Last week's update

* Please read the comments, as many of the critiques
and questions are answered there.
* Note that now it's for ages 20-49. See below ⬇️

Printed out calculations:

Data sources:

cases numbers:…
(2 rightmost columns)

vax and population numbers:…

recovered (=confirmed ago) numbers:…

% vax / recovered (that's why 20-49):
Basic explanation about vaccine efficiency concept, methodology and discussion of possible biases (read through the thread there):
More detailed methodology discussion
What if we don't remove recovered from unvax, and take all unvax regardless of whether recovered?

the vaccine efficiency w.r.t. to this group is 0.
Because recovered are much more immune, so the average immunity of this group will be as that of fully vax.
printed out calculation.
same as above, the only difference is that I didn't remove recovered from unvax.
The 0 efficiency resulted when approximately 1/3 of unvax were recovered. that's enough to make the vaccine inefficient compared to this group.
What would be the efficiency if we compare fully vax to unvax & recovered?...
BTW the Israeli authorities start to understand that too.
Just took them some time.. They are lagging behind me by 2-3 weeks

That was 2 weeks ago >>…
And that's now

You see how numbers continue to drop? That's my graph…
Don't bother if the number they give 40% or 50%.
It depends on age stratification and other partitions.
The most important part is that it's declining sharply, and it's way less than 95%. Preventing infection, symptomatic illness, hospitalization and deaths.
An update from today.
A respected Israeli journalist complained why they just give the numbers without explanation.
Anyway, those are the current numbers the authorities believe for vaccine efficacy in Israel - very similar to mine:

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More from @MatanHolzer

23 Jul
Vaccine efficacy in preventing covid hospitalizations and deaths coming from Israel:
Is it reliable?

The answer is NO.


No differentiation between hosp./death *due to* covid vs. *with* covid.
"with" numbers are affected by testing policy, which differ in vax vs. unax⬇️
First, we must understand the difference between hospitalization / death *due to* covid vs. *with* covid.

By "*due to* covid" we mean that covid19 illness was the cause of hosp. and death. The patient developed respiratory syndrome, that's why he/she hospitalized, and died.
There is a very different scenario, in which somebody is hospitalized due to some other reason, but upon admission he/she was tested for the virus SARS-CoV-2, and found positive. Then he/she is assigned to covid department (to prevent infecting other patients).
Read 34 tweets
21 Jul
Israeli physicist Eli Waxmann ("Neil Ferguson from Ali Express"), always been wrong, continues with fear mongering.
Now he predicts many deaths of unvaccinated
But they are mostly children, and healthy not-old adults. And he predicts as many death as pro vax waves... >>
His models are wrong mostly due to two wrong assumptions:

1. Asymptomatic illness is rare (25%), and the authorities know about most of those who have been infected. This way he get a very high death rate, and assume that there remain much more susceptible than the true number.
He gave a lecture in May 2020. Back then the testing in Israel was very limited. There were about 15,000 cases and 222 death, from that he concluded 1.5% death rate ^. And he insisted there is no need of further testing because we know most of them.
Read 18 tweets
19 Jul
הארגון בנתב"ג הוא חרפה.

בשדה התעופה בחאניה, 3 דקות מרגע הכניסה ועד לגייט.
בישראל - שעתיים וחצי.
אלפי אנשים תקועים בתורות אינסופיים, התור לזה ששואל אם ארזת לבד ונותן מדבקה צהובה, ואז לזו ששואלת אם יש מצ'טה ונותנת מדבקה כתומה. ועכשיו נוספה גם טפסיאדת הקורונה המיותרת.

חלאס! שחררו!
אלו התורים בהלוך בנתב"ג.
אף אחד שם לא עושה כלום. זה רק תורות ל"בטחון" ("ארזת לבד? נתנו לך משהו להעביר? עבר לך בראש פעם לרצוח ראש ממשלה?"), ואז לדלפק בו בודקים כל מיני טפסי קורונה, אחד אחד. איפה ההייטק ניישן? Image
בפעם הקודמת שחזרתי (לפני כחודש) הייתה התקהלות גדולה בתור לבדיקות הקורונה במתחם (הסגור!). אלו היו מסיבות ההדבקה הגדולות של ישראל. אחר כך התפלאו למה הרבה אנשים יוצאים חיוביים שלושה ימים אחר כך, למרות שנבדקו לפני הטיסה ואחריה ונמצאו שליליים
They are measuring their own measures... Image
Read 6 tweets
10 Jul
Israeli MoH telegram channel [1]

bottom left figure (all ages):
%vax in cases very similar to %vax in population while %recovered in cases much lower than in population (835K/9.2M, 9%, but see next) >>

Trans. @RanIsraeli
Look for the file תמצ קורונה

* immunity of recovered is much more stronger, long lasting and robust, than that of vaccination.

* should reduce few cases in unvax group (those unvax & recovered, b/c I compare to unvax & not recovered), thus slightly decrease base rate and VE, but I think it's negligible.
Look at the top right graph.
Does the reason that % of ultra-orthodox people in cases (1%) is much lower than their % in population (about 12%), is the high percent of recovered there?

(officially 30% of them are confirmed cases. The true number can be 50% or more)
Read 5 tweets
8 Jul
Methodology and sources:

upper figure - cases for vax and unvax. The two rightmost columns here…
Then, vax status.
Go here (data pulled from Israeli MoH "dashboard").…
Sum accumulated # 2nd vax number 20 days ago over 20-59 age groups. let's call it A.
Sum pop over 20-59 age groups, let's call it B.
A/B is %vax 2nd dose >= days ago.
Read 22 tweets
30 Jun
Vaccine Efficiency over time in Israel by age groups.

Thanks epidemiologist @prof_shahar for scientific consulting.

Discussion in comments. >>

Israeli government database:…
cases for vax and unvax: אימותים לאחר חיסון
% vax: גילאי המתחסנים Image
Quick recap of vaccine efficiency: Image
The true values of # vax, # unvax are known, hence we have odds(vaccination status).

But # infected&vax, infected&unvax for groups whose all parameters being equal is unknown.
We do have number of confirmed cases in each group. Is it a reliable measurement?
Read 23 tweets

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