It can't have been spreading exponentially from a significantly earlier time. If there were much earlier cases, either they just luckily didn't spread at all (eg just a handful of cases coming from an animal source) or else it was a slightly different strain that was much less contagious.
Things don’t just get switched on. It is possible that multiple importations occurred. These create possible transmission chains. Some of which will die out by chance. One will take off (again by chance) and start to spread. The R value is a measure of the probability that a chain will take off.
It probably arrived multiple times, from Wuhan, where there was ample supply of people who may not have been showing symptoms, from Italy where people appear to have, and even Spain later in the epidemic.
Tracking back to patient zero or trying to estimate how long the virus has been circulating is a nice idea. But things don’t work like that in epidemic land.
Analyses the cases data. Really needs tests to make the most sense. Might look at the national level with tests, cases, admissions and deaths data (that’s the only level that has the consistent Data chain). East Midlands was always an outlier.
Btw you can swap Spain and U.K. in that paper. The two are synonymous as far as The virus is concerned. I’ve stated all along that I don’t believe in exceptionalism. The law of mass action is equally unkind.
Agree with that although it's a bit more subtle than just R. If every case infects 2 new people, then R is two and the first imported case will definitely spread. If 90% of cases infect no-one and 10% infect 20 each, then R is still two but it's quite likely that the first few imported cases will not lead to an outbreak.
I've seen mention of a k parameter to quantify this effect, though not bothered to look up how it's defined.
The R of two can be thought of as the mean of a Poisson process. So on average an individual produces two secondary infections. The variance of a poisson process is the mean, so you can get a range. In fact the number of secondary infections is “over-dispersed” with variance larger than the mean. This can be described with a negative binomial distribution, and k is really a measure of ratio of variance to mean.
One commercial healthcare worker can really screw up your estimation of R. Pun intended. K measures degree of superspreading.
DrJ:
https://twitter.com/AdamJKucharski/status/1280046617614303237
Poor show for the dark blues in corona-science so far.
Ooh they’ve done it nice with county numbers of infections and showing the uptake of the app...
Anyway Overrated..... just get the pub doors open, it’ll all sort itself out.
App looks pretty sensible. Simple and has the right balance of input and information. And the option to opt out. Son2 is off to Carlow to study in September. I’ll have him test it.
By contrast, I suspect that the NHSTT app has competing interests (Kings college for Covid symptoms, Oxford for the location analytics), multiple stakeholders in the development process, and over-ambitious objectives.
Yeah, it sort of feels like they're trying to be Betamax next year, whereas what we need is VHS out there and doing something already and being used.
you have to be kidding
Thin end of the wedge H&S cost clawback in the brave new Brexit?
I'm going for Cummings having his fingers all over this one.
This would mean the first thing NHS workers / careworkers see that impacts on their pay in the new Covid world is a tax increase.
Sunak has confirmed that the BIK test issue is now being reviewed urgently.
I can see this being on Starmer's short list for tomorrow's PMQs.
https://www.bbc.co.uk/news/world-latin-america-53319517
Maybe there is a God
Sorry, I can't wish this virus on anyone.
Usually I'd agree with you matt but he is personally responsible for the deaths of tens of thousands of people, and not just through incompetence and not giving a shit like our halfwit PM, which is bad enough, but willfully. If this takes him out of the picture it's almost bound to save many people from the same fate.
Thin end of the wedge H&S cost clawback in the brave new Brexit?
Probably just existing rules that shouldn't apply to an unprecedented situation. Not the most subtle way of pointing out to the rule makers that they have a problem though!
Sorry, I can’t wish this virus on anyone.
Can’t beat a bit of old school
you reap what you sow
Thou..
On the "benefit in kind" for covid tests. My cynical view is Sunak has been too popular during this crisis and this is intended to reverse that.
Cummings fingerprints allover it
Looks like the scientific thought is leaning towards that a potential Coronavirus transmission vector is airborne after all.
That could put the cat amongst the pigeons.
Good for my particular discipline though (mech/hvac design engineer), every cloud and everything...
To be fair the guidance (REVHA mainly) I’ve read has pretty much pointed towards this from the start (hence my previous ascertain it was airborne, not trying to be smart, I rolled back when I’d read the wider guidance).
Masks indoors and social distancing anyone?
Looks like the scientific thought is leaning towards that a potential Coronavirus transmission vector is airborne after all.
Source please?
Good for my particular discipline though (mech/hvac design engineer), every cloud and everything…
What's your take on efficacy of HEPA filtration? I have 0.1C CTC labs at work that can only keep the air temp at that tight level by recirculating through HEPA, as a result we are looking at self contained breathing apparatus for all in there. HEPA standards seem to test only down to 0.3um, whereas the virus particles are more like 0.05-0.125 I've been told. However, also some evidence HEPA works very well on this size? As a design engineer have you any firm guidance on that?
Just read This artical about common ailments and how they affect mobility rates.
This paragraph in particular must be reported wrong surely
A Chinese study has found people with heart disease, diabetes and cancer had a 79 per cent chance of being admitted to intensive care or dying from the virus, due to their weakened immune systems
Are they saying 79% of folks with diabetes end up in intensive care? I had read the mortality rate was something like x3 normal risk, which whilst not ideal is far far below what the telegraph are reporting.
Is that true, or just massively irresponsible reporting?
Presumably it means 79% of diabetics who are sufficiently ill to be hospitalised (in this study, which will not be the last word on the issue).
Of course, the way it's worded could be interpreted that 79% of diabetics who develop symptoms are in deep trouble...which is just poor reportage. There will be many thousands of diabetics out there for whom Covid is a mild illness, or at least not one that requires hospitalisation.
What's very clear is that Type 1 and 2 diabetes are significant risk factors for poor outcomes. The degree of risk is not entirely clear yet.
I had read the mortality rate was something like x3 normal risk
That's what I keep reading in the references our diabetes clinic staff sent us. More data means the understanding of the real increased risk will be changing though. That x3 isn't a fact set in stone.
Source please?
World Service & R4 Today news bulletins at 5 and 6am respectively. It’s reported in the Guardian (but no direct link, which is why I didn’t post one).
Re. HEPA, it’s pretty specialist stuff (I usually only came across it in association with healthcare and university facilities) and I’ve been out of that particular game a decade now.
The main info source is the REHVA Covd-19 guidance document (April seems to be latest publication date). It clears states airborne transmission through small particles <5 microns. HEPA filters are only mentioned in context of mobile room cleaners.
I don’t mean to sound arsey but I’m governed by Eng Council guidance that affects what I offer as ‘advice’ and competency (just in case you decide to sue me... 🤪). Unfortunately it’s not as easy as just offering my opinion 🤷🏼♂️
Google the rehva guidance doc, it’s pretty readable for the technically minded.
I'm not delighted that Bolsonaro has it but nor am I sorry. I don't give a shit about him.
We've been getting COVID data and analysis internally for a few weeks, we've now put this out on a public site - gives a view worldwide.
https://www.microsoft.com/en-us/ai/ai-for-health-covid-data
Wow. Need to understand the underlying data better, but that looks very good indeed. Will revisit at the weekend.
https://twitter.com/govuk/status/1281151375905304577?s=21
So how do you read that? Is it deliberately ambiguous?
Is it safe do what you like?
Or should you do what you like, but in a way that makes it safe?
It's either deliberately and irresponsibly ambiguous, or completely stupid. Could be either.
I've missed dying...
So the WHO have said that in the last week or so World cases have almost doubled. And today, we are opening out airports to 70 countries without a need to track or isolate passengers.
Is it me, or does this make anyone nervous? I’m assuming they’ll be some kind of COVID checks at airports and the badly affected Americas and Eastern European countries are still on the banned list, but still...
Is it me, or does this make anyone nervous?
Covid-19 is already in circulation here. The government is giving people money to mix indoors in social settings. TTI is limping along. Not sure opening airports is going to make much difference.
I’ve missed dying…
I've missed government competence.
Is it me, or does this make anyone nervous?
Yes, a little.
Although I think air travel is not the top of our list and more normal social settings are the real issue. Especially coming into winter with more indoors stuff prevaling.
At the moment, air traffic probably isn't a big source of new infections, but if/as our domestic spread reduces it could be. I certainly feel that wider/tighter quarantine rules should have been introduced.
If that means fewer holiday flights, the environment will thank us. If that means more people staying at home and keeping UK business going, the economy will thank us. I'm not seeing a downside. If your priority is a fortnight in the sun abroad supporting foreign business and helping to pollute the atmosphere, fair enough, but don't complain if your two weeks away means two weeks in quarantine when you return. There's a bigger picture and wider social responsibility at stake here.
@beej Looks like that map doe snot render correctly on Mac/Chrome, but it does on Mac/Edge.
Cheeky...
Also:
At the moment, air traffic probably isn’t a big source of new infections,
It might not be a big source of new infections in the UK, but people going off on holiday to places like Spain _could_ be a source of new infections in the holiday destination.
FFS, we are supposed to be working together to beat this and yet all this virus seems to do is highlight how totally self-centered [nearly] every damned nation is.
the economy will thank us
except for the bits involved with aviation and holidays
just saying
except for the bits involved with aviation and holidays
We’re at risk of being barred from travelling by the destination countries, that’s also not good for aviation and holidays. The current “slightly open” approach just means longer till these industries can get back towards volume use.
At the moment, air traffic probably isn’t a big source of new infections,
Because its at a vastly reduced level. As pointed out we have enough issues with our own domestic rules, despite the fact - and gladly - cases and deaths continue to fall slowly. My worry is that people are going to come from all over the place and jump straight on the tube from Gatwick & Heathrow bring god knows what with them, which is pretty much how it started in the first place.
Now, I appreciate we can't remain "closed" forever, but with rising global cases, is now really se the right time? See Aus and NZ who have effectively stopped incoming non-nationals.
Which of the countries on the current approved list give you cause for concern? AFAICS for most of them travellers will be at more risk of catching Covid in the UK than we have of them bringing it in.
My worry is that people are going to come from all over the place and jump straight on the tube from Gatwick & Heathrow bring god knows what with them, which is pretty much how it started in the first place.
Given that we're one of the very worst countries in the world for controlling Covid-19 I'd have thought visitors to the UK would be more worried about catching it from someone on public transport or immigration staff when they arrive.
Aye, that's a bit xenophobic, if anything it's Brits going abroad that are the bigger issue, than what anyone coming here does.
