At 22:45 30/03/2020, Macfarlane, Alison wrote:
>Firstly, I don't know how this came to appear to be from me, when it 
>was written by Allyson Pollock and I just forwarded it.

I think that was inevitable.  If you forwarded it to the list, the 
list would receive it as "From" you.  Indeed, if it had somehow 
arrived at the listserv "From" Allyson, it would presumably have been 
rejected, unless she is a list member.

>What Allyson's editorial is asking in that people with symptons are 
>ask to report them and then be tested and asked who they were in 
>contact with, unlike the current situation in which people are asked 
>not to report that they are symptomatic unless they become seriously 
>ill. She is pointing out that this could still be done in areas 
>where numbers affected still low.

Oh, I didn't read it like that.  When she talked of "massive case 
finding", I thought she was think of doing this semi-retrospectively 
- i.e. somehow trying to seek out people who were already symptomatic 
- which I think would be of little value (see below - very early 
reporting of the onset of symptoms seems to be crucial).  In terms of 
moving forward, yes, if the government reversed its instruction that 
people should not report the onset of symptoms, and if they were then 
tested immediately (and contacts traced if the test was positive), 
then that's where we should have been all along - and we don't 
(shouldn't) really need the WHO to tell us that!

However, a few further mutterings on the subject of 'testing and 
contact tracing', which may or may not be nonsense ....

As I see it, to be optimally useful, testing and contact tracing has 
to start very soon after the onset of symptoms.  Even then, if one 
believes what we are being told about the timing and duration of the 
'incubation' and 'infectious' periods (of people with 'mild' {and 
presumably also 'asymptomatic} illness), in many cases the 'contact' 
(by whom the 'case' was infected) will have infected all of the 
people they were going to infect, and themselves quite probably 
become 'non-infectious', by the time the person they have infected 
develops symptoms.

The greatest 'hope' is that the 'case' was infected at the very start 
of the contact's infectious period, in which case that contact may 
still be infectious for the first day or two or so of the 'case's 
symptomatic period (and therefore could be isolated for that couple 
of days).  Other than for that (probably not all that common) 
situation, tracing the 'primary contact', per se, would probably not 
achieve very much - so one would have to move on to searching for 
secondary and tertiary contacts, infected 'in parallel' with the case 
we started with (and maybe having by then infected other contacts of 
their own). However, it then becomes a horrendous tracing exercise, 
akin to that done in relation to STDs, and I suspect probably not 
realistic if (moving forwards) there are tens of thousands of cases 
to work from.

I suppose it's much easier now (with the greatly reduced 
'contacting'), but a couple of weeks ago I think that many people 
would have struggled to recall exactly who they had been in contact 
with five or six days previously!

However, that leads to another problem about "now".  With most people 
now 'staying at home' and self-isolating, not meeting family and 
friends etc., most of their contacts, if any, outside of their 
household will presumably be 'unknown strangers' that they have got 
near in shops, or public transport (for those still working) etc. - 
and hence presumably untraceable.

Just a few thoughts - which, as I said, may be nonsense!

Kind Regards,


John

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