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The Maths of Coronavirus

Started by MarkS, Mar 18, 2020, 07:54:54

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Rick

Quote from: The Thing on Mar 31, 2020, 11:13:01Because malaria is a parasite caused disease not a virus or bacteria. Had it in Papua New Guinea when I was working there many many years ago.

Yellow fever is a viral disease transmitted by mosquitos. There's an effective vaccine for it, though, so it's no longer the killer it once was. There are a bunch of other diseases transmitted by infected mosquitos. Some are viral...

Mac

Another interesting read on the BBC from Imperial college.

https://www.bbc.co.uk/news/health-51979654

Mac.


Rick

Quote from: Mac on Apr 02, 2020, 16:43:46
Another interesting read on the BBC from Imperial college.

https://www.bbc.co.uk/news/health-51979654

That's by the BBC's Health correspondent, pulls numbers from all over the place, not just from ICL, and it seems to be trying to make them more confusing rather than less. It's not the first article from him I've seen that has seemed rather wooley.

Rick

The one thing that's certain while the pandemic is still spreading is that the reported figures will be a proportion of the real figures.

The tricky question is "How much below the real figures are the reported figures?".

Even the count of deaths will lag reality because of lag in the reporting system, so that "died today" headline figure is really a "deaths reported today" one, and with the cases still on the rise that will inevitably be lower than reality.

An "admitted to hospital" figure might do a bit better, but even that's going to be skewed by decisions on whether to take a patient to hospital or not, and that's going to be affected by how busy the hospitals appear to be.

There's no chance of doing more than guessing how many people have the infection in the population at large until decent samples of cross-sections of the population can be tested. Even then, the accuracy (or lack of it) in the tests will also skew things.

NoelC

Mac - an interesting article but somewhat confusing in it's conclusions.
Rick - Groinuad article: I agree with most of his comments - very poor performance by Boris, and almost certainly career limiting.

It appears to me that there is no clear strategy from the Government, far from being lead by the science they are being chased by it!  What was clear from the outset I feel was that containment and aggressive contact tracing was the only solution until vaccine's could become an option (if they ever do - we are still waiting for one for HIV). The Chinese had 1800 teams working on contact tracing.  For that reason testing is the only solution to lockdown (as lockdown arguably will cause more damage than COVID-19).

On your point about case figure reliability; here is an interesting analysis based on Case Fatality Ratios (CFR):-
https://cmmid.github.io/topics/covid19/severity/global_cfr_estimates.html
The pertinent point is the table half way down which puts our case figure reliability at 5% (i.e. the error is 95%).  The US are late to the party (as usual) but are ramping testing at an astounding rate (17% and rising) - something we should learn from.

There is a danger that as countries get this under control; they will  keep borders closed to countries that have inadequate controls, with consequent effects to economic recovery.

Concerning as this all is; spare a thought for those in sub-saharan Africa and South America with no medical support.  We needed to halt this sooner for their sake.  If they had adopted this approach to Ebola we'd be blaming them for the consequences.
Swapped telescopes for armchair.

Rick

I have family in sub-Saharan Africa. At the moment most of them are on a relatively remote ranch, but sooner or later they'll come into contact with the virus. The bigger effect at present is the complete cessation of the tourist trade. That's usually a huge earner for Kenya, not just in tour companies and hotels, but in small market traders and all the rest, and a lot of people are already, just a fortnight in, near enough destitute as a result of the sudden complete lack of income. If the virus gets hold, I expect the death rate to be somewhat higher than it is here, because there in't the medical care. The effect on the country will not be pretty. :(

ApophisAstros

i am not sure about other people but in our whole extended family spread out over the whole south east we have only heard of 1 confirmed case 58yrs (survived) and a 4 year old child slight symptoms.
Is this similar to other peoples experience so far ?
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Carole

Quotejust a fortnight in, near enough destitute as a result of the sudden complete lack of income. If the virus gets hold, I expect the death rate to be somewhat higher than it is here, because there in't the medical care. The effect on the country will not be pretty. :(
That's extremely sad to hear.

Quotei am not sure about other people but in our whole extended family spread out over the whole south east we have only heard of 1 confirmed case 58yrs (survived) and a 4 year old child slight symptoms.
Is this similar to other peoples experience so far ?
My niece's husband has had it and got over it.

My uncle (aged 90) died of pneumonia just as this whole thing was starting in the UK,  but I don't think it was CV related.  However by the time of his funeral only 5 were allowed to go.

I think I have heard of another non related person who has had it.

If you check in your area, you will find There are 216 confirmed cases in West Sussex, out of a local population of 858,852  (I didn't know your postcode)

There are 434 confirmed cases in Bromley, out of a local population of 331,096

https://www.bbc.co.uk/news/uk-51768274


ApophisAstros


If you check in your area, you will find There are 216 confirmed cases in West Sussex, out of a local population of 858,852  (I didn't know your postcode)

There are 434 confirmed cases in Bromley, out of a local population of 331,096

https://www.bbc.co.uk/news/uk-51768274
[/quote]
The map lower down is very interesting , it seems that the very high cases seem to be clustered around the cities near to major airports London , Liverpool ,Manchester , Newcastle ie the HUBS.
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Rick

Quote from: Apophis on Apr 05, 2020, 13:42:58Is this similar to other peoples experience so far ?

I'm certain that in the UK at least, the "confirmed cases" figure is a small fraction of those actually infected. We'll know more if the testing becomes more widespread.

Two of my friends, who live in Eltham and work in central London, have had an unusual illness. One had a cough that felt like "a nest of wasps in my chest" and the other just felt a little low and lost her sense of taste and smell for a while. (The second would have caught it from the first, and though they've not been tested, I'd guess they've probably had CV-19.) Another friend got to work (in London) earlier in the week to hear that a young colleague had just died of CV-19 complications, and a young friend who's an ambulance paramedic (in South-East London) said that everyone he's sent to is dying, by which I think he means he's probably had at least one of them die in the ambulance, and he doesn't think the survival chances of the others are particularly good.

Over in the US, a couple of my friends just reported that one of their social circle, who'd been recovering from complicated surgery, died yesterday. They said that "COVID-19 was the one thing too many for him".

Rick

Some relatively raw data from ICNARC (Intensive Care National Audit & Research Centre) on recent COVID-19-related deaths in the U.K.

https://www.icnarc.org/DataServices/Attachments/Download/76a7364b-4b76-ea11-9124-00505601089b

Plenty of tables and graphs. A couple of the the things I noticed were:

1) that over 90% of patients who died were "Able to live without assistance in daily activities" before falling ill, and only about 7% had other severe "comorbidities". That suggests that the "would have died soon anyway" line being pushed elsewhere is a load of fetid dingoes kidneys (thanks, Douglas Adams, for that phrase).

2) Roughly two thirds of those who died were men.

Rick

Oh, and about half of those entering critical care end up dead.

ApophisAstros

Hope Boris isnt one of them,
Roger
RedCat51,QHYCCD183,Atik460EX,EQ6-R.Tri-Band OSC,BaaderSII1,25" 4.5nm,Ha3.5nm,Oiii3.5nm.

Hugh

Some good information from a couple of medics this morning on TV.  A Consultant giving a realistic report on the potential ways forward after infection.  He emphasised that this is not flu and the early reports that it is a worse form of that are totally wrong ~ this is something completely different.  Comparison with other countries with high mortality is difficult as differing health impactors, especially the rate of smoking, is important. 

One speaker indicated that the initial viral load is all important.  A casual interaction giving a small viral load enables the body to deal with the virus more effectively whereas a number of collective interactions are more likely to lead to a worsening later on ~ perhaps as per the PM?  Perhaps also as other countries, Italy for instance, where families live together.  It does seem that if you are not seeming to clear the symptoms over 7-10 days, then however you feel, you should be getting yourself introduced to the health system as it may be more likely to worsen quickly.

I've seen several interesting reports recently about the efficacy of breathing exercises ~ some from doctors via social media ~ which I'm probably going to start.  They revolve around deep breathing exercises lasting a few minutes ~ the couple named Abel, who featured quite early on on TV reporting from the cruise ship and who ended up in hospital as positive ~ have also reported via social media on recovery that they had used them and it had helped.  Part of the exercises require you laying on your front as this opens up the airways more effectively.  Laying on your front is also a position that is used in hospitals as treatment when hospitalised.

If anyone is interested, text/Whatsapp me and I'll forward for you.

Keep well my friends and and wash your hands!

Hugh