[SA Chris]

Seen this article crop up a few times.

https://elemental.medium.com/coronavirus-may-be-a-blood-vessel-disease-which-explains-everything-2c4032481ab2

Interesting theory for sure.

[Paul B]

When was the last time lives were worth a million quid on average? Especially old/sick ones. The NHS cost effectiveness threshold is something like £20k per QALY. Cant see how the covid cost isn't quite handsomely north of that.

Guidance in my industry allows for you to essentially put a price on loss of life when comparing it to the cost of remedial works. That figure is considerably in excess of £20k and it's far nearer the million quid.

Imagine for instance you've done a load of works to make something safe in 2018 to current best practice as the loss of life as a result of failure is likely. You spend £Xm. In 2020 if that guidance is updated and the difference between the 2018 condition and the current isn't 'that much' (in terms of loss of life) but will cost £££ to improve to the modern standard it's considered disproportionate. However, as above, those figures aren't ~£20k/head.

I've had cause to review something as to whether it's proportionate today and the figure used is £1.7M per loss of life. Furthermore, for something to be considered disproportionate it needs to cost somewhere between 2-10 times that figure (depending on the certainty of the cost-estimates used).

Some light reading if anyone's inclined:
https://www.hse.gov.uk/risk/theory/index.htm

[seankenny]

I see patients recovering from the worst stages of it at work, and frankly given the state of many of them a couple of months down the line, I think that people need to get a lot more scared. You might get a mild case, or, you might get death or several months of agony and struggling to find the energy to stand up.

I hear this time and again. Speaking to a friend on the weekend, she said she probably contracted it  at a conference before lockdown, from sitting next to someone a few hours who had it (so moderate load she thought) and she was in bed for a week, and is only now feeling like she can do any running at all, and that is still very slow and very short distances. She reasonably fit and healthy and in early 40s.

I'm still feeling the effects of the virus on my lungs a couple of months after having been ill with it. I'm a crap runner at the best of times but it's now noticeably harder than before and I'm a fair bit slower.

I understand why younger people are generally blase about it, even though I think they could be a bit irresponsible, but I don't get why anyone over 40 would be relaxed about covid.

[Oldmanmatt]

I see patients recovering from the worst stages of it at work, and frankly given the state of many of them a couple of months down the line, I think that people need to get a lot more scared. You might get a mild case, or, you might get death or several months of agony and struggling to find the energy to stand up.

In addition to the brutally long recovery for people who've been hospitalized, especially people who've been on ventilators etc., there also seems to be a phenomenon where some people get fairly mild cases but very prolonged post-viral symptoms:

https://www.theguardian.com/world/2020/may/15/weird-hell-professor-advent-calendar-covid-19-symptoms-paul-garner

This is a weird fucking virus.

Possibly even weirder than that Slabs:

https://time.com/5848949/covid-19-asymptomatic-spread/?utm_source=facebook&utm_medium=social&utm_campaign=editorial&utm_term=health_covid-19&linkId=90213795

Interesting read and the “asymptotic but showing significant lung damage” thing is quite scary. If it turns out that these numbers are correct, we’re looking at some unpleasant long term issues.

[tomtom]

Had a test yesterday. The COVID app sent me an email saying go get a test (despite having no symptoms) as they wanted to test people who may not have it as well.

Anyway / 7pm I booked a test (took 2 min) for 7:30. Left at 7:10 and was home at 7:35. 3 out of 12 ‘bays’ at the test centre were open and there was a que of 1-2 cars per bay. The throat swab was easy (no gag) but he had a good root up my nose which made me sneeze!

See when I get a result.

[tomtom]

Local track and trace in Ceredigion seems to have paid off:

https://www.walesonline.co.uk/news/wales-news/area-wales-missed-coronavirus-simple-18348215?utm_source=facebook.com&utm_medium=social&utm_campaign=sharebarfp2isAT-_qp8oVJ0NP4v8Nt4X0EYTr6iH-o

[tomtom]

Had a test yesterday. The COVID app sent me an email saying go get a test (despite having no symptoms) as they wanted to test people who may not have it as well.

Anyway / 7pm I booked a test (took 2 min) for 7:30. Left at 7:10 and was home at 7:35. 3 out of 12 ‘bays’ at the test centre were open and there was a que of 1-2 cars per bay. The throat swab was easy (no gag) but he had a good root up my nose which made me sneeze!

See when I get a result.

Result took 27 hours. Negative unsurprisingly. I’d encourage anyone to get themselves done if they are concerned. If you can get to a drive thru there is clearly capacity and it wasn’t painful.

[largeruk]

Embarrassingly I don't know this and can't find a definitive answer. Anyone know the length of validity of a negative test, ie. does a negative test mean you don't have COVID on that day but a test taken the next day might show as positive?

[tomtom]

Embarrassingly I don't know this and can't find a definitive answer. Anyone know the length of validity of a negative test, ie. does a negative test mean you don't have COVID on that day but a test taken the next day might show as positive?

^^ yes. Its only negative for the time the swab was taken.

[Offwidth]

The lack of knowledge on this is partly down to another failure of PHE.

https://www.theguardian.com/world/2020/may/25/doctors-condemn-secrecy-over-false-negative-covid-19-tests

[largeruk]

Embarrassingly I don't know this and can't find a definitive answer. Anyone know the length of validity of a negative test, ie. does a negative test mean you don't have COVID on that day but a test taken the next day might show as positive?

^^ yes. Its only negative for the time the swab was taken.

Thank you. That prompts 2 further questions. Given the above:-
1. are those admitted to hospital with covid symptoms tested on a daily basis and not just upon admission to take account of the short validity period of a negative test?
2. what is the current assessment of the incubation period before the onset of symptoms during which you are infectious but don't know you are?

[tomtom]

For 2 - I think on average it’s 5 days from infection to symptoms... to take a stab at a couple of days before that...

Which means for 1.  Really you should be testing everyone every 2-3 days at least in an important setting. Iirc that’s what makes it so much harder to stop than Mers or sars - where symptoms would appear at same time you were infectious (I think)

[Oldmanmatt]

Embarrassingly I don't know this and can't find a definitive answer. Anyone know the length of validity of a negative test, ie. does a negative test mean you don't have COVID on that day but a test taken the next day might show as positive?

^^ yes. Its only negative for the time the swab was taken.

Thank you. That prompts 2 further questions. Given the above:-
1. are those admitted to hospital with covid symptoms tested on a daily basis and not just upon admission to take account of the short validity period of a negative test?
2. what is the current assessment of the incubation period before the onset of symptoms during which you are infectious but don't know you are?

Pretty sure, once symptomatic, you test positive, barring a faulty test.

What it won’t tell you, is if you have had it and are now virus free (which, apparently, doesn’t mean symptom free, as the damage can leave you with symptoms that outlast the infection).

[largeruk]

I think on average it’s 5 days from infection to symptoms... to take a stab at a couple of days before that...

I'm a little confused. So roughly 5 days incubation period (infection to onset of symptoms). What did you mean by the words in bold? Sorry for asking, my brain is also clearly on lockdown...

[colin8ll]

Anyone know the length of validity of a negative test, ie. does a negative test mean you don't have COVID on that day but a test taken the next day might show as positive?

More or Less on R4 covered this topic recently (although not your specific question). Their expert guest said false negative test results are around 30% (or was it 40%?) and argued that any symptomatic person should be self isolating regardless of test results

[tomtom]

Isn’t there quite a lot of research showing that people have the virus and are shedding/capable of passing it on a couple of days before they become symptomatic (timings approximate as there seems to be no hard or fast rule..)

[Sidehaas]

Isn’t there quite a lot of research showing that people have the virus and are shedding/capable of passing it on a couple of days before they become symptomatic (timings approximate as there seems to be no hard or fast rule..)

I believe that's true. In fact I've seen various articles saying it may be the most infectious period. As I understand it from the medical experts at the daily briefings, it's also the case that in that period (when highly infectious) you are likely to test negative. This is the reason for not providing tests to those who are isolating as contacts of an infected person.
I've seen numbers ranging from very low up to 40% for false negatives. A colleague whose wife is a doctor with a relevant specialism and who had to be tested recently told me that it was known to be even higher than that if you don't have both nose and throat swabs - the point of having two at the same time is to reduce false negatives and apparently the approach to giving one or both is (or was) inconsistent. My wife had a home test (negative) that came with both.
I'm not sure whether the higher % numbers you see for false negatives are just for the period in which people are actually symptomatic or whether they include pre symptomatics and asymptomatics as well. I'd guess it's probably an average over the lot, in which case you'd think the number of false negatives for people who are actually symptomatic would be lower(?)

[galpinos]

Pretty sure, once symptomatic, you test positive, barring a faulty test.

Nope, you can still test negative with symptoms

What it won’t tell you, is if you have had it and are now virus free (which, apparently, doesn’t mean symptom free, as the damage can leave you with symptoms that outlast the infection).

One of my wife's hospital's is antibody testing all staff. Total random mix of who seems to have had it and those that haven't, pretty poor correlation with those who had symptoms.

[galpinos]

Isn’t there quite a lot of research showing that people have the virus and are shedding/capable of passing it on a couple of days before they become symptomatic (timings approximate as there seems to be no hard or fast rule..)

There is, but you are a lot more effective at spreading with symptoms, i.e. coughing is a better mechanism to spread than just breathing.

[nik at work]

“My experience is the test seems to be about 70% accurate 6-8 days after initial infection/exposure, either side of that the reliability tails of dramatically”
My neighbour (infectious disease consultant)

“Yeah, we’re seeing pretty much the same”
My other neighbour (respiratory consultant)

Testing is useful no doubt, but given it’s fairly limited reliability I’d say a fairly aggressive self isolation policy and a lot of focus on the track and the trace element of Test Track and Trace would be most effective... which isn’t happening afaik??

A negative test is certainly not by any measure the “all clear”.

[tomtom]

I may have posted it here or on the politics thread - but Ceredigion councils home baker track and trace recognised the importance of starting the TTI when people were first symptomatic - not when the result came back. Thus saving/buying an extra 24-48 hours for each case. If the test is 70% accurate then the only real way is to keep on repeating the testing... and repeat and repeat.

[nik at work]

Exactly. Isolate and trace contacts ASAP, don’t worry about waiting for test results. And don’t put much stock in a negative result. Use the tests as confirmatory only.

[gme]

https://www.cnbc.com/2020/06/08/asymptomatic-coronavirus-patients-arent-spreading-new-infections-who-says.html

[SA Chris]

I like the "who says" at the end of the link.

[Oldmanmatt]

https://www.cnbc.com/2020/06/08/asymptomatic-coronavirus-patients-arent-spreading-new-infections-who-says.html

Promising.
There’s a fair amount of hopeful news around. I forgot to share it (busy, this is my tea break) but earlier I read that Bergamo has around a 50% exposure to the virus, according to some comprehensive antibody testing done there. I understood that meant there had been significantly more asymptotic cases than originally thought. That tied in with the US carrier Rosy Roads, where they discovered around 60% of the crew had antibodies. Way more than expected.
Glimmers.