News (recently) that the FDA has granted full approval to the Pfizer vaccine for COVID should relieve the vaccine hesitancy of some Americans. But, by itself, this news won’t be a panacea. Most of my friends and family who have not yet gotten the COVID vaccine are concerned about the long-term, unknown consequences from the inoculation, and the FDA approval doesn’t rule that out.
My friends and family aren’t alone. A new YouGov survey shows that 90% of Americans who have opted against the vaccine are concerned about future side effects. The standard reasoning goes like this: (a) most COVID infections aren’t bad, (b) we can’t rule out terrible vaccine side effects in the future, and (c) the vaccine doesn’t fully protect you, anyway. Conclusion: don’t get the vaccine.
This reasoning is bad. And it’s bad because it leaves out some of the unknown risks. Once all of the unknown risks are properly accounted for, getting a vaccine is the only rational option for most people. … Some people think that the winning strategy is to skip the jab because we are in the dark about the potential for long-term, negative side effects of the vaccine. Even if it doesn’t turn you into a zombie, there is a long history of negative side effects for vaccinations. So, while it’s true that we have pretty good reasons for thinking the COVID vaccine won’t have negative side effects, it’s also true that we don’t have certainty: it’s possible – however unlikely – that there will be terrible long-term consequences of getting the vaccine. But it’s also possible – however unlikely – that there are long-term terrible consequences of getting COVID. The science of disease is pretty advanced and we have good reason to think that, in most cases, people won’t suffer long-term damage from COVID. But we don’t have certainty. There’s always an outside possibility that we’re wrong and, in fact, growing evidence that a minority of people will, in fact, suffer long-term effects of COVID. And so the unknown risks of the disease should be factored into the equation, too.
When we do so, we find that the unknown risks cancel one another out. Worry about the long-term consequences of the vaccine won’t be a reason to avoid it as long as there is also worry about the long-term consequences of the disease. Given that, the rational strategy will be the one that maximizes our values, given what we know, not what we don’t. Unless we’re able to assign probabilities to the unknown risks – something that we’re unable to do in this case – there’s no reason to let the weight of the unknown risks in either direction affect your choice of strategy.
And since we know that the most prominent vaccines reduce illnesses requiring hospitalization by 95%, getting the vaccine will maximize expected value for most people.
Those who forgo the vaccine because they are worried about unknown side effects of being vaccinated are being irrational. They are ignoring the unknown side effects of getting the disease, and these two unknowns cancel one another out. The rational decision will be the one based on the probabilities that we know and the outcomes that we value. On those numbers, vaccination is the winning strategy.
Dr. Justin McBrayer is an associate dean at Fort Lewis College who works on issues in epistemology and ethics. He’s also a writing fellow for Heterodox Academy.