Coronavirus: How dangerous a threat?

[Cannavaro]

The article about the controversial study in Heinsberg is now finished:
link
The authors estimate the mortality rate between 0.29% and 0.45%. However, their result is only based on 7 deaths so there is a lot of uncertainty (which is not included in the given confidence interval!)
I made a rough calculation. If you also assume the number of deaths as random and apply an very easy model you get a mortality rate between 0.21% and 0.60%.

There are also some additional interesting results.
It is assumed that a carnival celebration spread the virus and this is confirmed by the data. Interestingly only 19% of the infected people who attended the carnival were asymptomatic whereas 55% of the infected people who didn't attend were asymptomatic.
Does anyone have a good explanation for that? Was the virus load extremely high during the carnival celebration, which was indoors? Was the immune system of the guests unusually weakened?

It is confirmed that the infection risk increases if one member of the household is infected. Surprisingly this risk increases if the infected person is a child. However this result is not significant. There are two few cases to get reliable results.
This would be in agreement with the study of Christian Dorsten (link), which finds similar virus concentration in children and adults but was critized as Jagartrott wrote.

Another study (https://t.co/XfpT7Iu3ym?amp=1) finds that children have a significantly lower risk to get an infection.

So maybe children are as infectious as adults, but fewer get infected and so there are not the main source of spread.

 

[Merckx index]

The article about the controversial study in Heinsberg is now finished:
link

Thanks for that link. Some very interesting stuff.

They tested for both IgA (antibodies found predominantly in mucous membranes, such as the respiratory system) and IgG (antibodies found in the blood). The IgG prevalence was used as a measure of seropositivity. They had to make several corrections:

• The initial IgG prevalence was 13.6%. This was corrected for specificity (99.1%, i.e., 0.9% false positives) and sensitivity (90.9%, 9.1% false negatives). The corrected figure became 14.11%, or a total of 130 subjects out of 919 in the sample studied [Note in passing: the IgA specificity was much lower, 91.2%]
• A total of 33 subjects (of 919 total) tested positive for the virus by PCR. An additional 22 reported on the questionnaire that they had tested positive in the past. The researchers don’t say this (they definitely should have), but 13 of these 55 subjects did not test positive for IgG (some might have tested too recently to have developed antibodies, while others might have been false negatives for antibodies). So these 13 were added to the 130 seropositives, for a total of 143, or 15.56% (the researchers report 15.53%, because they perform the calculation slightly differently). When you multiply this by the total population of the town, 12,597, you get 1956 projected seropositives. When you divided the latter by seven deaths, you get a mortality rate of 0.36%
• As noted above, 22 people reported testing positive in the past. This represents 2.39% of the 919 people in the sample. However, the official positive rate in the past was 3.08%, based on 388 confirmed cases in the town of 12,597. The authors conclude from this that positives in the past were underrepresented in the sample—perhaps because people who knew they had been infected and recovered weren’t particularly motivated to have an antibody test. It wouldn’t tell them something they didn’t already know. In any case, the authors applied this correction to their previous conclusions, resulting in a lower estimate of the mortality rate, 0.28%. But they don't emphasize this much.
• Some of the study participants were in the same household as others. The authors encouraged this, because they wanted to assess the risk of someone living in the same house with an infected person. But this also introduces bias in the sample, because people living in the same household with an infected person would be expected to be at enhanced risk of becoming infected. The authors say they corrected for this, but again, this is not something they emphasize in their final conclusions. As far as I can tell, they only use this clustering correction to adjust confidence limits.

As far as the risk, itself, the researchers found there was no change in risk related to household size. That is, the risk of infection was the same if one were living with one, two or three other people. If one lived in a household with one known infected person, however, there was an increased risk. If there was one infected person and one other person, the risk for the other person now was increased from 15.5% (the general risk for the population) to 43.5%. For three people, the risk for the other two increased to 35.7%. For four people, the risk to the other three increased to 18.3%. So the larger the household, the less the increased risk to each person from one infected person. I’d guess that follows from probably a larger total living space, and less interaction between any two people.

Interestingly only 19% of the infected people who attended the carnival were asymptomatic whereas 55% of the infected people who didn't attend were asymptomatic.
Does anyone have a good explanation for that? Was the virus load extremely high during the carnival celebration, which was indoors? Was the immune system of the guests unusually weakened?

Here's what the authors suggest:

At this point, the reason for the association with celebrating carnival remains speculative. Thus far, we could not identify confounding factors that would explain the observed difference. However, it is well established that the rate of particle emission and superemission during human speech increases with voice loudness25. Because of loud voices and singing in close proximity are common in carnival events, it is reasonable to speculate that a higher viral load at the time of infection caused the higher intensity of symptoms and thus more severe clinical courses of the infection.

 

[Cannavaro]

As noted above, 22 people reported testing positive in the past. This represents 2.39% of the 919 people in the sample. However, the official positive rate in the past was 3.08%, based on 388 confirmed cases in the town of 12,597. The authors conclude from this that positives in the past were underrepresented in the sample—perhaps because people who knew they had been infected and recovered weren’t particularly motivated to have an antibody test. It wouldn’t tell them something they didn’t already know. In any case, the authors applied this correction to their previous conclusions, resulting in a lower estimate of the mortality rate, 0.28%. But they don't emphasize this much.

I have to say that the authors are doing here something which is at best very! naive and at worst manipulating (I studied statistics). What they are trying to do here is estimating a sampling bias. But 22 observations are far to less to do this. In fact you get confidence intervals ranging from 0.86 to 2 for the factor they say is 1.29. So you can not even say if there is under or overreporting! Of course they do not take this variability into account. Furthermore they apply this correction to people who do not even have symptoms! This makes it ridiculous. Their article would be much better if the authors skip this part completely.

 

[Merckx index]

I have to say that the authors are doing here something which is at best very! naive and at worst manipulating (I studied statistics). What they are trying to do here is estimating a sampling bias. But 22 observations are far to less to do this. In fact you get confidence intervals ranging from 0.86 to 2 for the factor they say is 1.29. So you can not even say if there is under or overreporting! Of course they do not take this variability into account. Furthermore they apply this correction to people who do not even have symptoms! This makes it ridiculous. Their article would be much better if the authors skip this part completely.

Yes, i realized the problem later. The 22 positives indicate that people who test positive are under-represented, but the authors are assuming that people who are positive, but don't test positive--who their results show are by far the majority of cases--are also under-represented. Not only is this unproven, but if one assumes the reason that people who test positive for the virus are under-represented is because they are less inclined to have an Ab test, it would follow that people who are positive but don't get tested and thus never know it, would not have any reason not to get tested for Abs.

Of course, it's possible that the under-representation is due to some other reason that might apply to all who were originally positive. But in the absence of knowing this, all the authors are legitimately allowed to do is add the number of positives that would have resulted without under-representation, which increases the total positives by about 4.5%, rather than by 29%. This has very little effect on the mortality rate, decreasing it from 0.36% to 0.34-.35%.

Another extremely important point is that the authors claim only about 22% of the subjects were asymptomatic. It took a little while for this to sink in for me. They're saying most of the subjects who tested positive for antibodies (plus the PCR positives that were seronegative) experienced one or more symptoms often associated with C19. IOW, while about 80% of the seropositives never tested positive for the virus, most of them reported symptoms. So it seems that a majority of the seropositives were symptomatic, yet never got tested.

Why? Symptoms are not a clear-cut indicator of C19. The authors report that even uninfected people reported some. But they generally reported no more than 1-2 of a total of fifteen examined, while the infected cohort averaged 3-4, with 56% reporting 3 or more.. The difference was significant at the p < 0.001 level.

This has enormous implications if applicable to other locales. It suggests that the reason there are so many silent positives--some researchers estimate they may be ten times the number of confirmed cases--is not because these people are really asymptomatic, but because they don't get tested when they should. Whether this is because they try to and can't, or because they don't think the symptoms are serious enough to likely indicate they're positive, or just don't want to, it suggests that identifying and testing these people is maybe not as difficult a challenge as it has been made out to be. While there is no clear-cut line separating infected from uninfected, there is enough separation to use as a basis for targeting. Based on this population, at least, more than half the silent positives could have been identified by simply testing everyone reporting three or more symptoms--with no false positives, i.e., no people who were actually negative would have been targeted.

 

[Jagartrott]

From StatBel (but the same trend is also visible in EuroMomo statistics for the EU):
Between 16 March and 19 April 8.329 people aged 85 or more have died in Belgium - the average over that period is about 4500. That means excess deaths of about +80%. For 75-84, this is +60%, 65-75 it is +50%, 45-64 only +13%, 25-44 no difference, and below 25 there are less deaths than normal. This reinforces what I said earlier about normal life (especially through traffic accidents) being more dangerous for children than covid-19.

You could also say the younger generations are preserving the older ones at the moment, but the question is whether this is something that can be sustained for a long time. After all, the longer term harmful (secondary) effects will be on exactly those younger generations (unemployment, financial issues, potentially rising inequality, anxiety, etc.). Also, I believe statistics such as these demonstrate that strategies between countries should differ, depending on their demographics. For countries in Africa with weak economies and only a small fraction of 65+ people, installing the 'western' lock-downs will probably cause a lot more damage than more targeted measures.

 

[Jagartrott]

Something that may be useful in the longer run:

Sports

Sports news, analysis, rumors, statistics, predictions and roster moves around the NFL, NBA, MLB, NHL and more.

heavy.com

 

[djpbaltimore]

This reinforces what I said earlier about normal life (especially through traffic accidents) being more dangerous for children than covid-19.

You could also say the younger generations are preserving the older ones at the moment, but the question is whether this is something that can be sustained for a long time. After all, the longer term harmful (secondary) effects will be on exactly those younger generations (unemployment, financial issues, potentially rising inequality, anxiety, etc.). Also, I believe statistics such as these demonstrate that strategies between countries should differ, depending on their demographics. For countries in Africa with weak economies and only a small fraction of 65+ people, installing the 'western' lock-downs will probably cause a lot more damage than more targeted measures.

It better be because I don't see any way to steer out of our present course. Obviously, different countries may have different solutions. The new argument here in the USA for opening businesses is that, like during WWII, we are going to have to make sacrifices to preserve the American way of life. Based on the numbers below, I don't think people are willing to do inessential things in order to preserve businesses and jobs. Whether that choice is altruistic or rooted in self preservation, there is no easy way to reset back to normalcy without substantially fixing the virus problem. You could argue that this is an irrational public position based on the empirical data, but I don't see how that changes in the short term. FWIW, the only person who I know who has died was in their 50s.

https://twitter.com/x/status/1257643424766926849

View: https://twitter.com/suzannelynch1/status/1257643424766926849

 

[Koronin]

Here's some news on one of hopeful vaccines:

https://finance.yahoo.com/news/pfizer-biontech-set-begin-u-104500028.html?ncid=facebook_yahoonewsf_akfmevaatca

 

[djpbaltimore]

Potential point of care testing. The swab and PCR test is not scaleable to the level needed to test and trace in the USA. Testing has been relatively flat for over a month. We need to emphasize quicker and less labor intensive tests that can be done outside of research laboratories, even if they are probably less accurate.

https://twitter.com/x/status/1257691557160943619

View: https://twitter.com/zhangf/status/1257691557160943619

 

[Koronin]

Potential point of care testing. The swab and PCR test is not scaleable to the level needed to test and trace in the USA. Testing has been relatively flat for over a month. We need to emphasize quicker and less labor intensive tests that can be done outside of research laboratories, even if they are probably less accurate.

https://twitter.com/x/status/1257691557160943619

View: https://twitter.com/zhangf/status/1257691557160943619

I've heard that some of the university labs around the country are working on blood tests to detect the virus. That would allow for more testing and faster results if they can get it work.

 

[yaco]

Emirates when flying from Dubai use a pin *** test on prospective passengers in which results are available in ten minutes - I am unsure whether it's a COVID test or an Anti-body test - With further development this could be the way to get air traffic moving again.

 

[BlueRoads]

What do you guys think of masks?
I thought they were okay before I had to wear them. Putting it on for 10 minutes, okay, but after 2 minutes I start to feel so bad. I feel like I don't get any air anymore. I thought it was because I had the wrong masks (selfmade ), but it does not really matter. Am I being overly sensitive? Or do you feel the same?
For now it's okay, but if this really is supposed to be the new normal and I have to wear it for hours I feel I will go crazy - or just fall on the floor. I read a lot of people in Asia are wearing them for hours at work - whoo.
Okay, I know, I'm overly sensitive to pain, so it might be the same here. Or do you just get used to it?

@yaco: If it's an anti-body test that sounds like a dangerous way to go to me. It's discriminating + it will make people try to catch the virus. (Well, not if Emirates alone do it, but if other companys and institutions follow.)

 

[Jagartrott]

My only experience with a face mask was in October in Beijing, when a colleague had given me one against PM pollution. I wore it one day with bad air quality during the 20 minute walk to university, and my ears already felt like they were being torn off. I don't think it is ever a comfortable experience, but I guess you can get used to it, and solutions exist to make the bands cause less friction. The biggest challenge is not fiddling with it the whole time.

 

[djpbaltimore]

I would recommend trying different types as that can make a difference. A mask is required for work in our animal facility, so I have gotten used to wearing them for a long duration before that became the norm. It does take a little getting used to, especially repressing the urge to scratch itches on your face. The one I like has an elastic band that goes around the back of the head. The front is a cup-like piece that goes over the nose and mouth. It looks a little like Bane.

Besides the businesses where I live, a mask is now required on public transit, but often people will take them off or pull them down once they board. It is something that works better in principle than in practice. But I understand the rationale.

 

[Keram]

Try it on bike guys I now only put it on when I meet someone or in municipality so basically I wear it maybe 5% of my rides. It is pretty uncomfortable but I can breath in it even when doing sport. Now I use some sport "scarf" or I dont know how can I tell it in english but one time I used regular face mask and my ears were in real pain with putting it on and off.

 

[Koronin]

For another treatment look to the clinic trials starting in June from Regeneron. They have a lab created antibody treatment they will start human tests in June. This is similar to their highly successful treatment for Ebola. IF this works as well as that one, it's possible once there is enough of it that things can start returning to closer to normal.

 

[jmdirt]

What do you guys think of masks?
I thought they were okay before I had to wear them. Putting it on for 10 minutes, okay, but after 2 minutes I start to feel so bad. I feel like I don't get any air anymore. I thought it was because I had the wrong masks (selfmade ), but it does not really matter. Am I being overly sensitive? Or do you feel the same?
For now it's okay, but if this really is supposed to be the new normal and I have to wear it for hours I feel I will go crazy - or just fall on the floor. I read a lot of people in Asia are wearing them for hours at work - whoo.
Okay, I know, I'm overly sensitive to pain, so it might be the same here. Or do you just get used to it?

@yaco: If it's an anti-body test that sounds like a dangerous way to go to me. It's discriminating + it will make people try to catch the virus. (Well, not if Emirates alone do it, but if other companys and institutions follow.)

I started wearing a mask at the supermarket around the beginning of April (the only public place I go). Its a little funky at first, but after I got used to it and got the straps figured out, its tolerable for an hour plus for me. I have a home made mask that a neighbor made that is OK, and a buff style tube that I modified which isn't quite as good but usable. The most annoying thing for me is fogging my glasses.

Two thoughts about your situation: 1) be sure that you have a little 'void' space between your nose/mouth and the mask , 2) either get wider ear straps or change to around the head/neck straps. I saw a lady with an ear loop style but she had it looped through the band that was holding her hair back.

Can you order your groceries online, and pick them up? That's what my mom has been doing and it has worked well for her. I can't remember what your work/school situation is.

As I've discussed, I feel like I can get through a hour of discomfort if it can potentially help someone else. If I have to start working from work again and that requires a mask, I will definitely make or purchase something suitable for all day use.

I'd say that I have a very high physical pain tolerance so that is an advantage I suppose.

 

[Koronin]

I started wearing a mask at the supermarket around the beginning of April (the only public place I go). Its a little funky at first, but after I got used to it and got the straps figured out, its tolerable for an hour plus for me. I have a home made mask that a neighbor made that is OK, and a buff style tube that I modified which isn't quite as good but usable. The most annoying thing for me is fogging my glasses.

Two thoughts about your situation: 1) be sure that you have a little 'void' space between your nose/mouth and the mask , 2) either get wider ear straps or change to around the head/neck straps. I saw a lady with an ear loop style but she had it looped through the band that was holding her hair back.

Can you order your groceries online, and pick them up? That's what my mom has been doing and it has worked well for her. I can't remember what your work/school situation is.

As I've discussed, I feel like I can get through a hour of discomfort if it can potentially help someone else. If I have to start working from work again and that requires a mask, I will definitely make or purchase something suitable for all day use.

I'd say that I have a very high physical pain tolerance so that is an advantage I suppose.

My issue with the masks is the elastic starts bothering my ears after about 45 minutes to an hour. Starting in two weeks I'll be back working my main job in stores which at times is over an hour at a time. I'm seriously considering digging out my cycling winter face covering thing that's a tube thing that goes over nose and mouth. Just hope no one gets too unhappy that it says Movistar on it. LOL

 

[Unchained]

San Diego notes:
Masks are required.
Saw a group of 4or 5 pacing up a hill..all keeping good speed and cadence..a half a bike length between each rider..all of them wearing serious looking masks..!!
many of our coffee spots including Starbucks w drive through suddenly reopened..
And now for the discussion about beer..ie..virus in the beer..not on the exterior of the can exclusively..but in the brew..?
listened to The Daily yesterday..a woman working in the South Dakota Smithfield processing plant..her story had me tearing up..but that aside..if sick people cough on pork chops or chicken cutlets..is it still there after,,packaging..travel..store stocking process?
I am rethinking my love for Sushi and Steak tar tar..oysters..
I am getting worried and depressed at the same time!!!

 

[Merckx index]

Just hope no one gets too unhappy that it says Movistar on it. LOL

Paste a picture of Valverde on it. That will scare everyone well past the social distance limit.

And now for the discussion about beer..ie..virus in the beer..not on the exterior of the can exclusively..but in the brew..?

You've been indoors too long, good that you can get out now.

listened to The Daily yesterday..a woman working in the South Dakota Smithfield processing plant..her story had me tearing up..but that aside..if sick people cough on pork chops or chicken cutlets..is it still there after,,packaging..travel..store stocking process?

I'm not clear on what happens to the meat after that. If it got exposed to the virus, was then immediately covered with plastic, and kept cold (as it presumably would be, better be) till being sold, then, it's possible some of the virus would still be infectious. The virus is generally going to stay intact longer in cooler temperatures, though there could be something in meat that messes it up, too. But virus on plastic wrap, in the cold, could definitely be a problem. One study i saw claimed that infectious virus could be found on plastic several days later, and if it were kept cold, more of it would persist. i don't know how many days would pass between packaging and the item sold to a customer, but if it were within a week, I'd think there would be reason for concern.

Of course you want to make like a raccoon, and wash all your food before eating it. But you should probably wash the packaging, too, before disposing of it.

 

[Oldermanish]

Paste a picture of Valverde on it. That will scare everyone well past the social distance limit.



You've been indoors too long, good that you can get out now.



I'm not clear on what happens to the meat after that. If it got exposed to the virus, was then immediately covered with plastic, and kept cold (as it presumably would be, better be) till being sold, then, it's possible some of the virus would still be infectious. The virus is generally going to stay intact longer in cooler temperatures, though there could be something in meat that messes it up, too. But virus on plastic wrap, in the cold, could definitely be a problem. One study i saw claimed that infectious virus could be found on plastic several days later, and if it were kept cold, more of it would persist. i don't know how many days would pass between packaging and the item sold to a customer, but if it were within a week, I'd think there would be reason for concern.

Of course you want to make like a raccoon, and wash all your food before eating it. But you should probably wash the packaging, too, before disposing of it.

Yeah. Wash it all. Wifey here is a chef and has always washed all foods prior to prepping. Cooked foods will cook most hazards away but residual contamination on prep areas, utensils and serving items are customary transmission vehicles. Basically: put fire to it and then eat it no matter what it is if you're paranoid. Otherwise presume that you need to wash everything you put in, on or in the environment around your body for awhile.

 

[Jagartrott]

Secondary effects... I already spoke about malaria, this article is about tuberculosis. I think covid response is demonstrating a very 'first world viewpoint'.

Millions predicted to develop tuberculosis as result of Covid-19 lockdown
https://www.theguardian.com/global-deve ... 9-lockdown

“I have to say we look from the TB community in a sort of puzzled way because TB has been around for thousands of years,” Ditiu said. “For 100 years we have had a vaccine and we have two or three potential vaccines in the pipeline. We need around half a billion [people] to get the vaccine by 2027 and we look in amazement on a disease that … is 120 days old and it has 100 vaccine candidates in the pipeline. So I think this world, sorry for my French, is really *** up,” she said.

 

[Jagartrott]

How do they get to 4-5% immunity based on these results? Also, with only a couple of hundreds of covid-deaths (let's say 500), assuming a mortality of 0.5%, you would get to c. 100.000 infections or about 1% of the population.

The Guardian:
Immunity to Covid-19 is only building very slowly in the Czech Republic and probably does not cover more than 4-5% of the population, the country’s health ministry has said.
The preliminary figures came from a mass testing for antibodies that started in April, the ministry added.
According to figures compiled by John Hopkins University, there have been 7,896 confirmed cases and 257 Covid-19 deaths so far in Czech Republic. The country, which has a population of 10.7 million, was one of the swiftest in Europe to impose curbs on travel and border crossings and shut most shops and restaurants in March.
The preliminary results from the study found immunity levels were likely lower in the two biggest cities of Prague and Brno. Overall, it found 107 positive cases after testing 26,549, making it one of the largest studies in Europe. The study estimated the number of people infected by the virus but not showing symptoms could range from 27-38%.

 

[BlueRoads]

Thanks for all your replies regarding masks!

 

[yaco]

What do you guys think of masks?
I thought they were okay before I had to wear them. Putting it on for 10 minutes, okay, but after 2 minutes I start to feel so bad. I feel like I don't get any air anymore. I thought it was because I had the wrong masks (selfmade ), but it does not really matter. Am I being overly sensitive? Or do you feel the same?
For now it's okay, but if this really is supposed to be the new normal and I have to wear it for hours I feel I will go crazy - or just fall on the floor. I read a lot of people in Asia are wearing them for hours at work - whoo.
Okay, I know, I'm overly sensitive to pain, so it might be the same here. Or do you just get used to it?

@yaco: If it's an anti-body test that sounds like a dangerous way to go to me. It's discriminating + it will make people try to catch the virus. (Well, not if Emirates alone do it, but if other companys and institutions follow.)

Who would try to catch the virus ? And how would you catch the virus ? The Emirates trial is a work-around to get international travel working until a vaccine is found.