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Related: Editorials & Other Articles, Issue Forums, Alliance Forums, Region Forums15,739 breakthrough COVID-19 cases in Massachusetts; 3,098 reported in one week
BOSTON (SHNS) A total of 15,739 breakthrough COVID-19 infections in people fully vaccinated against the virus have now been recorded in Massachusetts, the Department of Public Health reported Tuesday.
The new total, as of Aug. 21, represents an increase of 3,098 from the previous weeks report and accounts for 0.35 percent of the more than 4.4 million fully vaccinated Bay Staters. Of those 15,739 cases, 571 people have been hospitalized and 131 have died
.
In the previous week, breakthrough cases represented 40 percent of the total. The DPH has cautioned that there are probably more breakthrough infections and hospitalizations among fully vaccinated people than it counts and can report.
https://www.wwlp.com/news/massachusetts/15739-breakthrough-covid-19-cases-in-massachusetts-3098-reported-in-one-week/amp/
PSPS
(13,512 posts)Lucky Luciano
(11,242 posts)40% of the cases were breakthroughs. Also 131 out of 15k died or about 0.85% of the known breakthrough cases died. There is not enough data here to conclude efficacy, but 99.7 is high. What seems quite clear is the need for boosters.
PSPS
(13,512 posts)LisaL
(44,962 posts)NT
Phoenix61
(16,954 posts)The new total, as of Aug. 21, represents an increase of 3,098 from the previous weeks report and accounts for 0.35 percent of the more than 4.4 million fully vaccinated Bay Staters.
LisaL
(44,962 posts)To calculate vaccine efficacy, you have to know the number of infected among vaccinated and un-vaccinated. Those are the numbers used to calculate efficacy.
PSPS
(13,512 posts)How can the un-vaccinated be included in any vaccine efficacy measurement? Do you include people who don't use seat belts when measuring how well a seat belt works?
Ms. Toad
(33,915 posts)Vaccine efficiency is determined as measured against the placebo (being unvacciated).
A 95% efficience (the original reports) was obtained based on this data:
>43,000 participants (evenly split into vaccine v. placebo). 162 cases of COVID 19 in the placebo group;8 cases in the vaccinated group.
https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-conclude-phase-3-study-covid-19-vaccine
The way vaccine efficiency is actually measured:
8 cases among vaccinated individuals/162 cases among unvaccinated individuals = .04938 (about 5%) as many cases as in the placebo group = efficiency of 95%. (100%-5%)
The calculation you are doing is a snapshot in time, and depends totally on the exposure, the mitigation measures in place, the viral load in the community, etc.
Applied to the study data - it would not only make the efficiency of vaccines well over 99% - it would also make the efficiency of doing nothing at all over 99%
8 cases/21500 vaccinated = .00037 => 100%-.037% = 99.963%,
162 cases/21500 unvaccinated= .00753 =>100% - .753% = 99.247% effective.
If not being vaccinated is 99.247% effective in fending off COVID, why bother with vaccinations at all?
And yes, the effectiveness of seatbelts is measured exactly the same way: Injuries to seatbelt users/injuries to people not wearing seatbelts.
Educate yourself, rather than digging a deeper hole.
Leith
(7,802 posts)Post number 35 is a halfhearted try to explain it.
From the WHO website
So, for example, lets imagine a vaccine with a proven efficacy of 80%. This means that out of the people in the clinical trial those who received the vaccine were at a 80% lower risk of developing disease than the group who received the placebo. This is calculated by comparing the number of cases of disease in the vaccinated group versus the placebo group. An efficacy of 80% does not mean that 20% of the vaccinated group will become ill.
Yes, posters should use the term "effectiveness" instead of "efficacy" because the numbers are clearly showing that being vaccinated is an advantage to getting covid and experiencing milder symptoms. And it appears that some posters are using the ordinary dictionary definition of efficacy instead of the scientific definition (like the decades long misunderstanding of the scientific definition of theory ). That does not change the fact that we are all on the same page. Quibbling about which word to use is not the point.
Demsrule86
(68,352 posts)PSPS
(13,512 posts)LisaL
(44,962 posts)NT
Don't mean to be derogatory, but - that's just ...
(not a chicken little here - about either the vaccines, or the delta variant. vaccination is still by far our best option. but - new information must be acknowledged and accounted for.)
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PSPS
(13,512 posts)stopdiggin
(11,095 posts)if you don't understand these things, then just quit.
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PSPS
(13,512 posts)Maybe you're confused because the figures are for fully vaxxed people, not the population at large. This means vaccination is the way to go. Otherwise, please enlighten all of us with your wisdom. Thanks!
marybourg
(12,540 posts)And my electronic calculator agrees. In fact I get 0.3636363636. Isnt there a name for that?
GulfCoast66
(11,949 posts)marybourg
(12,540 posts)rateyes
(17,438 posts)It, also, a rational number since it can be expressed as a fraction with integers in both the numerator and denominator. In this case 4/11.
LisaL
(44,962 posts)Efficacy of the vaccine is not calculated this way.
Phoenix61
(16,954 posts)The new total, as of Aug. 21, represents an increase of 3,098 from the previous weeks report and accounts for 0.35 percent of the more than 4.4 million fully vaccinated Bay Staters.
That has nothing to do with how vaccine efficacy is calculated.
PSPS
(13,512 posts)How can the un-vaccinated be included in any vaccine efficacy measurement? Do you include people who don't use seat belts when measuring how well a seat belt works?
Lucky Luciano
(11,242 posts)Yes of course! Probability of serious injury or death when wearing a seat belt compared to not wearing the seat belt indicates whether seat belts help! They do.
PSPS
(13,512 posts)SCENARIO 1 (wrong way): 100 people get in an identical crash. 5 are wearing a seat belt. 55 people are seriously injured and none of those was wearing a seat belt. Therefore, seat belts are 45% effective at preventing serious injury.
SCENARIO 2 (correct way): 100 people get in an identical crash. 5 are wearing a seat belt. 55 people are seriously injured and none of those was wearing a seat belt. Therefore, seat belts are 100% effective at preventing serious injury.
In this Covid discussion, we're seeing that, among vaccinated people, over 99% have had no breakthrough infections. In other words, get your damn vaccination!
Lucky Luciano
(11,242 posts)You can only count efficacy if one is exposed to a proper dose of virus. Not all people are exposed to the virus. The best way to compare is what percent of unvaccinated get sick to the percentage of vaccinated that get sick. You would strongly hope that the vaccinated have a much lower proportion getting sick and that is indeed the case but it is not 99.7% effective. At this stage, it appears to be around 60%, which helps a ton, but is not the 90-95% number touted early on which may be correct up to couple months after vaccination. It does, unfortunately, appear to wear off after more time though.
PSPS
(13,512 posts)Lucky Luciano
(11,242 posts)If you cite the Israeli studies and some others, they will give ranges of 40-60% efficacy after 6 months have passed.
There does not exist any study citing 99.7%. That would be an incredible number and there would be only a handful of breakthrough infections if true - meaning if 1000 vaccinated people were exposed to a significant dose that would definitely sicken an unvaccinated person, only three get sick on average. That is not the case.
The good news is that it does seem that your are three times less likely to get sick if you are vaccinated and thats a win, so people need to get vaccinated.
The Magistrate
(95,237 posts)The article states the number of cases in vaccinated persons is 0.35% of the total four million, four hundred thousand vaccinated persons, or about three in one thousand vaccinated persons.
Of those cases in vaccinated persons, five hundred seventy-one, or about one in thirty has been hospitalized, or about one in ten thousand vaccinated persons.
Of those five hundred seventy-one vaccinated persons hospitalized, one hundred thirty-one have died, roughly one quarter of the number hospitalized, or between two and three per one hundred thousand vaccinated persons.
That the number over one week is a fifth of the total is worth some attention, particularly if that trend continues or accelerates. It still has a great deal of room to expand before it gets into hailing distance of rates of infection, hospitalization, and death among an un-vaccinated population.
LisaL
(44,962 posts)Efficacy is not calculated this way.
There are millions of un-vaccinated too, and not all of them have gotten sick.
The important number here is that 40% of infections are breakthrough.
The Magistrate
(95,237 posts)I am not calculating overall efficacy, I am calculating a vaccinated person's possibility of serious outcomes --- hospitalizations and deaths.
Regarding overall risk:
Approximately one third of the state remains unvaccinated.
If cases among the vaccinated are two fifths of a week's total, then three fifths are among the unvaccinated.
Therefore the current risk of infection to an unvaccinated person is about three times as great as that to a vaccinated person.
Lucky Luciano
(11,242 posts)I dont know how efficacy is calculated, but if I had to do a back of the envelope calculation, I would say:
36% are not vaccinated and 64% are.
Say the total population is 10000, so 6400 are vaccinated.
Say 100 got infected. 60 are not vaccinated and 40 are.
We then see that for the vaccinated people, 40/6400 or 1 in 160 got sick.
For the unvaccinated, we see 60/3600 or 1 in 60 got sick.
So, I read this as the vaccine reducing your chance of getting sick as described above from a 1 in 60 chance to a 1 in 160 chance.
So I would say efficacy is:
1 - (1/160) / (1/60) = 1 - 60/160 = 62.5%.
Thats my back if the envelope where I dont really know the definition of efficacy.
The Magistrate
(95,237 posts)Lucky Luciano
(11,242 posts)LisaL
(44,962 posts)Breakthrough infections now represent 40% of infections in MA, per the article.
Phoenix61
(16,954 posts)The new total, as of Aug. 21, represents an increase of 3,098 from the previous weeks report and accounts for 0.35 percent of the more than 4.4 million fully vaccinated Bay Staters.
LisaL
(44,962 posts)It has nothing to do with vaccine efficacy.
PSPS
(13,512 posts)How can the un-vaccinated be included in any vaccine efficacy measurement? Do you include people who don't use seat belts when measuring how well a seat belt works?
Ms. Toad
(33,915 posts)in measuring the efficiency of seatbelts. Efficiency measures how effective the safety measure is compared to doing nothing. As for vaccines - how many cases of COVID in vaccinate dpeople compared to how many cases when we do nothing. For seatbelts - pick a bad outcome (death, for example) - efficiency measures how many deaths for seatbelt wearers v. how many deaths would happen anyway..
Efficiency = bad outcomes with the proposed safety measure/bad outcomes when doing nothing.
For seatbelts: Deaths while wearing seatbelts/Deaths while not wearing seatbelts.
For vaccines: Death or serious illness (the study endpoints) with vaccines/death or serious illness for unvaccinated people.
Way too many people on DU need a high school mathematics class.
NT
PatSeg
(46,804 posts)That is a rather disturbing number, especially if those people were fully vaccinated. I am afraid that the nutters out there will use statistics like that as another excuse not to get the vaccine.
cadoman
(792 posts)We have science on our side.
PatSeg
(46,804 posts)to get vaccinated, they are absolutely livid about the masks. You'd think it was a damn death sentence.
GulfCoast66
(11,949 posts)Than dying of Covid if vaccinated.
I assume this OP was intended to cause concern and I get it. But for a math guy it does the opposite.
Not than Im that much of a math guy, but I took statistics decades ago!
131 deaths out of 4.4 million vaccinated people is and over 99.5 percent chance of not dying if you get Covid and are vaccinated. And since most vaccinated people have no or mild symptoms and never get tested it is probably an even lower chance.
Im certainly not recommending to unmasks and businesses as normal. I still mask and am careful of my surroundings. But I know my risk is minimal now. Unlike last year.
uponit7771
(90,225 posts)mucifer
(23,374 posts)Also age and preexisting disease and age. Are as many pregnant women hospitalized with the vaccine as without etc.
PatSeg
(46,804 posts)without those numbers as well. Unfortunately, all some people will see is "131 deaths" among the vaccinated.
marybourg
(12,540 posts)it doesnt matter how many didnt die, but thats a pretty impressive vaccine. Thats a death rate of .0029%.
PatSeg
(46,804 posts)For the person who dies, the statistic is 100%, but of course it is reassuring for the rest of us that the death rate is so low.
GulfCoast66
(11,949 posts)Your chance of dying in a car crash is higher in that state than dying of Covid if vaccinated in Massachusetts!
I dont care enough to do the math but in 2020 347 residents of Massachusetts died in car crashes. 4.4 million of there residents are vaccinated in a population less than 7 million. And kids under 12 cant get vaccinated. Yet only 131 vaccinated people have died. 2021 is not over certainly, but its doubtful that the final number of vaccinated people dying will exceed car crashes.
I alway like posts which give me even more trust in the vaccine.
Im still masking and being careful. A year ago it was because I did not want to die. Today its because I dont want to be sick and potentially kill an older unvaccinated person. Although my concern about the unvaccinated is quickly dying.
LisaL
(44,962 posts)In which universe?
Phoenix61
(16,954 posts)this is what you see. A higher percentage of people who are vaccinated with the virus because they are a significantly larger portion of the population. Its counter intuitive but its how it works.
GulfCoast66
(11,949 posts)If the population was 100% vaccinated then 100% of the cases would be vaccinated.
The number to look at is deaths and hospitalization among the vaccinated population.
I never assumed back in March when I got the vaccine that I could no longer catch the virus. We knew it was 90% or so effective which is really good for a vaccine. But not perfect.
What I hoped, and now know is that it reduces my chance of dying to level more associated with other diseases Im at risk of and a few of the activities I undertake in my daily life.
Demsrule86
(68,352 posts)LisaL
(44,962 posts)40% is the number right there in the OP article.
ProfessorGAC
(64,425 posts)Per "Our World In Data", 65.5% of eligible recipients in MA are fully vaccinated, 74.8% at least one dose.
This means 25.2% of the population is responsible for 60% of new cases.
40% ÷ 0.748 = 0.5348
60% ÷ 0.252 = 2.381
That makes being unvaxxed increase one's odds of infection to 445% over being vaxxed.
I don't understand how you can't see that this is a good thing.
stopdiggin
(11,095 posts)But the number of 'breakthrough" cases in the vaccinated - can't be in any way construed as good news! What do you think the article was talking about? Boy - talk about a hijacked thread!
ProfessorGAC
(64,425 posts)It's unnecessary fear mongering that willfully ignores the silver lining while only seeing the dark cloud.
If they're both there, it's ridiculous to ignore one of them.
And, it's clear you didn't think through the math I just showed.
A high percentage of breakthrough cases when 70% of the population is vaxxed is a tautology.
Extend the numbers.
- 100% vaccination rate
- 1 Case
- 100% of cases are breakthrough
Of course the % of cases as breakthrough goes up as vaccination % increases.
And, nobody is hijacking any thread here.
This is an open discussion forum, and my point was obviously directly related to the point.
Not sure how you missed something so obvious.
stopdiggin
(11,095 posts)is that prior to delta - breakthrough cases had been exceedingly rare period. Now you can contort this into some manner of silver lining if that is your wish - but the point of the article was that these are some very concerning numbers and findings, that were not at all in the picture a fairly short time ago. I am not into fear mongering either, and totally concur that the vaccines have been and (for the most part) continue to be hugely effective. We should be selling "the shot' (and possibly 'the booster') to every soul that is willing to listen. But the 'breakthrough' aspect that is rearing it's ugly head (and that is in fact what we are talking about here) - particularly with the proposed ability for those breakthrough cases to become infectious and spreaders on their own - is a serious development (and public health consequence) indeed, and certainly not something that we should be attempting to gloss over - purely in an effort to sugar coat the news for the nervous public.
Scrivener7
(50,774 posts)Azathoth
(4,603 posts)On the one hand, it suggests that breakthrough infections are less common among the vaccinated. On the other, it suggests that vaccinated people are getting infected at a rate that is mucher closer to the rate of unvaccinated infections than is comfortable.
It also suggests that 1) the lower mortality rates among unvaccinated may soon start to climb back to parity and 2) the liklihood of a variant emerging that is capable of full vaccine escape is now exponentially higher given that there are major infection rates among people who have vaccine-induced antibodies, thereby creating a vast reservoir of environments where the virus is experiencing selective evolutionary pressure.
ecstatic
(32,567 posts)That's the part that is never mentioned in these articles.
Azathoth
(4,603 posts)Given that rising breakthrough infections indicate some combination of waning resistance and increasingly vaccine-resistant strains.
First we'll get asymptomatic breakthrough infections, then mildly symptomatic breakthrough infections, then inevitably severe breakthrough infections.
The only question is how long we can use boosters to keep resetting this cycle before we need a new generation of vaccines.
genxlib
(5,507 posts)Finding a lot of breakthrough cases is more concerning if they are symptomatic and serious. A lot less concerning if they are not.
One question that always pops into my head in these scenarios is the demographic of who is testing and who is having serious cases.
For instance, the back to school period could be cause for testing a bunch of asymptomatic people who would have never been found otherwise. Which is something that is going to happen whenever you have a wave of testing of healthy people. It is important data for the prevalence of the virus and potential spread but doesnt necessarily mean we should be more worried about catching it
Similarly if the hospitalizations and deaths skew older and sicker, it tells us more about the effectiveness of the vaccine
Klaralven
(7,510 posts)Which means that 60% of the cases are in the 35% of unvaccinated people.
Let Pv be the probability of getting Covid if vaccinated, and Pu if unvaccinated. Let C be the number of cases, and N be the number of people.
Then 0.4*C = Pv*0.65*N and 0.6*C = Pu*0.35*N
After a bit of algebra, Pu / Pv = (0.6 / 0.35) / (0.4 / 0.65) = 2.8.
So unvaccinated people are about 3 times more likely to catch Covid than vaccinated people.
Of course this calculation assumes that both vaccinated and unvaccinated people are equally exposed, while some of the protection of vaccinated people may be due to the fact that they are more careful and less exposed.
Hugin
(32,778 posts)and such a relatively small number of breakthrough cases other confounding considerations enter the equation which are related to vaccinations, rather than the efficacy of the vaccines themselves.
Setting aside co-morbidities, there are also a small number of vaccination misfires to account for. Where someone thinks they have established immunity, but, for some reason, haven't. This is one way the two doses required for the mRNA is good. It reduces the likelihood of misfires considerably. One of those shots is going to take. This is also why in my humble opinion a booster should have been planned all along while the virus is in the massive circulation stage.
No system is perfect and successfully vaccinating someone is no exception. It is a complex process and the overall rate of success would seem to be a damn miracle all things considered.
Thanks for doing the probability math on the vaxx'ed vs unvaxx'ed rates.
Klaralven
(7,510 posts)to vaccination based on other articles that affirm that vaccination is more effective at preventing hospitalization and death than catching a case of Covid.