Welcome back! You’ve been missed, and I hope you stick around!
This set of simulations is why I am not “questioning” jack about social distancing.
This was the main school of thought among experts when you typed this, but in the last 24 hours there has been a major shift toward realizing that asymptomatic carriers ARE major spreaders of the disease. From what I’ve read, this seems mainly to be about folks who will never show symptoms, not so much those who have not yet shown symptoms but will. It is my understanding that this sort of transmission is mainly via breathing nearby (hence all the warnings about six feet/two meter separations).
And…welcome back, Stranger on a Train!
Based on what?
From what I’ve read, based on the distance droplets travel from the human mouth/nose.
These two posts from yesterday link to better explanations than I could give.
We’re not sure yet exactly how this works, but clearly it can be transmitted from person to person without coughing, sneezing, French kissing, or handshaking.
The possibility of transmission via touched surfaces is a complicating factor, but from what I’ve read, that is probably not so important (though it surely is happening when circumstances are just “right”).
Also this:
“These undocumented infections are about half as contagious as documented infections because people are not coughing and sneezing.
Yet they were found to be responsible for about two-thirds of documented infections – because they are so abundant. …
… “We’re seeing just the tip of the iceberg. How much is submerged – five times? Ten times? We can argue about what the exact number is, but if you’re not in a place where you can proactively sample and test, the majority of infections will be undetected.”
Yes, but what cmosdes and others need to understand is that “travel” can happen without coughing or sneezing. Apparently this applies more to this disease than in most others, in part (at least) because it multiplies in the throat in such high numbers (see the Herman study in one of the sources I cited), that the tiny, stray droplets we all sometimes emit when breathing or (perhaps especially) talking to someone take on greater significance.
This surprised me, too, but I believe the experts.
German study, not Herman. Here it is.
First, they don’t seem to know precisely how contagious the disease is. There is one example of a woman who had the disease and out of the 300+ people she interacted with, only one other tested positive. But the problem is we don’t know.
Secondly, even if getting infected were inevitable for everyone, there is still a benefit to delaying it as long as possible.
Finally, if the difference between getting it and not getting it is simply a matter of following certain behaviors, inconvenient as they may be, I’d like to err on the side of not getting sick.
The study that the UK is basing a lot of its policies on estimates about 1.1 to 2.2 million US deaths, depending on how aggressively we respond.
My wife and I loaded up our car and headed from the city to our cabin in the mountains. Mostly because if I’m going to have to work from home, I might as well do it in the woods.
The big problem is that due to lack of testing we do not have good figures. I have seen figures estimating anywhere from 5x to 50x the number of cases that have been proven by tests. This means that the death rate (currently estimated at 1%) will go way down and the reproductive ratio (currently estimated at 2.3) will go way up. But regardless, once about 20% of the people are no longer susceptible the reproductive ratio will go down. And because of the way infectious disease work over time the death rate will decrease as well. So it is a balancing act, we need enough people to get the disease for these factors to become salient while limiting those sick enough to require medical care to what can be handled. For anyone to die because we are out of respirators or hospital beds is not something that should occur here.
So good to see you Stranger. Please stick around.
I live alone and I’m sheltering in place, even though I haven’t been instructed to do that yet. I absolutely do not want to be responsible for spreading this awful virus to anyone.
I also don’t want to be on a ventilator, nor do I want to take one away from someone else that needs one and I don’t want to put a health care worker in the awful position of having to choose who gets it.
This is really a horrible time for all of us. I can do my small part by staying put.
Thank you all for your responses.
And I join the chorus welcoming Stranger back.
Thanks for those links. A friend also sent an article from the New York Times that had similar information. Clearly a dynamic situation.
I didn’t go through the first link. It is a 1.5 hour interview and I’m not prepared to sit through all of that yet.
The NYT article I read suggested aerosol can hang in the air for up to 30 minutes and last on some surfaces for days. This bug is obviously really, really nasty.
Have care with taking anything you see in news regarding specifics of how fast the SARS-CoV-2 virus spreads, how virulent the COVID-19 disease is, or any other supposedly concrete details as being fact. As any epidemiologist will tell you, with a ‘novel’ (e.g. newly introduced) pathogen there is great uncertainty in any of these details which will remain until detailed epidemiological surveys can be conducted, which will be months or even years after the outbreak has subsided. One major problem with trying to make any estimates is that testing, particularly in the US where we decided to develop our own molecular test protocols of still-questionable reliability, has been so sporadic even among symptomatic patients and has been quantitatively extremely limited by the number of text kits available (which is an inexcusable failure given access to the sequenced genome and the wide availability of facilities with RT-PCR assay capability) that there is simply no reliable data-based estimate on the number of infected persons.
The best dynamical system models–which are dependent upon assumptions about transmissibility and appearance of symptoms) have such a wide range of estimates that they are essentially useless in making any detailed projections beyond the reality that it is obvious that the R[SUB]0[/SUB] is much higher than the “2.0 to 2.3” value originally estimated. I did a quick, back-of-the-digital-envelope model last weekend just using the data reported in The Washington Post and JHU (since they seemed more up-to-date than the numbers the CDC was publishing on their website) and was getting an R[SUB]0[/SUB] of at least 4 and maybe higher than 6, which puts it in the same range as mumps, rubella, and the 2002-2004 SARS outbreak, which is unsurprising because the sequenced virus has been found to have 80% to 90% similarity to the original SARS-CoV(-1) virus, and likely the similar pathology and the mode of infection (aerosol vector).
The 2 meter separation threshold is all well and good in an open air environment but inside of a closed building the pathogen may remain active for minutes or even hours while being distributed around by the HVAC system (and no, HEPA filters will not fully contain it, although they will attenuate the distribution of aerosols). This is just a standard public hygiene recommendation that can reasonably be adhered to by people without complete isolation, although it is obviously going to be violated any time you queue up at a grocery line or any essential work function that requires interaction. Which means completely stopping the spread of the virus is impossible (and likely always was), but again, slowing the spread such that hospitals and care facilities are not overwhelmed with a glut of critical patients is still of great value.
Vox:“Why fighting the coronavirus depends on you”
Of course, it also depends on public trust in health officials and public leaders giving fact-based guidance and making the best possible provisions in dealing with the situation. Which has been exactly opposite of what has occurred in this case in many countries including the United States.
Stranger
I find this situation extremely curious. I (as I assume many of you) am pretty darned antisocial in the best of times. I am not “touchy feely.” I go out infrequently, and when I do, I prefer small gatherings. My wife and I occasionally meet w/ 2-4 people, most often in our home or theirs.
I hear what so many of you are saying, but I still find it challenging to accept. Like I said, my employer is requiring that I come in to work 3 days a week, and interact with others in an office environment. Given that, I’m having a hard time accepting that limited social interactions will pose much - if any - added danger to myself or the species.
The challenge of accepting that is not helped by the fact that nearly every single person I have spoken with in person has expressed the opinion that limited social interactions are OK. Combined with the lack of clear guidance (in our area at least), makes it easier to think that small social gatherings are OK.
Just honestly expressing my confusion. I appreciate all of your responses. Not sure where I’m going to come down on every future situation.
I find your skepticism challenging to accept, so I guess we’re even. Except my position has less inherent risk than your skepticism.
Based on what?
IMHO your employer is negligent and grossly irresponsible. I work in a 4000-ish employee building and it’s been mandated that we work from home unless absolutely necessary. And those who must go to work have very strict protocols to follow in order to keep the population density down and to maximize the physical hygiene of the work areas. Basically, my company isn’t fucking around with this. We’ve had people deployed to other parts of the country (we’re in Canada), not even internationally, and they were recalled from their respective business trips ASAP a few days ago, even though they were to be deployed for several more weeks.
What I truly fail to understand is why the empirical evidence visible in places like Italy isn’t sinking in. This isn’t like some monster snowstorm or power outage where, after a week, we can all brag about our impromptu “adventure” camping out in the living room. If we fuck this up, in a few weeks, here in North America where there isn’t a magic barrier, overworked medical personnel are going to be making decisions about which 70-something person gets intubated or not, or gets a ventilator or not or even gets a bed or not.
In various jurisdictions there are discussions about soliciting additional assistance from retired health-care personnel. Notwithstanding the economic fallout or the fact that a shit-load of people won’t have their jobs anymore, we’re not being asked to do anything that difficult - stay in your house unless you have to get necessities, try to keep a distance from others, wash your hands. FFS it’s not like we have to forage for squirrels and wild mushrooms and berries to survive in our crude mud huts while we drink out of puddles.
It’s not that difficult.