７７％まで低下したコロナワクチンの「死亡防ぐ効果」の意味

 Public Health England yesterday released their latest technical briefing on the variants of concern, number 20, and it has some illuminating data.

It provides us with the infection, hospitalisation and death rates for the Delta variant, broken down by vaccination status and age. This allows us to do a calculation of the real-world vaccine effectiveness in the over-50s during the Delta surge, albeit a rough one without any adjustments.

The latest report has data up to August 2nd. If we substract from these values the data in Briefing 17 (up to June 21st) then we get the data covering the period June 22nd to August 2nd, which broadly corresponds to the bulk of the Delta surge in the U.K. The vaccine rollout to the over-50s was basically complete by this point, having stabilised according to PHE at around 88% double vaccinated and 10% unvaccinated (the other two per cent remaining single vaccinated, perhaps due to a bad reaction to the first dose).

In this period the PHE data tells us there were 2,464 Delta cases in the unvaccinated over-50s and 17,926 in the fully vaccinated over-50s. From this we can estimate the vaccine effectiveness against infection in the over-50s during the Delta surge as 17% (1-[(17,926/88%)/(2,464/10%)]). This confirms using additional data the estimate I made last week.

We can make a similarly rough calculation of the vaccine effectiveness against death. Between June 22nd and August 2nd, PHE reports that among the over-50s there were 339 deaths with the Delta variant in the double vaccinated and 167 in the unvaccinated. Using the same proportions vaccinated and unvaccinated as above, this gives a vaccine effectiveness against death in the over-50s during the Delta surge of 77% (1-[(339/88%)/(167/10%)]). Interestingly, this is very similar to the latest estimate of vaccine effectiveness against serious disease from Israel, which is around 80%. This is a decent level of protection and helps explain why the Delta surge had proportionally fewer hospitalisations and deaths, but it is well below the levels suggested by earlier studies and quoted by PHE, which are north of 95%.

https://dailysceptic.org/2021/08/06/devastating-new-data-from-phe-shows-vaccine-effectiveness-down-to-17-and-no-reduction-in-infectiousness-but-mortality-cut-by-77/

仮にコロナワクチン接種が死亡防ぐ効果が100%だとしたら本来は・・・

未接種　506 (339+167)

接種済　0

死亡の全員が未接種のはず。

 仮にワクチンの死亡に対する有効性が０％だとした場合、接種率は88％ですから・・・

未接種　６１

接種済　４４５（５０６X８８％）

となる。

理想は有効性１００％、即ち５０６/０で完全にダメダメ（有効性ゼロの失敗作）が６１/４４５。

実際は７７％すなわち１６７/３３９。

有効性７７％という数字を聞くと普通の統計学なんぞと無縁の人は重症を抑え込む効果が７７％だとして結構優秀だと思い込むが、実際は重症を抑え込む効果１００％（５０６/０））とは程遠いどちらかというと完全にダメダメの重症を抑え込む効果０％の（６１/４４５）に近い数字。

これが薬品会社の常とう手段、数字のトリックなんですよ。

要するに死亡を防ぐという面でワクチンの売り文句は悪質な誇大広告。（爆ｗｗｗｗｗｗ

例えば・・・

コロナワクチン接種、死亡防ぐ効果99% イスラエル - 朝日新聞 ...

https://www.asahi.com › articles

2021/02/21 — イスラエル保健省は20日、ファイザー製ワクチンを2回接種して2週間が経った場合、未接種の場合と比べ、死亡に至ることを防ぐ効果が約99%だったと発表 ...

　イスラエル保健省は20日、ファイザー製ワクチンを2回接種して2週間が経った場合、未接種の場合と比べ、死亡に至ることを防ぐ効果が約99%だったと発表した。重症化や感染についても95%を超える高い予防効果がみられたという。

　保健省は2月13日までに得られたデータを分析。2回目のワクチン接種から1週間後と、2週間後の効果を検証した。その結果、2回目の接種から2週間後には、死亡に至ることを防ぐ効果は98・9%▽重症化を防ぐ効果は99・2%▽入院を防ぐ効果は98・9%▽感染を防ぐ効果は95・8%――だったという。1週間後では効果がやや低く、死亡を防ぐ効果は94・5%▽重症化を防ぐ効果は96・4%▽入院を防ぐ効果は95・6%▽感染を防ぐ効果は91・9%――だった。

https://www.asahi.com/articles/ASP2P3QKGP2PUHBI007.html

、、、（爆ｗｗｗｗｗｗｗｗｗｗｗｗｗ