Thread by @petermbenglish

Following on my marathon thread on testing ( threadreaderapp.com/thread/1308088… ), some thoughts on the app, which is due to be launched this week.
1/9

Most people with Covid-19 will never be identified.

Most never have symptoms. Few will be tested, and the test misses 70% of sick people, and even more of those without symptoms.
2/9

Which means, the app will only ever identify a fraction of people with Covid-19.

So not having been alerted that you've been in contact with somebody who might be infectious won't mean you haven't been.

So…
3/9

-Self-isolate if you’re sick (but be aware most people with Covid-19 have not symptoms)
-Keep contact with other people to a minimum. Don’t meet with 6 people if you can avoid it!
4/9

-If you risk being within 2m of another person (not in your household the people you share accommodation with*) wear a mask. If you want to wear a visor for eye protection, fair enough; but the mask matters more.
5/9

-If you are vulnerable – prior condition or shielding – be even more cautious. If you can’t avoid mixing with people outside your household, wear an FFP2 mask.
6/9

-Keep up the handwashing, especially if you have to touch eg door handles touched by many other people – and carry alchohol-based hand gel to use if you can’t wash your hands (eg when you’ve had to pull a toilet door open after washing your hands).
7/9

Testing is useful for knowing where in the population the disease is; but as most people don’t get symptoms, it won’t prevent you from mixing with infected people, or with susceptible people if you’re infected.
8/9

Similarly, only a fraction of cases will ever be identified, so many of them won’t show up on any app. Contact tracing helps; but the points above are far more important.
9/9

Oops postscript:

The twitter thread linked to in the first tweet in this thread was a brilliant thread by @izzybraithwaite - but not the thread I'd intended to link to, which is:
or threadreaderapp.com/thread/1306859…