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What you need to know about the virus in China "2019 Novel Coronavirus (2019-nCoV)"

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JIW

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raistlin65 said:
Researchers in Italy have tested an entire community: Coronavirus: "50-75% of cases in Vo 'are asymptomatic. A formidable source of contagion"

Google translation of the first two paragraphs
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If there is exponential growth of positive cases (i.e. discounting recoveries and deaths), the ratio of the number of asymptomatic cases and the number of symptomatic cases stemming from the delay from incubation alone, r_I, is the ratio of increase in the number of positive cases P during the incubation period incubation period T_I in days, i.e.

r_I = (P(t_0 + T_I) - P(t_0))/P(t_0) = P(t_0 + T_I)/P(t_0) - 1 = ((1 + g_P)^(t_0 + T_I))/((1 + g_P)^t_0) - 1 = (1 + g_P)^T_I - 1

Thus, knowing both the incubation period and the ratio of the number of asymptomatic and the number of asymptomatic cases, the growth rate can be calculated by

g_P = (r_I+1)^(1/T_I) - 1

The doubling time is given by t_2 = log(2)/log(1+g).

The numbers in the article of give that r is between 0.5/0.5 = 1 and 0.75/0.25 = 3. The average incubation period seems to be 5 days, which gives a growth rate between 14.9% and 32.0% and a doubling time between 2.5 and 5 days.

The region of Tuscany in which the village is placed, reported its first two positives on 25/02 and as of 16/03 has 841 positive cases which gives an average growth rate of 35.2% and a doubling time of 2.3 days and thus a ratio of asymptomatic cases to symptomatic cases of 3.53, i.e. 77.9% of positive cases are asymptomatic. While this is a bit higher than the article states, regional differences may make up what remains of the discrepancy.

Thus (and tl;dr), in the least, growth over the incubation period alone may explain most of the great share of asymptomatic positive cases.
 
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Wes

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Soundstage said:
If you don't adjust the price, then just set a maximum of products sold to a client. As simple as that. Because people are panicking, and buy much more than what they need anyway.
Either you go for the strict limit, or you let the price floating. The authorities are just plain stupid, blaming someone for an issue they created themselves.
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what the guy did has been illegal for centuries - the first legal case I know of involved lack of water on a sailing ship
 
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digicidal said:
So many of the responses to this are completely antithetical to the perceived benefits compelling them. Our local grocery stores (well, thankfully only one chain so far) has enacted a set of new policies "to protect the safety of our customers and staff" - direct quote from the sign on the door. So were the measures wiping down the registers more regularly? Nope. Limiting quantities of supplies? Nope. They reduced their operating hours from 6am-1am to 8am-10pm, and added a restriction to no more than 25 customers at a time in the store. :rolleyes:

So now, rather than allowing individual separation - there's a huge crowd bunched up at the doors waiting to get in... and once they do get in - they naturally pile up way more than they need for 2 weeks. Of course, I probably would too if I hadn't scrubbed the whole mission once I saw the crowd - especially if I believed I'd have to go through the same thing in 2 more weeks when everything is much worse!

It reminded me of what Governor Cuomo's ridiculous announcement and guidelines were.

Although not expressed in the printed version I linked, in two separate press conferences yesterday he stated that people "should avoid travel between the times of 8pm and 5am". WTF? You want to keep everyone from gathering in groups of 50 (his guidelines) or worse 10 (Trump's yesterday revision) but you simultaneously want all activities to be restricted by 9 hours... as well as restricting bars and restaurants to delivery only. Well, the reality is that many here have just closed entirely - even for delivery/take-out - so again higher densities in smaller time windows. :facepalm:

Here's an idea... how about we hire some of those people that are laid off already (there's thousands here, all the casinos just fired everyone immediately for the most part) and run the grocery stores and any delivery-capable restaurants 24 hours per day. That way those looking for a "lower-risk-time" could go shopping at midnight if they choose (which is when I've always gone to the store that now has the new rules - and now can't go there at all unless I want to stand in a crowd for an hour). :mad:
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Australian supermarkets fixed this issue by limiting purchases and increasing delivery trucks after council approvals since only a certain number of delivery trucks are allowed in a day in a given suburb.

Certain items are only allowed to be purchased in fixed quantities, no price hikes and special hours for the elderly and the disabled.
 
raistlin65

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Medical research showing people with mild or no symptoms account for a large number of coronavirus carriers:

Substantial undocumented infection facilitates the rapid dissemination of novel coronavirus

Abstract
Estimation of the prevalence and contagiousness of undocumented novel coronavirus (SARS-CoV2) infections is critical for understanding the overall prevalence and pandemic potential of this disease. Here we use observations of reported infection within China, in conjunction with mobility data, a networked dynamic metapopulation model and Bayesian inference, to infer critical epidemiological characteristics associated with SARS-CoV2, including the fraction of undocumented infections and their contagiousness. We estimate 86% of all infections were undocumented (95% CI: [82%–90%]) prior to 23 January 2020 travel restrictions. Per person, the transmission rate of undocumented infections was 55% of documented infections ([46%–62%]), yet, due to their greater numbers, undocumented infections were the infection source for 79% of documented cases. These findings explain the rapid geographic spread of SARS-CoV2 and indicate containment of this virus will be particularly challenging.
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Soundstage said:
He was only able to do that because the price is not adjusted. By the way I prefer to have someone like him selling the product at 10 times the price rather than a shortage of the product. He is filling the gap. The market is not correcting for the increase in demand. So rather than passively waiting that all supplies are gone, he is making sure that everyone will have some.
And there is no monopoly here.
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The suppliers may well have the ability to meet demand at the chosen price but only by spacing sales in time due to stocking capacity being limited and production and delivery taking time. Unless some prospective buyers having to purchase later than others creates great suffering, a monopsonist (one buyer purchasing all goods) exploiting this to (temporarily) create a monopoly is a market failure.

If the guy in the article could anticipate a demand increase, the store managers may as well also have and set up a corresponding delivery schedule. Also, the firms whose business depends on judging the market for their product correctly, would have made an offer for greater delivery to the store based on them anticipating excess demand.

Rather than filling a gap, the guy created one where none likely would have existed and (at least partly) filled it by offering for sale all (or most of) the available supplies. At least locally, he thus created a monopoly (after he became a monopsonist).
 
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andymok

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gikigill said:
Australian supermarkets fixed this issue by limiting purchases and increasing delivery trucks after council approvals since only a certain number of delivery trucks are allowed in a day in a given suburb.

Certain items are only allowed to be purchased in fixed quantities, no price hikes and special hours for the elderly and the disabled.
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They are experienced after the buying of powdered milk I guess
 
DuxServit

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1584492403032.png

https://www.channelnewsasia.com/new...pore-malaysia-asean-stay-home-notice-12539952
 
Xulonn

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A current Panama COVID-19 update:

My neighbor Janet just messaged her fellow American expat tenants here at our little cluster of rental units. About an hour ago she talked to Pepe, a 40-something Panamanian who lived in the US as a young man, then Costa Rica for 8 years, and now rents a tiny townhouse at the back of the casite of Janet and her husband Les, a couple who recently moved here from Homer, Alaska.

I thought I would share how in tune and proactive the Panamanian government is compared to the USA. Pepe just stopped by to let us know what is on Panamanian TV. Briefly he said the government is assuring food, medications and basics for the country. For instance there is a stockpile of rice through July. Medications are available and will continue to be brought in. Money will be provided for those in need. Customers can delay utility payments. In other words, the government is really being responsive so that people can have some belief that basic goods will be available, and life as normal might return sooner rather than later. As Pepe pointed out, if people stay home and hunker down with assurances from the government that basics will be provided, then hopefully Panama will see fewer COVID-19 infections.
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Edit: Panama Coronavirus news from Panamá América (Google translation page). Panama is receiving getting help in managing the pandemic from the Chinese government. Panama has a close relationship with China because of the Panama Canal and its importance to world trade. We are a small country, but important to the world economy.
 
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Doodski

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Thankfully the community beer and wine store is fully operational ;) ...and I went a got a new video card to keep myself occupied catching up on 3D stuff ;)
 
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