So in summary, the app has similar accuracy to manual recall of contacts, but is reaching more contacts per person. Of course, manual tracing has broader reach: both approaches have pros and cons, you need both; but it’s useful to see them side by side. 6/n pic.twitter.com/FNnNgxkpQf

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

During that time period, 560,000 app users tested positive for COVID. This resulted in 1.7 million app users being contact-traced by the app. At an individual level, 4.4 contacts were notified per positive user who consented to have their contacts traced (‘sharing keys’). 3/n pic.twitter.com/d0N6B882aC

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

Very interesting. But implication for public health and public policy: perhaps mandate usage? Political hot button. But seems reasonable in a crisis, no? https://t.co/NZi6STDtYs

— Kenneth Cukier (@kncukier) May 12, 2021

We used the number of exposure notifications, the secondary attack rate, and the adherence to self-isolation to model the projected number of cases averted from Oct to Dec. This came out as 284,000 (108,000-450,000) cases averted, over a baseline of 1.89 million. 7/n

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

Now peer-reviewed in Nature, “The Epidemiological impact of the NHS COVID-19 App”. Here’s a quick rundown of results & what they mean. We estimated that the app prevented several hundred thousand cases from arising. The app works. https://t.co/aR5UpbI5dm 1/n pic.twitter.com/Cs8xsuYDxT

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

Brilliant work by @ChrisWymant @LucaFerrettiEvo @ChristoPhraser and colleagues.

A pandemic in 2020 should not be dealt with using only decades old tools.

This is a crucial advance and important evidence base to continue accelerating unconventional tools to combat transmission https://t.co/Afen41E9fX

— Michael Mina (@michaelmina_lab) May 13, 2021

Using this approach, we estimated that the app averted 594,000 cases out of 1.89 million cases that actually took place. In other words, contact tracing with the app reduced the second wave of COVID by a quarter. 14/n

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

Very cool – the NHS Covid app may have prevented 284,000–594,000 cases, meaning 4,200–8,700 fewer deaths.

A lot of people confidently asserted that this was a waste of time and money – hope they'll explain what their views are in light of this. https://t.co/aSHpWlc4bM

— Sam Bowman (@s8mb) May 14, 2021

Good evidence that exposure notification apps have saved lives, at far lower adoption rates than critics feared was necessary.

I continue to think this was an example of great tech & great privacy design making the right bet. Not everything is awful.
https://t.co/ZXMadcGYAS

— Ben Adida (@benadida) May 13, 2021

We evaluated the app during the three months after its launch in England & Wales, Oct through December 2020. During this time, the app was actively used by 16.5 million people, 28% of the total population (map a users, map b, cases). 2/n pic.twitter.com/pZB1t4niEm

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

Great to see BBC recognition of the positive impact of NHS tracing app in reducing second wave infections by 600,000 and saving tens of thousands of lives @ChristoPhraser @bdi_oxford @NHSX https://t.co/oGHSd2PUbr

— Nicole Mather (@NicoleMatherLS) May 13, 2021

New study estimates that the NHS Covid-19 app reduced the size of the 2nd wave by around 25%. Surely this will encourage ministers to push its use as we emerge further out of lockdown. https://t.co/S6AIsfcwIc

— Hugo Gye (@HugoGye) May 13, 2021

The epi relevance of a #covid19 contact tracing app is clear. Every % of adoption ⬆️ is relevant. Continued development and population buy-in should be a national priority.

Do we need a re-launch without the mandatory nonsense but rather the addition of incentives? #ostanizdrav https://t.co/8SivIM1WHR

— Dr. MF (@pucciami) May 12, 2021

Out in Nature today: The effect of the NHS Covid-19 app. Secondary attack rate 6%, 300K-600K estimated cases averted in 3 months, every additional percent app use reduces cases by 0.8%-2.3%.

Brilliant work by @LucaFerrettiEvo @ChristoPhraser et al. https://t.co/JP3GlE8395 pic.twitter.com/fWcDTlloAy

— Marcel Salathé (@marcelsalathe) May 12, 2021

Now peer-reviewed in Nature, “The Epidemiological impact of the NHS COVID-19 App”. Here’s a quick rundown of results & what they mean. We estimated that the app prevented several hundred thousand cases from arising. The app works. https://t.co/aR5UpbI5dm 1/n pic.twitter.com/Cs8xsuYDxT

— Christophe Fraser ? (@ChristoPhraser) May 12, 2021

イギリスの国民保健サービス(NHS)の新型コロナウイルス接触追跡アプリ「NHS COVID-19 app」https://t.co/Z4ydCfj3dN
は、数十万のコロナ症例と数千の死亡を予防と研究者たちは予測。
このアプリは9月リリース以来、1650万人が定期的に使用。
ネイチャー掲載論文は
これhttps://t.co/yJkgnbFRxt

— 笹山登生 (@keyaki1117) May 13, 2021

⁦.@NHSX⁩ did the right thing to pursue the ⁦@NHSCOVID19app⁩. It’s now clear ⁦@MattHancock⁩ and ⁦@matthewsgould⁩ were right. Technology can play a very important role in delivering public services https://t.co/OGE3k9RmkO

— Daniel Korski (@DanielKorski) May 14, 2021

Apple and Google’s smartphone/bluetooth contact tracing system, as deployed by the NHS, saved 4-8k lives in the UK. https://t.co/VgZf0k4C4V

— Benedict Evans (@benedictevans) May 14, 2021

英国で日本のCOCOAと同様の接触者確認即時通知アプリが効果あったとNature誌から。

英国はNHSアプリ（10-12月、英国民28％、約1650万人）使用で30～60万人の新規感染回避したと推定。ユーザー数が1％増えるごとに、感染者0.8％(モデリング)or2.3％(統計分析)減少した。https://t.co/Vq6EYygKYu pic.twitter.com/mT4X6FSUC2

— Hiroshi Tsuji (@Hiroshi_Tsuji) May 13, 2021

イギリス政府版ココアは数十万件の感染を防いだという分析

The epidemiological impact of the NHS COVID-19 App
Chris Wymant, Luca Ferretti, Christophe Fraser, et al. Nature (2021)https://t.co/1DysCDyzX5 https://t.co/U63X0AB21Z

— けんもう新型コロナ対策本部 (@kenmomd) May 13, 2021

RELEASED: The Epidemiological Impact of the NHS #COVID19 App

? Analysis suggests digital contact tracing averted several hundred thousand cases

Read More: https://t.co/Oaj1johoYT

[Authors linked below] #100daysofcode #DataScience #PublicHealth pic.twitter.com/zbLCSmS5gH

— Alvin (@alvie_barr) May 12, 2021

The epidemiological impact of the NHS COVID-19 App. A mobile phone app records proximity events between app users, and when a user tests positive for COVID-19, their recent contacts can be notified instantly.#pandemic #contacttracing https://t.co/fHhM7AJPkQ

— SmartFlight (@SmartFlightInfo) May 13, 2021