Why I Trust the COVID-19 Vaccine

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Hey everybody, it’s time for a COVID vaccine update! I last talked about the vaccine on March 195th, or approximately mid-September using the old Julian calendar. In that video, I talked about how it’s okay to be skeptical of a vaccine if it was rushed through by Trump prior to the election, and how the US has screwed up in the past by rushing vaccines against the warning of doctors and scientists. But ultimately I suggested that we all relax, wait until the vaccine comes out, and see what the experts have to say.

Well, election day came and went without Trump’s promised vaccine, and thank science for that. Like, that would have been the worst possible scenario: Trump on TV telling people he personally developed a vaccine the same way Homer Simpson invented the Flaming Homer by mixing random things he found around the house including the secret ingredient, Krusty Brand Non-narcotic Kough Syrup. And then everyone would try to reach Dr. Fauci for reassurance but he would have died in a tragic speedboating accident the day prior so we’d all just shrug and line up for our shot.

But happily, Trump’s lie about having a vaccine ready by election day turned out to be “arbitrary,” or in other words, a lie. And a month later, things are actually looking really good! I mean, they’re looking good because Trump lost the election, but also because there are two COVID-19 vaccines that are set up to possibly be approved by the FDA this week (for Pfizer’s) and next week (for Moderna’s).

In light of that, I wanted to update my previous video with the news that as of right now, I am very excited about these vaccines and I will absolutely be getting mine as soon as I can. I won’t be first in line, by a long shot — the first vaccines will be going to frontline healthcare workers and others who are most at risk of contracting the virus. Then it will go to essential workers, older people, those with comorbidities, people in prison and without houses, and eventually everyone else. I work from home, and I’m absolutely disgusted by the idea of interacting with other human beings, so I’m happy to keep sheltering in place until the vaccine is available. I’m expecting the vaccine to be available to me by next Spring, since there are so many people in line ahead of me. If the rollout goes well, then we might be able to enjoy a fairly normal summer.

Note that this is still an extremely fast timeline to develop and implement a vaccine. Should that be a concern? No! Here’s a quick overview of why.

First of all, the Moderna vaccine has actually been around since January, before China even admitted that COVID-19 was able to spread from person to person. Scientists were able to whip it up in a weekend, thanks in large part to previous work done in the aftermath of the 2003 SARS pandemic. SARS was also a coronavirus, and through testing researchers learned that the key to stopping a coronavirus is to target the spiky protein. They do this by using messenger RNA (mRNA), which is a newish way to make a vaccine. You probably think of a vaccine as being a weak or dead version of the virus that trains your body to attack the virus without giving you the full whammy of the disease. That’s not what happens with mRNA — instead, the mRNA just tells your cells to look out for that little spike on the coronavirus. Your body then makes the antibodies without ever actually seeing the whole virus. The mRNA never interacts with any cell nuclei, which means it doesn’t even get close to your DNA. You can think of it like a set of instructions that come with your Ikea desk. Once the desk is built, you can throw the instructions away and you keep the desk.

Scientists have known this type of vaccine is more or less safe. It’s certainly safer than catching COVID-19, and there’s not likely to be any insane side effects. What they don’t know for sure, and what a lot of the trials have been about, is figuring out how effective it is. And what they won’t know until months or years down the line is how long it remains effective. Your cells built the Ikea desk, but how long is that desk going to last? Is it made of real wood or particleboard? Your cells might need to get those instructions back at some point to build another one.

So safety? Check. Both vaccines up for approval in the US are mRNA vaccines, and are definitely safe. And efficacy? Well that’s also looking good. The Moderna vaccine was found to be 95% effective, and if you’re curious about what that means exactly you should check out this easy-to-read post by Mary Brock, Skepchick’s resident antibody expert. The short answer is that it means that 95 people in the Moderna trial got COVID-19, of whom only 5 had received the vaccine. 90 is 94.7% of 95, so that’s the efficacy rate.

And 95% is a FANTASTIC efficacy rate. The annual influenza vaccine, which could save thousands of lives each year if everyone got it, is only about 50% effective each year. 95% is more on track with the MMR vaccine, which after two doses is 97% effective against measles.

As I say, we don’t know how long immunity will last with these vaccines. But we do know that if everyone gets vaccinated, we can get back to normal life. Unfortunately, we already know that not everyone will get vaccinated. Fearmongers have kept people from getting the extremely safe and effective MMR vaccine. Fox News has prevented people from wearing masks and staying home. Just because something is safe and almost guaranteed to work doesn’t mean Americans will do it, thanks to our hyper-politicization of even the most obvious facts. But despite that, I urge you to please do your part, because it does help. Stay home, wear a mask if you have to go out, and when the vaccine becomes available to you, get it. Not everyone is doing the right thing, but the more people who DO do the right thing, the fewer people die. Here in the San Francisco Bay Area, our sheltering in place has had a real, noticeable impact on the health of our residents. As the chair of UCSF’s Department of Medicine points out on Twitter, “if the U.S. had SF’s per capita mortality rate, the nation would have had ~60,000 deaths, not 276,000.” That’s 216,000 people who would still be alive today.

So yes, herd immunity would be great! But even if we can’t reach that, we can still protect the people we love. Keep it up.

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

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  1. I take issue with your maths. Or more precisely your definition of efficacy rate.

    “95 people in the Moderna trial got COVID-19, of whom only 5 had received the vaccine. 90 is 94.7% of 95, so that’s the efficacy rate”

    90 is in fact 94.7% of 95, but this is not the efficacy rate. If 47 instead of 5 of the 95 contracting COVID-19 were vaccinated, then by the above calculations the vaccine efficacy rate would be 48/95, or 50.5% efficacy rate. Hmmmm

    The CDC efficacy/effectiveness calculation is:

    (risk of unvaccinated group – risk among vaccinated group)/ risk among unvaccinated group

    Where risk is the percent contracting the disease in each of the two groups (vaccinated and unvaccinated).


    A devoted follower of your illuminations

    1. Err, sample size = s (actual number doesn’t matter because it cancels out.) S/2 were vaccinated and s/2 got the placebo.

      Risk = R(g) is cases in group = n/s/2, where n = 5 for vaccinated and 90 for unvaccinated. R(u)=90/s/2, R(v)=5/s/2.
      (r(u) – r(v))/r(u) = efficacy = (90/s/2 – 5/s/2)/(90/s/2). Multiply by (s/2)/(s/2) to cancel, results in (90-5)/90 = 85/90=94.44% efficacy, which is pretty darn close to 95%. (By your formula, it should be 85/90, not 90/85, so Rebecca is off by about .026%)

      This would be easier to express if I could use subscripts and better notation. I forget how to do that in HTML but it should still be easy to follow.

      BTW, Where did the 47 in your post come from?

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