Coronavirus testing

Wed 29 Apr 2020, 19:55 (last edited on Wed 29 Apr 2020, 20:03)

Steve, cannot disagree about reading too much into the App data for the reason you suggest, although there are currently 2.75 million people taking part  - it is the App developed by Kings College in conjunction with Guys and St. Thomas’ 

Wed 29 Apr 2020, 18:25 (last edited on Wed 29 Apr 2020, 18:53)

The reason why care home staff are being tested even though asymptomatic is that it has been demonstrated that people can be infectious before they develop symptoms, or even if they never develop symptoms at all. It is this feature of COVID-19 that makes it particularly tricky.

This means the test could pick up people who are infectious who are without symptoms. Clearly this can apply to anybody in the community, but it's particularly important to identify such individuals when they are care or health workers as they are dealing with vulnerable people face-to-face. With limited testing capacity, it's a matter of priorities.

nb. I would be a little careful of reading too much into the WODC estimates based on an app as it's going to have a self-selection bias. It's not a substitute for a properly designed representative population sample.

Wed 29 Apr 2020, 17:05

Hancock said yesterday that asymptomatic staff and residents in Care Homes would also be able to be tested, as well as NHS and front-line health staff, with or without symptoms. This is rather puzzling if the test only works for those with symptoms. 

But as for over 65s in general, it's clear that it is only for those with symptoms. 

Wed 29 Apr 2020, 16:39 (last edited on Wed 29 Apr 2020, 17:12)

Yes, Steve is correct in that the test is only for people over 65 in the general public with symptoms, it isn’t a general extension for everyone over 65. As Christine points out above, those in Care Homes can be tested whether or not showing symptoms.

There is a respected Covid-19 App that is collecting data from the wider population (whether symptomatic or healthy) where you log your health each day.

As of yesterday there were 3476 people in WODC taking part and the data projects that 0.8% of the population in WODC are currently symtomatic.

Wed 29 Apr 2020, 13:16 (last edited on Wed 29 Apr 2020, 13:17)

I think that you have to be both over 65 and symptomatic to be eligible. The capacity of 100,000 tests a day by the end of April would still only allow about 0.15% of the population to be tested on any one day. Even if it was confined to just NHS and Care workers, then it would take three weeks to test them all.

As far as testing for the spread of the infection is concerned, then serological tests (that is tests for antibodies) might be more useful as the live virus test only works for that window of a few days when you are infected. So far, the serological tests haven't yet been found reliable enough to tell whether you've gained immunity. In the first instance, those are likely to be used by epidemiologists, but if they do that properly it's important it's done using a controlled, representative sample as self-selecting groups produce misleading results.

Wed 29 Apr 2020, 13:01

I wonder if any of you clever people can help with some input?

I read this morning that testing had been extended to all those over 65.  So I went on to the Government website and registered for a self test kit.  I went through the whole process, which wasn't arduous, only to be told that I wasn't eligible.

I'm not unduly concerned but it would be nice to know, if only to inform the "powers that be"!  I understand that the data is used to track the extent of the infection.  Also, I suppose that it will be helpful when we start to "track and trace".