Contact tracing, a rant

[BushInn1746]

UK Health Minister explaining the IoW Test, Track & Trace Pilot Scheme now on BBC 1.

Does not mean an end to Social Distancing and Stay at Home for the moment.

[ThrelfallYorky]

I don't think I'm really a technophobe, I had a mobile 'phone in the 1990s, an analogue one, so far back, and I happily use a p.c., and a laptop, and a tablet, and quite a lot of complex software, but I've never felt the need to get a smart phone myself.
I used to have my mobile on contract, but now it's a simple PAYG on, as I use one only for making and receiving calls, occasional texts, I don't even use my current one's camera, as I always have a decent camera in my bag or pocket, have carried one even since pre- digital days.
I have nothing against "them" knowing where I am, or who I have just lingered with, but have no intention of replacing what I've got with a smart phone. OH has a natty smartphone, but the number of times he leaves it at home, or in his car, or the battery is down, makes me suspect he'll be as useless as me to the statistics, but for different reasons!
The theory sounds great, but I suspect it'll not work well enough to be deeply useful.

[groom]

Having to have your bluetooth on at all times also reduces the practicality of the app as it drains batteries faster so the phone wouldn't remain on long enough for someone to work a whole shift at work.

According to Matt Hancock, the App has been designed not to drain your battery. I presume this is one of the reasons they are trialling it before it goes nationwide in a few weeks.

[pharmaT]

Having to have your bluetooth on at all times also reduces the practicality of the app as it drains batteries faster so the phone wouldn't remain on long enough for someone to work a whole shift at work.

According to Matt Hancock, the App has been designed not to drain your battery. I presume this is one of the reasons they are trialling it before it goes nationwide in a few weeks.

The app itself perhaps but just having my bluetooth switched on drains my battery.

[avm228]

According to the press conference, the relatively low level of smartphone use among residents of the Isle of Wight (due to demographics) is one of its attractions as a trial site for the app - in that if it achieves its objectives in a low-smartphone community it’ll work anywhere.

[Guy Etchells]

Having to have your bluetooth on at all times also reduces the practicality of the app as it drains batteries faster so the phone wouldn't remain on long enough for someone to work a whole shift at work.

According to Matt Hancock, the App has been designed not to drain your battery. I presume this is one of the reasons they are trialling it before it goes nationwide in a few weeks.

The app itself perhaps but just having my bluetooth switched on drains my battery.

The bluetooth portion of the app is specially developed to have low power requirements so it does not run down your battery.
If you think about it they do not want the bluetooth to have a powerful signal as that would be able to connect over a large radius, they only want a very limited range for these purposes.
Cheers
Guy

[Ruskie]

15 minutes  :,  that makes a complete mockery of social distancing outdoors, where, we have been told, a mere casual 10 seconds as someone passes by is sufficient.

I am mystified, I do wonder if governments are clutching at straws, guided by their advisers, none of whom seem to agree.

Can I have a bottle of Madagascan juice please, it’s likely as useful as anything else.

Mike

It is probably a steep learning curve for everyone including governments, their advisors, health professionals, so not surprising there are mixed messages .... however they say that using a tracing app is how China managed to get back to normality relatively quickly - similarly with Singapore (there are probably other countries who are also using this technology).

[arthurk]

One of the things that concerns me a bit about this app is the proportion of people who develop symptoms, get tested, and are then found not to have the virus.

I've only done a quick search, and the first figures I found were those published today for Scotland. These show that to date (5 May), NHS labs in Scotland have tested 63,311 people, of whom 50,874 were confirmed negative and were 12,437 positive. These can be found at https://www.gov.scot/publications/coronavirus-covid-19-daily-data-for-scotland/ - though it looks as though the page is updated every day.

In very round numbers, it appears that about 80% of those tested will not have the virus, and if the same is true when the app is rolled out, then unless I'm mistaken, the following will happen:

Someone has symptoms and notifies the app. All their contacts are told of this and have to self-isolate. But there's only an 1 in 5 chance that the first person actually has the virus, so 5 times as many people will be in 14 days' full isolation as need to be - and since they will probably have had to do this at short notice, they might not be able to arrange food deliveries etc. (And this assumes that the app is reporting contacts accurately; if it's too sensitive or picks up people the other side of walls, the numbers affected by this will be immense.)

Please can someone explain whether this has been properly thought through? Or have I missed something?

[Mike in Cumbria]

One of the things that concerns me a bit about this app is the proportion of people who develop symptoms, get tested, and are then found not to have the virus.
….
Please can someone explain whether this has been properly thought through? Or have I missed something?

Your contact data is only sent out when you have been diagnosed with COVID19, not when you have symptoms.