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Way back in May 2020, we published a two-article series on risk assessment in the age of the coronavirus. In Part I of "How do I decide what's safe," we ditched the question "Is it safe?" in favor of two new questions: "How safe is this relative to other activities?" and "Can we modify this activity to make it safer?" In Part II, we developed a set of questions to gauge the risk of any given activity and came up with several ways that activities could be made less risky.
Now we're in a new stage of the pandemic. More and more people are being vaccinated, which clearly makes everybody safer. But how safe? What activities are safe if you're vaccinated? If you're not vaccinated, do you still have to follow all the old rules, or does your risk assessment change when lots of people you encounter or want to hang out with are vaccinated? Finally, what do you say to people in your life who don't want to get vaccinated? What do you say, as a teacher, to your students — to those who are over 16 and therefore will be eligible for vaccination soon, and to those who are not yet 16 and won't be eligible for several months? How do you feel about being in classrooms with unvaccinated students, even if you're vaccinated yourself?
It all seems pretty complicated. But the tools we developed back in May 2020 are still useful even with the new twist introduced by vaccination. Take this one: What activities are safe if you're vaccinated? You can use exactly the same set of criteria we listed previously:
- How big is the space you're in and how many people are in it?
- What's that space like?
- How long are you spending in that space?
- What are you doing in that space?
- How likely is it that there's an infected person in that space?
You'll remember that the rationale behind these particular questions was that in order to become infected with the coronavirus, you would have to inhale an infectious dose, probably several thousand viral particles at least. The risk of inhaling that many particles went up if you were indoors, in an unventilated space, with lots of people, especially if you were all shouting or singing.
If you're vaccinated, the risk of contracting a symptomatic case of COVID-19 goes down dramatically — by 80 to 95%, depending on which vaccine you received. ("It's Raining Vaccines" has an explanation of how the effectiveness of the vaccines was determined.) The clinical trials used symptoms as an endpoint, so they didn't actually establish that the vaccines prevented infection, just that those infections, if any, were mild enough to pass unnoticed. So, for a group consisting solely of vaccinated people, the risk assessment questions basically become moot. None of you is likely to have an infection at all, and if you do have an asymptomatic infection, no one is likely to become sick as a result.
You're vaccinated ... now what?
Alrighty then! You're vaccinated. You're good to go, you can do whatever you want, right? Well, not so fast. The situation becomes considerably trickier if we're talking about a group in which some people are vaccinated and others are not. While the vaccinated people are very unlikely to get sick, the unvaccinated people can still pass the virus to each other, and there's a risk (although it is increasingly thought to be a small one) that a vaccinated person could have an asymptomatic, but nevertheless transmissible, infection that could spread to an unvaccinated person. So as long as the virus continues to circulate widely (which it is still doing — daily cases in the U.S. are still over 65,000, a bit higher than the levels experienced during the summer surge), the virus will continue to circulate within mixed groups.
And not only is the virus still circulating at relatively high levels in many parts of the U.S., new, more transmissible variants are quickly becoming the predominant circulating strains. What this appears to mean, unfortunately, is that the benefit of having increasing numbers of people vaccinated is being diluted by the fact that the virus is spreading more effectively among those who aren't vaccinated. Even worse, evidence is even beginning to emerge that the new variants are more likely to infect — and be spread by — children.
Consequently, getting as many people vaccinated as possible, as quickly as possible, is more important than ever. For schools to open safely, or for any gatherings that include vaccinated and unvaccinated individuals to resume, the proportion of people who are vaccinated needs to rise to the point where chains of transmission become difficult to maintain.
What to say to people who don't want to get vaccinated
Which brings us to that final question: What to say to people who don't want to get vaccinated? As it becomes clearer and clearer that high levels of vaccination are really the only way we're going to get back to normal without putting people at risk, how do we convince people that getting the vaccine is safe for them and vital for their community?
I had an interesting conversation recently with someone who was leaning against being vaccinated, which you might find useful if you have people in your life who are reluctant about or even opposed to vaccination, but are willing to talk to you about it.
Now, bear in mind that I live in San Francisco, where compliance with public health guidance has been high throughout the pandemic. San Francisco has one of the lowest per capita death rates of any metro area in the U.S. (second only to Seattle) and has already managed to vaccinate almost 50% of its eligible population. If you follow neighborhood social media channels here, you're vastly more likely to find people trading tips on where to score a vaccination appointment than expressing any doubt about vaccines. All this to say, I don't get a lot of opportunity to talk to people who are reluctant, much less opposed, to being vaccinated. But I did run into one, and the conversation was instructive.
My friend is a small business owner and often chafes at rules and regulations. When I asked him recently, when the gym re-opened at very limited capacity after months of being closed, about getting vaccinated, he said he thought he'd skip it. Why? I asked. His first answer was that the technology of the RNA vaccines was new and unproven. He added that his own risk of getting really sick from COVID-19 was low because he's young and healthy. Evidently he assumed implicitly that the risk from the vaccine was higher than the risk from the disease. This isn't surprising: we humans have difficulty with comparing very small risks, especially theoretical ones. The difficulty is compounded here by our tendency to discount risks that we think we can control (contracting the virus) while exaggerating risks that we feel are out of our control (even speculative ones, such as the emergence of long-term risks of vaccination in the future).
But we can overcome these difficulties by thinking carefully about reliable evidence. With regard to the current coronavirus vaccines, we know that the risk of an acute severe side effect is virtually zero. There have now been well over one hundred million vaccine doses administered in the U.S. alone, with a very small number of allergic reactions, none of them fatal. Meanwhile, the risk to a 40-year-old man of hospitalization from COVID-19 is just under 5% and the risk of death is 0.2%. That's low, but it sure ain't nothing, and it's orders of magnitude higher than the risk from vaccination.
More important than the numbers to my friend, though, was the high value he places on personal choice. "If I choose not to be vaccinated, that's on me," he told me. "And the same is true of all other adults. If they get vaccinated, I'm not putting them at risk. If they choose not to, they've accepted the risk, just as I do."
An interesting turn
This is where the conversation took an interesting turn. I said, "But what about the people who can't be vaccinated, or for whom the vaccine won't work?" This really caught his attention. "What do you mean there are people who can't be vaccinated?" I told him about people with severe allergies to vaccine components, who are advised against being vaccinated. And there are even more people with weakened immune systems, those with auto-immune diseases, or recovering from chemotherapy, or with some chronic infections such HIV, who can get the vaccine, but will mount less of an immune reaction and probably be less well-protected than people with healthy immune systems. And of course, since their immune systems are compromised, they are at the highest risk of bad outcomes if they do contract the coronavirus.