The Buffalo Bills began their 2021 training camp on Wednesday, but two members of last year’s starting offensive line won’t be available to practice yet because of the coronavirus. Dion Dawkins and Ike Boettger have both landed on the COVID-19 reserve list, according to Bills GM Brandon Beane.
Beane said that, between those two players, one of them had symptoms, while the other did not. All in all, the Bills are managing five cases of COVID-19 right now, and two of them were “breakthrough” infections where a vaccinated person caught the virus.
Beane added that every Bills coach is vaccinated, and 80 percent of Bills players had taken at least one dose of a vaccine to this point. If it seems a little surprising that almost half of the Bills’ infections are in vaccinated people, Bayes’ Theorem explains that situation.
To understand how Buffalo’s situation plays out statistically, we’ll examine a hypothetical scenario. Let’s take a population of 100 people and give them roughly the same vaccination rate as the Bills—so if every coach is vaccinated, and 80 percent of players are vaccinated, we’ll meet in the middle at a 90 percent vaccination rate. If 90 of these 100 people in the population had a vaccine and ten did not, it could be possible that two vaccinated folks tested positive and three unvaccinated people carried the virus. Because the vaccinated population is so much larger than the unvaccinated population, the chance that a person with COVID-19 also had the vaccine is statistically higher.
How that situation works out, in effect, is that 2/90 or 2.2 percent of vaccinated people would be infected, and 3/10 or 30 percent of unvaccinated people were infected—demonstrating the efficacy of the vaccine! That’s your math lesson for the day.
Keeping in mind the NFL’s updated COVID policies, if either Dawkins or Boettger were vaccinated, then they’ll be able to return to practice shortly, especially if asymptomatic. We also don’t know at what point they joined the list, so they may have already been working through their symptoms for a few days anyway. At any rate, expect to see many of these updates over the next few months as the virus continues passing around NFL rosters.