A 900-person Covid delta cluster in Massachusetts includes 74% vaccinated people

Originally published at: A 900-person Covid delta cluster in Massachusetts includes 74% vaccinated people | Boing Boing




Covid-19 delta variant is “so contagious that it acts almost like a different novel virus, leaping from target to target more swiftly than Ebola or the common cold.”

Expect that “lock down & mask mandate” any day now.


Thanks, Covidiots.


When do we get vaccine 2.0, I wonder? Shouldn’t take much to fold the delta into the dose.


My first thought on reading this article was that this thing has learned how to infect and multiply within vaccinated hosts. It is not making them terribly ill yet, but it is getting around the vaccines and multiplying. Every duplication in a vaccinated host is one that faces the evolutionary pressure of a vaccinated immune system. This is exactly how you generate resistant bacterial strains in the lab (well, not using people, using petri dishes, but the point holds.) I cannot say that this is how the next variant arises, but I will bet it will be in a situation of this sort. For the bazillionth time, it did not have to be like this. Not in the US of A, it did not. We did this to ourselves and are reaping our whirlwind. The pressure on the virus is to find more vulnerable cells to multiply in. The easiest way is to find it’s way into the lungs, which it is currently having a hard time doing. But it is “trying,” I assure you. And given enough tries, it will.


The health consequences of the delta variant may not be so bad for the fully vaccinated (especially for those who got mRNA jabs), but it’s obviously more contagious for everyone. Which is why we need to continue wearing masks indoors and get more people vaccinated. Unfortunately, the Know-Nothing 27% seems intent on rejecting those measures in favour of becoming breeding grounds for more powerful variants and/or sacrificing themselves for their death cult.


All the reports I’m seeing point out a few problems. Just like the first go-round, they’ll probably need to set a priority. There’s not a lot of test data, and as was just pointed out, we’ve got multiple variants out there because people just keep pretending this is over. I saw a report this morning that said even if the elderly were made the priority, they’re not sure about the severity of response to a vaccine that targets the new variants, so they don’t want to make a bad situation worse in terms of symptoms in people who are already at risk. Finally, the supply is already an issue, and people getting a third dose when there are so many in the world who are waiting for their first one, is not a good look, to put it mildly.


Parents in Augusta County VA are celebrating that the school board voted unanimously to make masks optional for the coming year for students, faculty, staff, visitors, etc. Rockingham will follow suit shortly, I suspect. We are already getting crushed at my office (my full schedule, very full, is 25 patients. I am currently averaging 30-35.) When schools open with no masks (I mean, optional? Right.) we will get buried very quickly. Not looking forward to it, at all.


Don’t sweat the “74% vaccinated” statistic too much – it’s actually exactly what would be expected in a population with a large percentage of vaccinated people.

Let’s say there’s 1000 vaccinated people and 10 unvaccinated people. If you have a 20% chance of getting the virus if you’re unvaccinated and a 0.5% chance of getting it if you’re vaccinated, then:

1000 * 0.005 = 5
10 * 0.2 = 2

Percentage of cluster that’s vaccinated: 5/7 = 71.4%

Should we be concerned? In general, yes, this is no time to let up on our precautions. But we should not be concerned about the percentage of infected people who are vaccinated, we should pay attention to the percentage of vaccinated people who get infected.



This variant was first detected in India in October 2020, when the vaccination rate there was practically zero, and quickly became dominant there well before 5% of folks had received their first shot. I wonder how much it has evolved since then, and how much any given variant has to change before its given a new name?


Sorry to hear that, Doc. I’m sure you’re aware already, but I looked up the percentage vaxxed in that county where they’ve made that decision: 50.02% with at least one dose, 46.82% fully vaccinated. At this point in time that doesn’t bode well for higher numbers during the first semester of school. I’m not sure what those parents are celebrating, unless they actually like the idea of overloaded ICUs.


Considering the actual percentages of vaxxed vs unvaxxed, (not reported for this particular case) that 100:1 ratio is insanely optimistic. Those numbers hold up when dealing with measles outbreaks and arguing with antivaxxers that “most of the infected were vaccinated, so it doesn’t work!” but here I suspect it is rather less so.


And, of course, much less than that in school age kids. Yeah, fun times ahead.


Is that a reasonable assumption though? According to google in Massachusetts only 63.7% of the population is fully vaccinated, not 99%.

Obviously the vaccinated are far more protected against infection but given the information presented in this article I wouldn’t bet on the ratio being quite what you describe.


162,000,000 vaccinated, 35,000 breakthroughs.

That’s an infection rate of 0.000216049382716%



35k per week. Is it huge raw numbers? Not yet. Is it cause for concern? You bet your ass.


Yeah, I absolutely don’t think that the example numbers I used are in any way realistic; I mostly used them to demonstrate how a similar number could be generated and to highlight the principle that the ratio of unvaccinated in the infected sample isn’t the germane statistic, and in fact can behave contrary to what one might expect as an indicator.


But the vaccinated are largely (not entirely, I grant) merely carriers. If only they could target it away from the vulnerable (kids, immuno-suppressed, etc) and target it directly towards those anti-vax / Covid deniers. (Do I need a /s tag?)

But they can’t, which is why everyone being vaccinated is the only protection, ultimately. Which won’t happen, of course, because of these fuckwits, so roll on the next variant…

ETA and of course @gracchus and @docosc said it all first