifiably met with popping of virtual champagne, public skepticism ensued when rates of breakthrough cases did not match clinical expectations. Here’s the thing: clinical trials are not--and should not be expected to be--real life. An important example here is oral birth control pills (trigger warning for those averse to reproduction): While some clinical trials show efficacy of oral contraceptives above 99%, effectiveness in real life has been shown to be around 92%. This is a normal discrepancy; “perfect use” of a medical intervention is rarely seen outside highly controlled trials. COVID-19 vaccines are not always perfectly administered, and clinical trials cannot test for rapidly evolving conditions (i.e., viral variants, varying use of masks and community exposure, quality of healthcare).

Okay, so why was it hidden from the public that clinical trial data was not going to reflect the final vaccine effectiveness? The short and long answer: it wasn’t, and it isn’t.

Mainstream sources of public health information are not “concealing” that gaps exist between clinical and real-life efficacy of COVID vaccines. In fact, if you Google “COVID-19 vaccine effectiveness research”, the first result will send you to a CDC website that says:

“After FDA approves a vaccine or authorizes a vaccine for emergency use, it continues to be studied to determine how well it works under real-world conditions. CDC and other federal partners will be assessing COVID-19 vaccine effectiveness under real-world conditions. Such evaluations will help us understand if vaccines are performing as expected outside the more controlled setting of a clinical trial.” [My emphasis]

Or take the World Health Organization’s (WHO) COVID-focused webpage on vaccine efficacy, effectiveness and protectionwhich more simply says:

“All COVID-19 vaccines approved by WHO for emergency use listing have been through randomized clinical trials to test their quality, safety and efficacy. To be approved, vaccines are required to have a high efficacy rate of 50% or above. After approval, they continue to be monitored for ongoing safety and effectiveness.” [My emphasis]

But where are those OTHER data buried?

Cool. Public Health Kanye West hasn’t been strongarming anyone into hiding fundamental epidemiological principles from the public. Got it. But then why is no one telling us how effective the vaccines really are?! Please find below some effectiveness data points from recent real-world studies on Pfizer and Moderna COVID vaccines3 that might provide answers:4

  • Pilishvili and colleagues found that healthcare personnel vaccinated with two doses of Moderna were protected at 82%, and those vaccinated with two doses of Pfizer were protected at 94% (Source)

  • Tenforde and colleagues determined overall vaccine efficacy after two doses of either Pfizer or Moderna to be 94% in fully vaccinated adults; efficacy for adults 65 years of age and above was 64% (Source)

  • Thompson and colleagues found efficacy of either Pfizer or Moderna to be 90% after two doses and 80% after one dose (Source)

  • Britton and colleagues observed a 63% level of protection among those living in skilled nursing facilities (i.e., nursing homes) after receiving one dose of Pfizer.(Source)

As one would expect, most of the above stats showed the Pfizer and Moderna vaccines to be less effective under their study designs than what was observed in clinical trials. We obviously have the evidence, so where are the mainstream public health institutions burying it?!? Suspiciously enough, every study cited above can be found about two clicks into the CDC’s website and was conducted with or by CDC researchers. It’s almost like they want to be transparent with the public or something… Weird.

While the numbers above are less than those seen in clinical trials, the studies consistently show that the vaccines are highly effective.5 And if you’ve noticed the variations in results, it’s worth mentioning that those variations are not caused by bad science or ominous meddling from The Guys on CNN™. Different study designs and populations (age, profession, setting) as well as the practical inability to control for factors like viral exposure, logistical capacities, time since vaccination, changing contexts and viral variants produce expected differences in study outcomes.

Bottom line: publicly available data clearly tell us that vaccines are a strong weapon in our arsenal against the COVID-19 pandemic, and mainstream public health institutions have built navigable, transparent resources to share the scientific nuances of this fact. The good, the bad and the informative are a 30-second Google search away. As far as “burying” and “evidence” are concerned, it may be time to instead sound the alarm over those who have buried themselves under conspiratorial “evidence” lacking in effort and context. There’s only so much oxygen left under there.

Smooth transition: below are your “should reads” for the week. None of them are informative, but all of them are fun.

The Black Hole by hidden gem Joshua Chaplinsky. If you need to be gut-punched in your feelings this week, this short story about a father whose children’s lives time-warp by him from outside the bar, this is for you.

Lyrics to Bo Burnham’s “Comedy”, because it takes a special kind of white guy to introspectively roast an entire Twitter sub-population. (“Should listen” version here.)

An uplifting story on the Greater One-Horned Rhino, whose population is now 37 times greater than it was in the early 1900s.

That’s all from me, friends. Rest assured, Dave has no obligation to invite me back. My best wishes to the new family of four (Doris counts!), and thanks for reading. Mask up!


- My mom said I wasn’t allowed to say this. BOO. YAH.


- In the spirit of proving a point, I have only taken research directly available from the CDC’s COVID-19 Vaccine Effectiveness Research page. At the time of writing, there were no results linked for Johnson and Johnson or AstraZeneca vaccines.


- Note: Efficacy from two doses of Pfizer could not be determined due to statistical limitations of the data.


- Remember, a decent year for the flu shot, which averted an estimated 7.5 million influenza cases during the 2019-2020 flu season, is around 60% efficacy.

A guest post by
Brooke is an immunization-specialized epidemiologist working in global health. She thinks your attempt at a witty bio is stupid and contrived. Views are her own.
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