Coronavirus outbreak

[twentysix by twentyfive]

Just reading about what they say is "mass cancellations of Majorca cycling holidays".
My May cycling holiday is looking doubtful.
Not the worst thing that could happen to me compared to many poor souls and tbh I am expecting to lose it and possibly the money. Everything in context eh
https://www.majorcadailybulletin.co...ajorcan-hoteliers-devastated-coronavirus.html

Just go. Risk there is the same here. Unless there is an official clamp down in which case find a people trafficker. Roads will be quiet 👍

 

[MichaelO]

Really? If you had done the calculations on the numbers here (have you seen the curve in there?), you would have found that the average increase on the previous day, for the last 7 days, is 35.7%. If that is not exponential growth, what is?

I'd say the Italian cases were "growth" not exponential growth. It has stayed relatively steady at 25% increase per day. Exponential growth would see the % increase being higher each day for a sustained period, surely?

Edit: I could be horribly wrong here....

 

[glasgowcyclist]

It is interesting you show this, because the graph is somewhat famous, or more accurately notorious, because it is completely misleading. If we think the CDC (i.e. read USA) is credible in fighting the virus, we are doomed, aren't we?

Think about it, in Hubei, sure it was a sharp fast increase (like the red curve), but through their measures they managed to stop the rate of infection at 0.17% infected (i.e. c100,000) of the c60 millions. Tell me, if they did not practice social distancing, would the rate of infection be less than 0.17%, or higher? or a higher % on the whole 1.4 billion population of China?

In other words, is it not blindingly obvious that a proactive response will give you the red curve, while without it will deliver you a curve that is not shown on the graph at all?

To put it simply, the above chart is a joke, because in reality the only available options are: 1) a proactive hit on the spread, which would make it look like the red, while 2) the ONLY other alternative would be "like" the blue, except rising just as fast as the red, but reaching much higher, for longer, and HUNDREDS of times larger - that is what it will look like without proactive measures.

If anyone disagrees, please describe what other alternative scenario and result can possibly exist, and why?

I read that graph as: red zone = result of no control measures, blue zone = result of control measures. If we want to flatten the peak of infections & fatalities, don't we need to implement protective measures?

 

[Rocky]

I'd say the Italian cases were "growth" not exponential growth. It has stayed relatively steady at 25% increase per day. Exponential growth would see the % increase being higher each day for a sustained period, surely?

Edit: I could be horribly wrong here....

Exponential......starts slowly then grows quickly. I think we are still on the early part of the graph.......

 

[MartinQ]

I'd say the Italian cases were "growth" not exponential growth. It has stayed relatively steady at 25% increase per day. Exponential growth would see the % increase being higher each day for a sustained period, surely?

Edit: I could be horribly wrong here....

Yes, you are .
That is the definition of exponential growth.

 

[MichaelO]

Yes, you are .
That is the definition of exponential growth.

🤦‍♂️

 

[stowie]

Why do you think people are buying toilet rolls? Is it because of a fear we may run out or because people are saying "Everyone's buying toilet rolls" while others are saying "We're in a phase of exponential growth"

The toilet roll thing does seem bizarre. I am told that the origins are in Asia where some regions really were running out of toilet roll - which was produced almost exclusively in a quarantined area thus there really was a shortage as manufacturing and distribution was stopped.

I cannot be too judgmental on these people (well OK, just a bit judgmental).

The industry I work in has similar issues. Long manufacturing time (and $$$$$ setup costs) coupled with highly flexible demand. I have seem large multinationals with all sorts of complex JIT supply chains and people in charge with lots of impressive qualifications panic buying product for which they have no immediate need simply because everyone else is. And then it either sitting in stock, or being resold at a loss when the situation resolves and they need to reduce inventory for the end of quarter shareholder report. The sort of corporate equivalent of going out to Costco and buying your own body weight in bog-roll then a week later realising that the outcome has been simply that your house is full of toilet paper.

If the corporations who pride themselves in streamlined and efficient supply chains succumb to it, I think the average person is likely to as well.

 

[Mo1959]

Just popped into the Co-op for some munchies since it’s so miserable and noticed the toilet roll shelves were empty! I find it highly amusing and a bit baffling!

 

[Joey Shabadoo]

Just popped into the Co-op for some munchies since it’s so miserable and noticed the toilet roll shelves were empty! I find it highly amusing and a bit baffling!

What did you get to eat instead?

 

[RecordAceFromNew]

The chart assumes that stopping the spread completely is not achievable, so the total infections (area under the curve) is the same whatever.

That assumption depends on transmission rates, duration and severity of restrictions, time to get a vaccine etc.

Until the virus has been eradicated, you can't say what shape the final curve will be. It may well return rapidly as soon as restrictions are lifted, or it may abate in the summer and not return, or it may abate then return in the winter.

The virus has not been eradicated, in China or anywhere else.

All you can say about the China results is that they are very impressive in the short term (if you trust them, of course).

The thing is while you do not believe in Chinese numbers, do you believe the scientific explanation why it can and should be controlled, which is little more complicated than the fact that isolation stops transmission? If you think the blue curve is meaningful, aren't you saying it can't be controlled (as you say the chart assumes stopping the spread is NOT achievable)?

You can disbelieve figures from China, but do you also disbelieve this*, i.e. that the social distancing efforts in Hongkong actually also stopped common flu in its track?

* google "Hong Kong’s coronavirus response leads to sharp drop in flu cases" in browser's incognito tab if paywall stops you

 

[Mo1959]

What did you get to eat instead?

Crisps and cookies

 

[RecordAceFromNew]

I'd say the Italian cases were "growth" not exponential growth. It has stayed relatively steady at 25% increase per day. Exponential growth would see the % increase being higher each day for a sustained period, surely?

Edit: I could be horribly wrong here....

It is exponential growth*, because the growth on the PREVIOUS day stays roughly the same. The curve is not straight, it soars. For a 30% per day increase for 10 days from 100, instead of 30 increased each day to 400 by day 10, it would become 1378 instead.

Infection is exponential not linear until it is stopped or saturated, because of the network effect - 1 person transmit to 2, 2 to 4, 4 to 8 etc.

* wiki description: Exponential growth is a specific way that a quantity may increase over time. It occurs when the instantaneous rate of change (that is, the derivative) of a quantity with respect to time is proportional to the quantity itself.

 

[roubaixtuesday]

The thing is while you do not believe in Chinese numbers, do you believe the scientific explanation why it can and should be controlled, which is little more complicated than the fact that isolation stops transmission? If you think the blue curve is meaningful, aren't you saying it can't be controlled (as you say the chart assumes stopping the spread is NOT achievable)?

You can disbelieve figures from China, but do you also disbelieve this*, i.e. that the social distancing efforts in Hongkong actually also stopped common flu in its track?

* google "Hong Kong’s coronavirus response leads to sharp drop in flu cases" in browser's incognito tab if paywall stops you

I did not say I do not believe the China numbers, merely trying to reflect there is scepticism about them.

But the point remains; unless the social distancing is kept in place for ever (or until vaccine), the virus will return, and the area under the curve will be the same whatever is done.

 

[Dave7]

Just popped into the Co-op for some munchies since it’s so miserable and noticed the toilet roll shelves were empty! I find it highly amusing and a bit baffling!

Will it still be amusing if you get the squits and have to use grease proof paper or kitchen foil

 

[roubaixtuesday]

Probably not too far off in China. 60,000 of the 80,000 infected have made a full recovery - "only" 17,000 active cases remain.

It's a massive way off eradicated.

To eradicate it requires zero cases anywhere for at least two weeks.

Just one case can kick off the whole epidemic again.