New data: You have a one in 5,000 chance of a breakthrough COVID-19 infection (or maybe even one in 10,000)

Originally published at: New data: You have a one in 5,000 chance of a breakthrough COVID-19 infection (or maybe even one in 10,000) | Boing Boing


1 in 5000 every day. That’s like 1 in 14 in a year? I’m keeping my mask on.


If only there was a vaccine and it was free. /s


Yeah, that context is super important. And the article never said what the daily odds are for an unvaccinated person to get it. Surely it’s greater than 1 in 5000, but it still would probably seem small without proper context. Some studies of case rates are showing that vaccines give you roughly a 5:1 advantage against infection (and greater than that against severe outcomes) but if someone said “unvaccinated folks only have a 1:1000 chance of catching the virus” that would not mean what people would think it means.

Edit to add: Santa Clara county in CA is one of the places that reports covid case rates by vaccination status. Their latest dashboard is currently showing that vaccinated folks are getting infected at somewhere around 1/5 or 1/6 the rate of unvaccinated. So the vaccine is definitely helping to reduce the number of cases, but I think that giving people unrealistic expectations on how strong their protection is can be counterproductive. We still want vaccinated folks to be cautious, and making them think there’s only a 1:10,000 chance of them ever getting sick could encourage reckless behavior.


*If you were exposed to the virus every one of those days, which would be unlikely unless you worked in a COVID treatment center or another place with high numbers of infected populations (like at a Trump rally)

Edit: Nevermind - I misread the article. Comment removed.


Where are you getting that from? That was not the situation the article describes at all.


That’s not what the article says. The article seems to indicate that you’ve got a 1 in 5000 chance of getting a breakthrough infection daily if you just do the statistically average stuff with regard to exposure. If you only count the days that you are exposed to the virus the odds would be much worse.


Even at 1 in 10K, that’s still too great a risk for me.

Masks up.



The stat and they way it’s reported in the headline are great for attention grabbing headline, but they’re totally useless and not at all what the actual article says. About normal for NYT Headlines these days. :frowning:

The fact that they qualify the “1 in 5000” or “1 in 10000” based on community transmission in the area is a big part of the clue that the headline is crap. It’s not some absolute protection provided by vaccination.

What the study shows, but isn’t a flashy headline number, is that in the same area a vaccinated person is significantly less likely to be infected than an unvaccinated one. Umm, duh? :slight_smile:

In an area with less overall spread, everyone is less likely to get infected. The vaccinate even more so.

In an area with higher overall spread, the unvaccinated are way more likely to be infected than the vaccinated.

The vaccine still works best when it has very little work to do. If you rarely expose a vaccinated person to the virus, the vaccine protection only has to work rarely. If you drop a vaccinated person into a pool of unmitigated virus spread, the vaccine protection has to work many many more times. Statistically, the increased number of events is more likely to have a failure.

Get your jab. Get your neighbors to get their jab. Get everyone to get the jab. Don’t give the virus a pool of unvaccinated to circulate in and keep coming out to expose a vaccinated person. It’s not that hard, this is how vaccines have always worked. :slight_smile:


I just don’t trust this number, to be honest.

I have friends, local to me where I live, in a highly vaccinated (but not highly vaccinated enough, obviously… maybe mid 60s to low 70s) city, who have gotten breakthrough cases. I’ve seen their vax cards since we started requiring them to be shown. One got their vax on the same day I did and we waved at each other at the convention center. Another was this person’s spouse. I personally know seven people who’ve gotten breakthrough infections. If the 1 in 5000 number was true, even if it was true on a day to day basis in a high community spread… I wouldn’t know 7 people. That’d be a statistical anomaly. And yet, numerous friends of mine in other cities report similar things. I’ve got a friend in Chicago who has said similar… and one in Dallas, Texas… and one in Detroit.

Now we could all be witnessing statistical anomalies, or this could be way more transmissible than we thought and the data’s just not in yet.


Not only is the headline terrible, the actual content is pretty terrible too and is among some of the laziest statistics and interpretation of them in an article that I’ve seen in a long time. A person’s actions and who they’re around change the odds of transmission by orders of magnitude but that’s barely mentioned.


Literally almost every community in the US is experiencing high or substantial community transmission rates per the CDC. That’s over 50 cases per 100,000 people per day.

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That CDC color maps needs more shades of red. While the entire county is red, it’s not all the same shade of red.

Suffolk county MA at 152.75 Case Rate (last 7 days)
Orange county FL at 525.10 Case Rate (last 7 days)

They’re both red, but MA is like a rose red and FL is fire engine red. That’s an improvement since the last time I looked at FL too.

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This is true, there are differeing levels of red, but, the reality is… the red is super dangerous. After you pile on more and more it’s even more dangerous, but we’re already long past a saturation point when it turns red. Nowhere is safe, at all. And 1 in 5000 is just a bs number


You are correct. I read it incorrectly. Appreciate the correction.


What is a “breakthrough” infection?

When someone who is fully vaccinated against COVID-19 gets infected with an active case of COVID-19.


OK - thanks. But what is an “active” case?

I’m not being difficult - I genuinely do not get what these stats are about (and the NYT is behind a paywall).

I thought it was already abundantly clear that the vaccine did not really provide a significantly reduced chance of infection, just a hugely improved protection against its worst effects. So does “active” here mean symptomatic, as opposed to asymptomatic?


As others have alluded to, the article is specific that the chance is per day, which is not they way we normally talk about the chance of catching a disease. Vaccine efficacy percentages, for example, are not measured “per day”. So the BoingBoing summary which doesn’t mention the statistic is per day is misleading.

From the article.

How small are the chances of the average vaccinated American contracting Covid? Probably about one in 5,000 per day, and even lower for people who take precautions or live in a highly vaccinated community.

I think it is a really irresponsible article because it implies that the odds are somehow fixed rather than related to one’s own individual behavior, such as going maskless indoors with groups, such as in a bar. I think both the article and the BB’s misleading summary of it of it will lead people to riskier behavior that is more likely to transmit covid.


It’s the term for vaccinated people catching covid. When they say a vaccine is, say, 66% effective, the 33% of people who catch it are “breakthrough” infections.