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Tags Coronavirus , diseases

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Old 17th April 2020, 06:43 AM   #2841
lomiller
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Originally Posted by Fast Eddie B View Post
After several days of zero new daily deaths, I noticed that China is showing 1,290 new deaths today. Probably an anomaly due to less than daily reporting of their numbers, but still an interesting data point.
These are older deaths not previously attributed to COVID-19 that were reclassified. This doesn't reflect people who have died in the last day.
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Old 17th April 2020, 07:16 AM   #2842
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As to the German numbers - everybody know how good we are at following orders, and everybody who met us knows how much social distancing we practice voluntarily compared to Spain, Italy and France...
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Old 17th April 2020, 07:55 AM   #2843
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Originally Posted by Fast Eddie B View Post
After several days of zero new daily deaths, I noticed that China is showing 1,290 new deaths today. Probably an anomaly due to less than daily reporting of their numbers, but still an interesting data point.
So the China claims is from correcting presumably overwhelmed data from months ago when they were in the thick of things. Sure.

More likely they have known about this for quite a while but now it's politically acceptable to reveal it as the US has recently been saying that deaths in nursing homes, a pretty big part of COVID deaths, weren't counted in some places as a matter of policy. Also NY didn't report suspected COVID deaths when some 200/day were dying at home and never hospitalized.

Not surprising given that the disease often causes a person to descend rapidly in a few hours.

I wonder if some of this is why Italy hasn't been seeing the decrease in daily deaths that were projected over the last week.
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Old 17th April 2020, 08:11 AM   #2844
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Apologies if this has already been posted, I have been following the Covid 19 politics rather than medical thread;

http://inproportion2.talkigy.com/ind...nsmission.html

"Sharing indoor space is a major SARS-CoV-2 infection risk. All identified outbreaks of three or more cases occurred in an indoor environment

By early April 2020, the COVID-19 pandemic had infected nearly one million people and had spread to nearly all countries worldwide. It is essential to understand where and how SARS-CoV-2 is transmitted.

Case reports from 320 municipalities in China were studied, not including Hubei province, between 4 January and 11 February 2020. All outbreaks involving three or more cases were studied

Three hundred and eighteen outbreaks with three or more cases were identified,involving 1245 confirmed cases in 120 prefectural cities."
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Old 17th April 2020, 08:17 AM   #2845
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Originally Posted by Myriad View Post
I've added the number of test results reported per day, and the percent positive of those test results, to the table. (Also added today's figures.)

The columns are:
date
total confirmed cases to that date
increase factor of total confirmed cases for the day (rounded to two decimal places)
new confirmed cases for the day
number of test results for the day
percentage of test results positive

"S" indicates Saturdays and Sundays, which might affect the timing of reporting and thus shift the numbers of cases between days.

"*" and "+" indicate a new all-time high for new confirmed cases on that day.

Code:
3/21     525   1.27    112   S
3/22     646   1.23    121   S
3/23     777   1.20    131
3/24    1159   1.49    382   4827    8% +  <--- business closures / lockdown
3/25    1838   1.59    679   6045   11% +
3/26    2417   1.32    579   3827   15%
3/27    3240   1.34    823   5750   14% +
3/28    4257   1.31   1017   5678   18% * S
3/29    4955   1.16    698   4017   17%   S
3/30    5752   1.16    797   3727   21%
3/31    6620   1.15    868   4142   21%
4/01    7738   1.17   1118   4803   23% +
4/02    8966   1.16   1228   4870   25% +
4/03   10402   1.16   1436   6354   23% *
4/04   11736   1.13   1334   5838   23%   S
4/05   12500   1.07    764   3137   24%   S
4/06   13837   1.11   1337   4992   27%
4/07   15202   1.10   1365   4915   28%
4/08   16790   1.10   1588   6167   26% +
4/09   18941   1.13   2151   7447   29% *
4/10   20974   1.11   2033   7414   27%	
4/11   22860   1.09   1886   6404   29%   S
4/12   25475   1.11   2615   7954   33% * S
4/13   26867   1.05   1392   5319   26%  <--- 1.5 hr. change in data closeout time
4/14   28163   1.04   1296   4502   29%
4/15   29918   1.06   1755   5472   32%
4/16   32181   1.08   2263   8750   26%
It's pretty clear that day to day differences in the timing of test result completion (or reporting) cause day to day variations in the numbers. For instance, it's pretty obvious that the anomalously low figure on 4/5 is the result of fewer test cycles completed that day. However, such delays can only shift "new" cases by a day or two. Longer-term trends such as the drop in rate from the "blue" period to the "red" period can't just be an artifact of such anomalies.

It also appears the figures from 4/14 and 4/15 were artificially low due to fewer (relative to prior days) test cycles being completed on those days, pushing those results forward to today's all time high number of test results and today's higher (but not all-time high) number of new cases. A similar weekday effect (with fewer results reported earlier in the week and more on Thursday and Friday) might have happened last week as well, but no such pattern extends to previous weeks.

On 3/24, the first date on which I could derive exact figures for new test results that day from the data available, testing in Massachusetts had just ramped up to an effective level, with over a dozen different labs reporting results, versus three labs two days earlier. (The 4,827 tests completed on the 24th were over 35% of the total number of MA tests completed, as of that date, since testing began.)

It's hard to pin down a reason for the low early percentage of positive tests, but the percentage itself speaks against there being a large backlog of symptomatic patients who hadn't yet been tested, thus artificially lowering the early case figures. The percent positive trended upward over time, but settled in the range of about one fourth to one third of all test results after the first week. More precautionary (as opposed to diagnostic) testing would tend to decrease the positive rate, while a dramatic proliferation of asymptomatic cases would tend to increase it. Different effects of that nature can't be separated out. But the lack of large (let alone sudden) changes in either of those stats in the past 3 weeks does not support any hypothesis that the apparent case rate is being artificially boosted by increased testing capturing a higher percentage of the actual cases, nor artificially suppressed by any drop-off in testing.
The % of tests which came back +ve is a good addition to the data.

However, there may still be a strong selection effect here ... I read somewhere that you need ~20% (or fewer) of your tests to be +ve before you can say you're likely sampling the population well enough.

I think it likely that there are considerable selection effects showing in the data. For example, the incidence of covid-19 is surely not random throughout all who are (or were) in MA at the time; the population is not homogeneous. There are likely several kinds of inhomogeneity, not only geographic. So as the testing samples more or less from one or another sub-population, so the changes in numbers of confirmed cases changes too.

The pattern you're seeing in the data may be only indirectly related to changes happening the spread of covid-19.

Another factor that may be at play: test sensitivity. No test is perfect, there will always be false positives and false negatives. It seems very unlikely that the %-ages of each, for each of the (many?) types of tests used over this period are the same*. Hence the patterns in the data may, to some extent, reflect differences in the distributions of test sensitivity throughout the period.

*while strange patterns may emerge even if they are, the fact that the reported %-age of +ves is ~flat suggests this effect would be minimal
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Old 17th April 2020, 08:21 AM   #2846
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Most of the top runners now seem to have hit a plateau in daily cases, rather than peaking. The length of the plateaux is the next big question. What was that popular article a few years back about if you don't know where you are in a process you're probably in the middle?
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Old 17th April 2020, 08:29 AM   #2847
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Originally Posted by sphenisc View Post
Most of the top runners now seem to have hit a plateau in daily cases, rather than peaking. The length of the plateaux is the next big question. What was that popular article a few years back about if you don't know where you are in a process you're probably in the middle?
One other (at least for the US): are there any "late comer" states which will put on a burst of speed and overtake the current front runners?

Or: will Texas become the new New York (and if so, when)?
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Old 17th April 2020, 08:37 AM   #2848
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UK to start contact tracing again


https://www.theguardian.com/world/20...e_iOSApp_Other
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Old 17th April 2020, 08:44 AM   #2849
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Daily Mail: Some Florida beaches to begin reopening today.
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Old 17th April 2020, 08:48 AM   #2850
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Originally Posted by Darat View Post
Why SK? They immediately started rigorous testing and extensive contact tracing with then enforced quarantine as soon as they had any confirmed cases. They had the likes of drive thruí testing stations before the rest of us and so on. They really do seem to have known what to do and when to do it.

I do wonder if it is because they have war gamed a lot of attacks by NK, such as a biological weapon attack so had plans they could immediately pull off the shelf.
No, it is from previous experience with SARS and MERS
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Old 17th April 2020, 08:50 AM   #2851
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Originally Posted by sir drinks-a-lot View Post
Still doesn't seem to be showing 30K deaths in the US yet.

https://coronavirus.jhu.edu/us-map

Am I looking in the wrong place?
Iím guessing your theory that we will be talking about this as much as we talk about finger spinners in six months is looking on shaky ground right now.
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Old 17th April 2020, 08:57 AM   #2852
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Originally Posted by angrysoba View Post
I’m guessing your theory that we will be talking about this as much as we talk about finger spinners in six months is looking on shaky ground right now.
No, I still think it's likely that it will be very largely under control in the US by then. I also think there will be much fewer deaths than have been predicted by many. Of course it's now apparent we'll be talking about it for a long time, but i think it will be talking about the economic fallout, the response, future possible pandemics, etc.

Now, any answer to the question you quoted? The Johns Hopkins site still doesn't seem to be showing 30K deaths in the US. Am I looking in the wrong place?
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Old 17th April 2020, 09:17 AM   #2853
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Originally Posted by Darat View Post
Policy is not the same as doing.

SK: we plan on doing a,b,c to get to X
SK: did a,b,c
SK: got to X

UK: we plan on doing a,b,c to get to X
UK: did a,c
UK: didnít get to X

You canít say the plan didnít work in the UK because the plan wasnít followed.

So again what I said is correct regardless of the inability of our government to carry it out.
Sorry you are wrong.

That you want it so does not make it so. You are expected to provide evidence to support your case please provide evidence that the UK did not follow a policy of contact tracing.

This is an example of trans-national contact tracing during the containment phase in Europe of the covid-19 pandemic.
https://www.bbc.co.uk/news/uk-51442314

The UK (and other European countries) did follow the plan. The plan is set out in ECDC pandemic plan*, at scenario 1 and 2 containment is the main plank of the policy with contact tracing and isolation. Scenario 3 which the UK entered mid March is the mitigation phase when contact tracing ceases as it has been ineffective. Arguably it may have worked better for Germany than the rest of Europe, but it was not a success. This was not a unique failure to the UK but all European countries. When a policy failed in many countries and was a success in only one before repeating the previously failed policy it is sensible to enquire why it worked in one place and failed in many.

*https://www.ecdc.europa.eu/sites/def...y-COVID-19.pdf
https://www.gov.scot/publications/co...tracing-works/
https://publichealthmatters.blog.gov...ntact-tracing/
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Old 17th April 2020, 09:23 AM   #2854
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Originally Posted by Dr.Sid View Post
Big difference is also when those policies start. What's easy with 10 people per day, cannot be possible with 1000 people per day.
I don't know specific timeline in UK, but in local news UK was reported from the start as 'let it run wild' country, and only later they were supposed to make their mind.
This is absolutely untrue. Up until mid March every identified case in the UK was contact traced. E.g. a report of contact tracing from 12/03/20
https://www.shb.scot.nhs.uk/board/ne...irmedCases.pdf
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Old 17th April 2020, 09:25 AM   #2855
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Originally Posted by JeanTate View Post
The % of tests which came back +ve is a good addition to the data.
This statistic can give a clue as to which countries are trying to get ahead of the spread (unless a country is testing randomly or trying to test everyone as Iceland is). Countries in which less than 10 percent of tests are positive tend to have the lowest fatality rates. Raw counts of people tested can be misleading; for example, South Korea does not have an especially high percentage of people tested because the spread there is slow enough that they haven't had to test a lot of people for the past few weeks. Unfortunately, it means that the US has to double its testing capacity before anyone can think about lessening restrictions.
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Old 17th April 2020, 09:28 AM   #2856
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Man everyone is sending me this to prove this covid stuff is fake. The level of confidence he talks with and says hes a doctor gets all the easily snowed going. I hope jeff Holiday sees this

https://www.youtube.com/watch?v=BzRbq9XJ7mA
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Old 17th April 2020, 09:29 AM   #2857
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Originally Posted by Darat View Post
UK to start contact tracing again


https://www.theguardian.com/world/20...e_iOSApp_Other
This article says the UK contact traced until 12/03; why do you believe that the UK will start contact tracing again when you don't believe it did so in the first place?
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Old 17th April 2020, 09:29 AM   #2858
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Originally Posted by Planigale View Post
Sorry you are wrong.

That you want it so does not make it so. You are expected to provide evidence to support your case please provide evidence that the UK did not follow a policy of contact tracing.

This is an example of trans-national contact tracing during the containment phase in Europe of the covid-19 pandemic.
https://www.bbc.co.uk/news/uk-51442314

The UK (and other European countries) did follow the plan. The plan is set out in ECDC pandemic plan*, at scenario 1 and 2 containment is the main plank of the policy with contact tracing and isolation. Scenario 3 which the UK entered mid March is the mitigation phase when contact tracing ceases as it has been ineffective. Arguably it may have worked better for Germany than the rest of Europe, but it was not a success. This was not a unique failure to the UK but all European countries. When a policy failed in many countries and was a success in only one before repeating the previously failed policy it is sensible to enquire why it worked in one place and failed in many.

*https://www.ecdc.europa.eu/sites/def...y-COVID-19.pdf
https://www.gov.scot/publications/co...tracing-works/
https://publichealthmatters.blog.gov...ntact-tracing/
The article I linked to provides the details of the failings of the government not to follow an effective plan.

You need to keep your partisan political views out of these discussions.
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Old 17th April 2020, 09:30 AM   #2859
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Originally Posted by Planigale View Post
This article says the UK contact traced until 12/03; why do you believe that the UK will start contact tracing again when you don't believe it did so in the first place?
I never claimed that.
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Old 17th April 2020, 09:55 AM   #2860
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Originally Posted by Darat View Post
The article I linked to provides the details of the failings of the government not to follow an effective plan.

You need to keep your partisan political views out of these discussions.
What political views? I have stuck strictly to the facts and evidenced the facts. I have made no political points. Disagreeing with you is not political. I think you are projecting; you clearly do have a political agenda, when someone disagrees with you, you consider that to be political. It may simply be because you are wrong.

ETA To be helpful could you quote the bit in the article or clearly point to the bit in the article so I can address the issue, or admit being wrong.

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Old 17th April 2020, 10:02 AM   #2861
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Originally Posted by sir drinks-a-lot View Post
No, I still think it's likely that it will be very largely under control in the US by then. I also think there will be much fewer deaths than have been predicted by many. Of course it's now apparent we'll be talking about it for a long time, but i think it will be talking about the economic fallout, the response, future possible pandemics, etc.

Now, any answer to the question you quoted? The Johns Hopkins site still doesn't seem to be showing 30K deaths in the US. Am I looking in the wrong place?
33,898 - https://gisanddata.maps.arcgis.com/a...23467b48e9ecf6
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Old 17th April 2020, 10:19 AM   #2862
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I don't know what to think of this.

Quote:
A million doses of a potential COVID-19 vaccine being developed by British scientists are already being manufactured and will be available by September, even before trials prove whether the shot is effective, the team said on Friday.
https://www.cbc.ca/news/health/uk-co...cine-1.5535644
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Old 17th April 2020, 10:38 AM   #2863
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Originally Posted by marting View Post
Chicago hospital treating severe Covid-19 patients with Gilead Sciencesí antiviral medicine remdesivir in a closely watched clinical trial is seeing rapid recoveries in fever and respiratory symptoms, with nearly all patients discharged in less than a week, STAT has learned.
I saw that and it's potentially excellent news. The numbers look pretty good, but we'll have clearer results in days.

Originally Posted by JeanTate View Post
The reason given: re-assessment of deaths, especially in the early days of the (then) epidemic in Wuhan.

I do not know how common this is, in general, for deaths of any kind, but for covid-19 - especially in China - I think it will be quite common.
It seems to pretty common around the world that many Covid deaths aren't being recorded as such. I doubt we'll ever know the true number.

Originally Posted by Childlike Empress View Post
As to the German numbers - everybody know how good we are at following orders, and everybody who met us knows how much social distancing we practice voluntarily compared to Spain, Italy and France...
The Poms are among the more stand-offish people as well, but it didn't help them.

Originally Posted by eerok View Post
I don't know what to think of this.
Living in hope is all, and preparing for success, if it happens. It's what Bill Gates is doing with building facilities manufacturing unknown treatments.

If one of them works, we're going to need several billion doses and pre-preparing a million for the most vulnerable in your country seems fairly sensible.
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Old 17th April 2020, 10:41 AM   #2864
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Originally Posted by JeanTate View Post
Maybe I won't get ninja'd this time ...


The % of tests which came back +ve is a good addition to the data.

However, there may still be a strong selection effect here ... I read somewhere that you need ~20% (or fewer) of your tests to be +ve before you can say you're likely sampling the population well enough.

I think it likely that there are considerable selection effects showing in the data. For example, the incidence of covid-19 is surely not random throughout all who are (or were) in MA at the time; the population is not homogeneous. There are likely several kinds of inhomogeneity, not only geographic. So as the testing samples more or less from one or another sub-population, so the changes in numbers of confirmed cases changes too.

The pattern you're seeing in the data may be only indirectly related to changes happening the spread of covid-19.

Another factor that may be at play: test sensitivity. No test is perfect, there will always be false positives and false negatives. It seems very unlikely that the %-ages of each, for each of the (many?) types of tests used over this period are the same*. Hence the patterns in the data may, to some extent, reflect differences in the distributions of test sensitivity throughout the period.

*while strange patterns may emerge even if they are, the fact that the reported %-age of +ves is ~flat suggests this effect would be minimal

Mostly fair points, though I haven't seen any actual evidence that the test used in MA has changed at all during the recorded period.

I agree that the amount of testing is insufficient, even though the state has been touting its high number of tests (relative to other states and nations) all along. I don't know if the limiting factor on testing is still the number of tests available (as it was early on, before March 24th), or the number of people who can be swabbed per day by the available medical personnel, or the number of people able to get medical authorization to be tested. These factors can be interdependent; for example, if test center personnel were sitting idle because doctors weren't ordering a lot of tests, one might expect the medical authorities to loosen the criteria for authorization, and so forth.

The variations in tests completed per day could be driven by changes in the input stream, rather than by e.g. backlogs at labs. I know drive-in test centers have been opening at specific locations for one-day periods; how many such centers are open per day and how much "business" they do at a given location could vary, explaining the day to day variations in numbers of test results reported. If fewer drive-in or other test locations are being opened on weekend days, with the expected processing and results reporting delays, that could explain the recent Mon-Tue lulls.

There being any significant aspect of the disease process behind the stair-step pattern is therefore questionable, but the long-term changes in rate of increase of new confirmed cases per day are still well-evidenced, and are consistent with the curves now playing out in all different phases in many places.
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Old 17th April 2020, 10:42 AM   #2865
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Interesting news off USS Theodore Roosevelt. They're testing the entire crew and after 95% of that, found 600 infections, 60% of which were asymptomatic. That's sure to include a number that were pre-symptomatic, given the long incubation period, but it is more evidence that somewhere around half of all cases are asymptomatic.

https://www.msn.com/en-us/news/us/co...ee/ar-BB12Jojz
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Old 17th April 2020, 10:49 AM   #2866
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Originally Posted by The Atheist View Post
Interesting news off USS Theodore Roosevelt. They're testing the entire crew and after 95% of that, found 600 infections, 60% of which were asymptomatic. That's sure to include a number that were pre-symptomatic, given the long incubation period, but it is more evidence that somewhere around half of all cases are asymptomatic.

https://www.msn.com/en-us/news/us/co...ee/ar-BB12Jojz

Interesting, and looking forward to learning the pre-symptomatic prevalence.

I have to go back and re-find a reference, but it's been reported in Boston that of the 146 non-symptomatic cases found at the Pine Street Inn (homeless shelter) nearly two weeks ago, only one (!) went on to require hospitalization, and "some" (unspecified number) developed "mild cold symptoms."
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Old 17th April 2020, 10:49 AM   #2867
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Originally Posted by The Atheist View Post
Interesting news off USS Theodore Roosevelt. They're testing the entire crew and after 95% of that, found 600 infections, 60% of which were asymptomatic. That's sure to include a number that were pre-symptomatic, given the long incubation period, but it is more evidence that somewhere around half of all cases are asymptomatic.

https://www.msn.com/en-us/news/us/co...ee/ar-BB12Jojz
Well, asymptomatic at the time of testing, but symptoms could still follow?

Or is/was everyone tested asymptomatic already beyond the two weeks?
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Old 17th April 2020, 11:21 AM   #2868
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Originally Posted by carlosy View Post
Well, asymptomatic at the time of testing, but symptoms could still follow?

Or is/was everyone tested asymptomatic already beyond the two weeks?
Yep. Very important difference. Normally, whether a person is symptomatic is noted at the time the test is given. It's rapidly spreading and positive tests occur days before symptoms. 60% asymptomatic will be much lower once the spreading stops and 10 days or so go by.
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Old 17th April 2020, 11:26 AM   #2869
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Originally Posted by Myriad View Post
Interesting, and looking forward to learning the pre-symptomatic prevalence.

I have to go back and re-find a reference, but it's been reported in Boston that of the 146 non-symptomatic cases found at the Pine Street Inn (homeless shelter) nearly two weeks ago, only one (!) went on to require hospitalization, and "some" (unspecified number) developed "mild cold symptoms."
I've heard the incubation period of Covid-19 as being from 5-14 days. I wonder how likely it is that it could be longer. Even 14 days sounded long to me, but I'm not a virologist by any stretch, and a quickly found source online suggests some viruses have significantly longer incubation periods.
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Old 17th April 2020, 11:39 AM   #2870
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Testing: specificity, sensitivity, false positives and negatives, Bayes

If you know your BayesWP, you already know that the numbers of false positives and false negatives, in a covid-19 test, have important implications for conclusions you draw from the results.

In medical tests, I learned recently that there are two metrics regarding the "falses", specificity (roughly, does this test detect covid-19 and only covid-19?), and sensitivity (roughly, how completely does this test detect covid-19).

This fairly recent STAT article explains some testing-related challenges (I think STAT is a reliable source): "Covid-19 testing: overcoming challenges in the next phase of the epidemic" (link).

A covid-19 test that is both 100% specific and 100% sensitive may exist in some alternative universe; in ours, not so much.

When you're desparately short on tests - still true throughout the US, sadly - it likely doesn't merit wasting brain cycles thinking about rates of "falses", for this or that covid-19 test, done here or there.

However, if you want to understand the reported test results - from VÚ, Diamond Princess, Theodore Roosevelt, Iceland, or even Telluride - you do. Apparently even whoever is in charge of China's borders does too: 14 day mandatory quarantine for all international arrivals, no exceptions (a similar rule may apply in Australia too, especially since the Ruby Princess fiasco).

If the US CDC - and equivalents elsewhere - are on the ball, one criterion for giving approval to a covid-19 test would be reliable data on that test's specificity and sensitivity, and ensuring that that data is made public.
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Old 17th April 2020, 11:49 AM   #2871
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Originally Posted by Myriad View Post
Mostly fair points, though I haven't seen any actual evidence that the test used in MA has changed at all during the recorded period.

I agree that the amount of testing is insufficient, even though the state has been touting its high number of tests (relative to other states and nations) all along. I don't know if the limiting factor on testing is still the number of tests available (as it was early on, before March 24th), or the number of people who can be swabbed per day by the available medical personnel, or the number of people able to get medical authorization to be tested. These factors can be interdependent; for example, if test center personnel were sitting idle because doctors weren't ordering a lot of tests, one might expect the medical authorities to loosen the criteria for authorization, and so forth.

The variations in tests completed per day could be driven by changes in the input stream, rather than by e.g. backlogs at labs. I know drive-in test centers have been opening at specific locations for one-day periods; how many such centers are open per day and how much "business" they do at a given location could vary, explaining the day to day variations in numbers of test results reported. If fewer drive-in or other test locations are being opened on weekend days, with the expected processing and results reporting delays, that could explain the recent Mon-Tue lulls.

There being any significant aspect of the disease process behind the stair-step pattern is therefore questionable, but the long-term changes in rate of increase of new confirmed cases per day are still well-evidenced, and are consistent with the curves now playing out in all different phases in many places.
I know nothing about what covid-19 tests were, or were not, used in MA.

However, around the time the CDC's stranglehold on testing was loosened, there were reports of many different entities developing, and deploying, covid-19 tests. Some even mentioned either specificity and/or sensitivity (University of Washington sticks in my mind for some reason).

Yes, all current tests are PCR-based (not serological)*, but those used by LabCorp, say, are almost certainly not the same as what UMass is using (I have no idea if any UMass campus has developed its own covid-19 test, but you get the idea).

*Telluride - which was a failure - and Iceland (more?) aside
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Old 17th April 2020, 12:13 PM   #2872
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Originally Posted by JeanTate View Post
The third one is up: Best-Case And Worst-Case Coronavirus Forecasts Are Very Far Apart

Some snippets:

"[...] experts expect an average of 263,000 COVID-19-related deaths in 2020, but anywhere between 71,000 and 1.7 million deaths is a reasonable estimate. The researchers believe that only about 12 percent of all COVID-19 infections in the U.S. have been reported, and they donít expect that the daily number of reported cases in New York state ó which was most recently 7,917 ó will drop below 1,000 until around the end of April."

"In the three weeks weíve been tracking the survey, the number of forecasted deaths has increased from 200,000 to 263,000."

"This week, the survey also asked each expert to report the proportion of their responses that comes from experience and intuition rather than from hard models built by themselves or other researchers. On average, 68 percent of each expertís responses are coming from experience and intuition, with the other 32 percent coming from models."
Fifth published by fiveThirtyEight earlier today*: "Experts Think The U.S. COVID-19 Death Toll Will Hit 50,000 By The End Of April"

Some snippets (the survey on which the article is based was "conducted April 13 and 14"):

"The expert consensus is that the U.S. will have reported around 47,000 COVID-19 deaths by May 1, with a 90 percent chance of having between 32,000 and 82,000.

This is very close to the latest forecast from the Institute for Health Metrics and Evaluation at the University of Washington, which projects roughly 51,000 deaths by May 1, with an uncertainty range from about 28,000 to 112,000.
"

Frightening that by today (17 April) the US death toll has blown past 28k, and by tomorrow will almost certainly have exceeded 32k.

"For five weeks, surveyed experts were asked what factors led to the difference between their best-case and worst-case estimates in longer-term death forecasts. The answers have had a common refrain: They canít perfectly predict what stay-at-home orders will be enacted, how long they will last, and how well people will follow those orders. That last issue became particularly salient this week as protesters in Michigan, Ohio and North Carolina organized in opposition to their stateís stay-at-home orders."

I rather doubt that anyone's model could accurately include the effects of those sorts of protests.

"At the time the survey was conducted, three states ó New York, New Jersey and Michigan ó had reported more than 1,000 COVID-19 deaths. As of Thursday, Louisiana, Massachusetts and Illinois have also passed that threshold.

The experts were asked how many states will report more than 1,000 deaths by May 1. They estimated that the most likely number was between eight and 11 states, with a nearly 1 in 3 chance that at least 12 states would report that many deaths.
"

*I skipped the fourth; not very informative I feel. For the record: "Experts Think Weíre Flattening The Coronavirus Curve, But Hospitalizations Havenít Peaked Yet".
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Old 17th April 2020, 12:26 PM   #2873
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Originally Posted by The Atheist View Post
Interesting news off USS Theodore Roosevelt. They're testing the entire crew and after 95% of that, found 600 infections, 60% of which were asymptomatic. That's sure to include a number that were pre-symptomatic, given the long incubation period, but it is more evidence that somewhere around half of all cases are asymptomatic.

https://www.msn.com/en-us/news/us/co...ee/ar-BB12Jojz
This is very critical for policies on epidemic control. This paper on epidemic control strategies;
https://www.medrxiv.org/content/10.1....10.20033738v3
suggests that if > 30% of cases are asymptomatic then a policy based on contact tracing will be ineffective.
This sort of analysis and these figures are important for armchair strategists who think the solution to the pandemic is simple; all that is needed is to carry out contact tracing. In the real world it may be more complicated.
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Old 17th April 2020, 12:45 PM   #2874
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We are also at the point where you have to decide how much more the economy can take. We have much less of a buffer than first world countries.
From Wits university.
South Africa needs to end the lockdown: here’s a blueprint for its replacement
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Old 17th April 2020, 12:52 PM   #2875
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A third of the sailors serving with France's aircraft carrier Charles de Gaulle - 668 out of nearly 2,000 - are infected with coronavirus.

https://www.bbc.com/news/world-europe-52308073

Local news (in Czech) actually had fresher report with more then 1000 infected, that's over 50% of the crew.
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Old 17th April 2020, 01:27 PM   #2876
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Mod InfoThis thread has been closed due to its many duplications with other science and medicine threads about Covid-19. Members are directed to a new, single thread HERE. Members may freely quote from this thread and import discussions here into the new catchall science thread. Thank you.
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