izard

Recent (end of 2024!!) social media discussion:

Someone: I won't do covid-19 boosters, they cause myocarditis. 3 upvotes, 8 downvotes.

Pro-vaxer: Here is a link to a study proving that covid-19 vaccine causes myocarditis, but covid-19 causes myocarditis more often.
15 upvotes, no downvotes.

Me: Could you please explain why you claim that this study proves that "covid-19 vaccine causes myocarditis, but covid-19 causes myocarditis more often", while the study does not explore frequency of myocarditis after covid-19 and after the vaccine at all? All the study does is demonstrating that post-vaccine myocarditis is less harmful than post-covid19 one.
6 downvotes, no upvotes.

Pro-vaxer: Oh, sometimes stupid antivaxers even read the linked studies! But they can't comprehend what they read, this is the problem. You see, even the abstract says: "Patients with post–COVID-19 mRNA vaccination myocarditis, contrary to those with post–COVID-19 myocarditis, show a lower frequency of cardiovascular complications than those with conventional myocarditis at 18 months."
You probably just read a part of the summary, which says "Post-vaccination myocarditis after vaccination with anti-COVID vaccines has a milder course and a lower risk of developing complications in the long term."
You think I made an error, but the error is all yours!
0 downvotes, 1 upvote

Me:
Let's think step by step:
1. From your first comment: "covid-19 vaccine causes myocarditis, but covid-19 causes myocarditis more often"
Let's assume P(A) the probability of getting myocarditis from the vaccine, and P(B) the probability of getting myocarditis from COVID.
So, your statement is P(A) < P(B).


2. From your second comment, the first quote from the abstract, which, in your opinion, I misunderstood. "Patients with post–COVID-19 mRNA vaccination myocarditis, contrary to those with post–COVID-19 myocarditis, show a lower frequency of cardiovascular complications than those with conventional myocarditis at 18 months." Please re-read it again. It says nothing at all about P(A) and P(B). All it says is that P(C|A) < P(C|B), where P(C) is the probability of cardiovascular complications 18 months after the diagnosis of myocarditis.
1 downvote, 0 upvotes, no responses so far.

The scary part is that Pro-vaxer is likely a doctor, based on his (or her) other comments. Confirmation bias maybe really tough.

In an elementary school my 7yo son is attending they plan to start vaccinations ASAP and mandate them.

So I carefully reviewed official data from the FDA advisory board meeting and vote.

I don't doubt effectiveness of the vaccine. FDA board members are professionals so I'll just rely on their data. For 10000 vaccinations 2.0 covid hospitalizations are going to be prevented. (Assuming incidence rate grows a bit comparing to September peak. But so far it only went down). Also this is an average for the whole set of 6-11 year olds, for a healthy 7yo odds should be a bit smaller.

Safety data is more interesting. Regarding the most important concern, they estimate 1.5 pericarditis/myocarditis hospitalizations per 10000 5-11yo boys. Risk for girls is ~0.1x of that so vaccination would make sense. As 1.5 and 2.0 are averages, their respective CIs may actually overlap.

Why then they voted yes 17/18? Dr. Eric Rubies, a voting member, summarised: “It should be a personal choice. If I had a child who is a transplant recipient, I would really want to be able to use the vaccine. …. We are worried about side effects we can’t measure yet. … But we are not going to learn how safe this vaccine is [for children 5-11] unless we start giving it. That’s just the way it goes. That is how we found out about rare complications of other vaccines, so I think we should approve it. ”

Almost every voting member acknowledged before the vote that this decision is a very close call. However after they voted, the tone instantly changed to being 100% confident, as quoted by CNN and likes.