Ever since COVID-19 swept across the planet earlier this year, the race has been on to develop a vaccine. Now there are two vaccines that are just about ready to go, but there seems to be quite a bit of reluctance when it comes to the prospect of actually getting it. So let’s talk about it.
The vaccine options
The vaccines that are ready, or almost ready, to go come from Moderna and Pfizer. In general, there are two kinds of vaccines, live attenuated (which contains weakened replicating virus) and inactivated; both the Moderna and Pfizer vaccines are inactivated, meaning they don’t contain any virus particles that could potentially replicate. They are both mRNA-based vaccines. Dry ice is required to maintain storage at -70ºC.
The New York Times reports that, in a blinded trial of the Moderna vaccine, some people who’d been vaccinated did end up getting COVID, but only had mild cases. So far, the vaccine appears to be about 94% effective. The trial included 30,000 participants, about 25% of whom were over age 65. Racially, participants were 63% white, 20% Hispanic, 10% Black, and 4% Asian-American.
Both the Moderna and Pfizer phase 3 clinical trials started Jon uly 27. The Pfizer study included 43,661 participants (as of Nov 18/20) across multiple clinical trial sites in the United States, Germany, Turkey, South Africa, Brazil and Argentina. Efficacy was greater than 94% in adults older than age 65.
Both vaccines require two injections in order to achieve an adequate antibody response.
Were they developed too quickly?
There are a few things to consider here. One is that, while COVID-19 is new, there’s no need to reinvent the wheel; a lot is already known about developing vaccines, so scientists weren’t starting from zero. Another is that a new influenza vaccine comes out every year based on the strains that the World Health Organization predicts will be predominant for that flu season.
A New England Journal of Medicine paper notes that the virus genome was identified on January 10, 2020, at which point, it was off to the races. The first needles were going in arms in preliminary trials on March 16.
A major factor is the huge injection of cash into vaccine development. It means that instead of having to sequentially trial and fail with different options, a ton of labs were able to work on different vaccine candidates all at the same time. There has also been a high degree of collaboration between industry and academia.
While this may seem to be coming out of thin air to us, a review article published on September 4, 2020, in Nature Reviews Immunology shows that science was most definitely on it by that point, so these vaccines didn’t mysteriously appear out of a black box.
Vaccine side effects
Vaccines don’t generally cause a lot of side effects, and serious side effects are very rare. There are a number of side effects that can potentially occur with any vaccine, regardless of what it’s for.
Local injection site reactions like pain, swelling, redness, or itching can happen because you’re injecting something into your tissue, which responds by groaning “me no like.” This can be unpleasant—tetanus, for example, tends to hurt like hell—but it’s not actually harmful.
There’s a very small possibility that instead of a mild “me no like” local reaction, there will be a systemic allergic reaction with hives and breathing issues and the whole nine yards. Anyone giving a vaccine will have epinephrine with them and be trained in CPR, so on the off chance that happens, they’re prepared to handle it.
Any vaccine can also make you feel vaguely ill afterwards. That’s because the whole point of a vaccine is to get your body to produce an immune response, and when your body gets inflamed, it can feel yucky. If your immune response is particularly vigorous, you may get a fever, because a fever is part of what your body does when it’s trying to kick some antigenic ass. All of this counts as side effects, but it’s not so much a side effect as an uncomfortable byproduct of what’s actually supposed to be happening. The good thing is that, unlike the COVID virus, the vaccine isn’t fighting back; your body is going to win. Your body will make antibodies that will kick COVID to the curb if you end up encountering it.
The COVID vaccines
In terms of specific adverse effects with the COVID vaccines, the main issue is related to the vaguely ill-type effects. Science Magazine reports that severe side effects in the Moderna trial were fatigue, in 9.7% of participants, muscle pain (8.9%), joint pain (5.2%), and headache (4.5%). Severe side effects reported in the Pfizer trial were fatigue (3.8%) and headache (2%).
Because there aren’t any COVID virus particles in either the Moderna or Pfizer vaccine, neither can give you COVID.
Herd immunity occurs when enough of the population is immune to a disease, either through immunization or having gotten the disease, that it limits the ability of the infectious agent to spread through the population. This helps to protect people who are high-risk and people who are unable to get the vaccine.
The percentage of the population that needs to be immune to achieve herd immunity depends on how easily the infectious agent is transmitted. Measles is highly contagious, and more than 90% of the population needs to be immune to get herd immunity. The percentage for COVID will likely be lower than that, but there’s no way to know for sure; still, the 90-ish% mark gives a ballpark idea. Low vaccine uptake means no herd immunity.
Cognitive bias and known risk
Our brains have a tendency to get in the way of our decision-making processes. The ambiguity effect is a type of cognitive bias that makes us naturally inclined to go for the “sure thing” rather than something with an uncertain outcome. This is true even when the uncertain outcome is likely to be better than the predictable outcome. This is essentially “better the devil you know than the devil you don’t.”
In this case, COVID is the devil we know, and the vaccine is the devil we don’t. COVID has been kicking the planet’s ass for the last year, but because of the ambiguity effect, that fades away into the background as the status quo. Is it possible that the vaccine could cause worse outcomes than COVID itself? Sure, but the probability is very low. Still, that may loom higher than the loads of people dying because of COVID.
Making decisions about vaccinating
Something worth considering is that while we as the general public don’t have a lot of detailed knowledge about these vaccines, that doesn’t mean that knowledge doesn’t exist. The public health people who have the requisite background knowledge to be able to properly contextualize the data know a lot of a lot more about this than any of us will ever know. And while COVID has made it easy for everyone to play armchair public health expert, that doesn’t mean we’re qualified or capable of doing so. If you don’t know the details on a cellular level of how the immune system mounts a response to an antigen, how vaccines lead to an immune response, and what happens when this particular vaccine enters the body, you’re missing fundamental pieces of information to be able to judge the goodness or badness of this vaccine. That’s why we rely on experts to be able to make those determinations.
So, to vaccinate, or vaccinate? That’s totally up to you, unless some form of mandatory vaccination orders are put in place. I think the important thing to remember, though, is that it’s not a question of balancing a no risk status quo with unknown risk; it’s balancing a known high risk status quo with what appears to be low risk, but with less familiarity. Status quo might still win out for some people, and that’s their choice, but I think people do themselves (and those around them) a disservice by approaching the decision as a zero risk vs. unknown risk proposition.
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