quarterdime

I believe that "asymptomatic" refers to an infected individual who will never get symptoms. "Presymptomatic" means the individual has no symptoms, but will develop them later.

As far as presymptomatic transmission, this is a good case study from Germany: https://wwwnc.cdc.gov/eid/article/27/4/20-4576_article. A 59 case cluster in which little/no asymptomatic transmission was observed, but 75% of transmission was presymptomatic.

Another interesting paper, also out of Germany covering 400k individuals, 25k infections: https://science.sciencemag.org/content/373/6551/eabi5273. I can't write a summary better than the one in the paper: The role that individuals with asymptomatic or mildly symptomatic severe acute respiratory syndrome coronavirus 2 have in transmission of the virus is not well understood. Jones et al. investigated viral load in patients, comparing those showing few, if any, symptoms with hospitalized cases. Approximately 400,000 individuals, mostly from Berlin, were tested from February 2020 to March 2021 and about 6% tested positive. Of the 25,381 positive subjects, about 8% showed very high viral loads. People became infectious within 2 days of infection, and in hospitalized individuals, about 4 days elapsed from the start of virus shedding to the time of peak viral load, which occurred 1 to 3 days before the onset of symptoms. Overall, viral load was highly variable, but was about 10-fold higher in persons infected with the B.1.1.7 variant. Children had slightly lower viral loads than adults, although this difference may not be clinically significant.

The second paper is a bit dense, but there is a great discussion at https://www.youtube.com/watch?v=p4AR7qPxz_Q, with discussion of this paper beginning maybe 47:00. 1:14:08 beings a discussion about how a large number of cases might be caused by a small number of individuals. Interestingly, these individuals are not necessarily the same as those who go on to be seriously ill, hospitalized, or die.

In practice, the difference between presymptomatic and asymptomatic makes little difference. The key is that we have ample evidence that an infected person can infect others while they do not have symptoms.

"Since the deadliest virus mutations kill their hosts, weaker virus mutations can spread (without killing their hosts) more quickly."

The problem with the SARS-COV2 virus is that infected individuals are infected before they're symptomatic, let alone dead. Thus there is no evolutionary pressure that would make this virus less lethal, as is the case for viruses that kill their hosts early in the course of infection.

Yeah, I think the lesson was indeed pretty well learned. My initial comment was off though--I said that the banks hold a lot of this debt. I reread and saw that reddit poster claimed that the banks hold very little and pass it down the line to funds. Maybe they hold little enough that they will be fine. Maybe they hold enough that they will need a bailout. Either way they win. I agree with you. Their success with mortgage backed securities last time appears to have inspired a sequel.

I think this market has been headed for collapse since well before coronavirus. https://www.propublica.org/article/whistleblower-wall-street...

The industry is reading off the exact same script as 2008 but with all sorts of increasingly silly financial instruments based off commercial real estate. Because of course commercial real estate is different.

This is crazy and has been going on for a while. I fear this is every bit as big as 2008. A lot of wealth is about to evaporate. A lot of it from the middle class. I notice that the market is UP and Americans are killing one another in the streets. What is this going to look like when unemployment hits 30%? Our whole economy runs on credit. At some point the banks are going to get squeezed by this. Nobody is going to sign a lease on commercial property in 2020. Businesses need to borrow money. The fed is trying to print money fast enough to shrink the problem, but I do not think there is any way for them to stay ahead.

Totally unrelated question. That guy Jared Kushner: does anyone remember what industry he's in?

I cannot believe that with over 500 bewildered comments yours is the only one to make this obvious connection. I have a difficult time forming any other conclusion than yours. I agree that an executive order would be a direct response to TikTok users trolling him at Tulsa.

It will be interesting to see how this plays out. These TikTok users already won round 1 (Tulsa) and this would mean war.

As a long time lurker I finally had to create an account to reply to you. Boeing was indeed extremely large and profitable. Building such a successful enterprise came from lifetimes of work with dedication to excellence in engineering, manufacturing, safety, etc. Unfortunately we are seeing that a decade or so of attacking these values is enough to destroy even a giant. I do not believe that we are seeing just a streak of bad luck. Off the top of my head, let's review a few of Boeing's recent big projects.

787 - Historically over budget and delayed. Failed static wing deflection test, showing how much we can trust the FEA work. In cockpit battery fires led to a historic worldwide grounding of Boeing commercial aircraft. A NTSB report blamed (in part) Boeing engineers for not considering worst case scenario for a lithium battery in a cockpit compartment that contained no fire suppression system. A grounding like the one OP linked is not unprecedented, it is of the 'the plane is grounded until it passes an inspection' type. The battery fire issue led to a 'all planes are grounded until Boeing has a fix.' I believe that this is the first time that Boeing had an aircraft grounded in this way. I believe it was 3 months for Boeing to have an FAA approved fix. Incidentally the 'fix' was a heavy duty sheet metal box around the battery, with a vent to outside the aircraft. I suppose time will tell how reliable a fix this is. Finally there have been issues with debris being left in fuel tanks, metal shavings in wire bundles, etc. Allegedly in aircraft delivered to customers.

737 MAX - A half-baked software bodge has left hundreds dead and all these aircraft grounded worldwide. This is the second time Boeing had a commercial aircraft grounded worldwide with no end in sight. As with the 787 there are issues with debris being found in "complete" aircraft, with foreign object material being found in fuel tanks AFTER the aircraft has left assembly and passed inspection.

KC-46A (Air Force Refueling Tanker) - Years late, over a $1B over budget. Egg on face issues like not having the (required) FAA approval for fuel pods and drogue system. Repeated issues where Air Force refused delivery because of... debris in fuel tanks.

Starliner Crew Capsule - multiple critical software errors that meant the capsule never docked with the ISS and was nearly lost.

There are some common threads here. Bad software for 737 MAX and Dreamliner. Foreign object material ending up in wings and fuel tanks over and over.

Finally there is good reading to be had about quality issues in assembly, parts being rejected as defective and then "disappearing." Whistleblowers are reporting that the "disappeared" defective parts such as tail assemblies are ending up on aircraft and being delivered to customers. It seems there is pressure from management to sacrifice safety for profit, pressure to approve designs (thanks to some really good lobbying, Boeing essentially gets to approve its own designs with minimal FAA oversight), pressure to keep you mouth shut about safety concerns (and retaliation if you don't).

These are not signs of a healthy company. By now I think that Boeing has slid into "all-around shitty." The above is my best recollection of news stories from years of watching Boeing, if I have made a mistake then I am happy for any corrections. Let me know if you would like links to any of the particular stories or believe that a [citation needed] is in order.