It’s obvious that being in a plastic bubble with only sterilized items and sterilized filtered air entering in is the safest. Your closed windows house still allows air in from the outside … it is theoretically possible for an aerosol or even a fomite to waft in along with outside air.
It is also obvious that the risk for something that is primarily droplet transmission (in which droplets fall quickly under gravity and do not follow airflow) drops off exponentially by 1 to 2 meters and that theoretical aerosol transmission risks are smaller when there is a larger volume of air for the aerosol to be diluted within, such as all of the outside. Volumes (and thus risk reduction) increase exponentially with radius.
Zero risk is simply not possible but the risk drops off rapidly and dramatically with greater distance and greater air volume.
It is also obvious that social contact has benefits, ones that have real impacts on health and impact on morbidity and mortality, as well as quality of life of course. And some social contact from a distance when there is none has the biggest impact.
The discussion is at what distance or environment of the distance does the risk drop off to so very very small that the benefit of the contact outweighs it? Clearly some level of small is small enough measured against some benefit. And some is not so small compared to the benefit accrued.
Sadly I think the answer is that there are so many variables that we really don’t know. WHich is why I suggested the idea of visualising a smoker. Doesn’t help with firm numbers, but does at least give one a starting point.
To some extent these risks are not about individual risk. They play out in the statistical mechanics of the pandemic. If your model says “short contact, no more than 10 feet” and you are happy that the majority of the populace are doing this, you can make more useful predictions about the trajectory of infections. So, rather than worry about precise personal risk assessment, you can view this as playing your part in the community wide statistical model. There will always be random fluctuations. Some people who do stupid things will get lucky, others will find a sudden breeze at just the wrong moment brings with it an unfortunate outcome. Overall it balances, which is what is needed to plan and attack the pandemic.
Had you been in a large living room, 15 feet would probably still have been safe but less so.
I look at the virus as an invading army of guerilla warriors and snipers. They’re not absolutely everywhere, but they’re out there and you don’t know where they are. One wrong move and you could get sniped -and worse, bring the infection back home and snipe others.
The safest place is in the home. Obviously, it’s healthy to go outdoors but that’s safer if you live in a detached home, less so if you live in an apartment complex. Keep your outings to a minimum. Yes, it’s hard.
The public has been badly misinformed or under-informed, and this is an example. Shit, just Google images of the 1918 pandemic and you’ll see people wearing masks, and it’s not just nurses. There are images of nurses in Seattle making masks. They had social distancing. They shut down stores and had stay-at-home orders. They did all this and the electron microscope hadn’t even been invented yet to actually see what a virus looked like. And yet here we are 102 years later not doing shit.
Early in March, a chorale group in Mt. Vernon, Washington, met to rehearse. They were aware of the growing rules about distancing, and any member with sniffles did not attend. They disinfected with hand sanitizers, sat apart from each other, and nobody shook hands or hugged. They rehearsed for two and a half hours, and then went home.
Three days later, 45 of these 60 people came down with COVID-19, and two have died.
Yeah, we need to nail down exactly how large singing groups can be. Is 5 people ok? 10? How about short little diddies? Long Beatles medleys? This is how we’re living for the foreseeable future, people! Don’t kid yourselves!
“Discussing” is one thing, but it sounds like you’re looking for solid answers. There are none. Not yet. We don’t know everything about how this virus is transmitted yet, and even if we did, there are countless variables and plain old luck, good or bad.
(Emphasis mine)
NOBODY knows. I think you’re just going to have to accept that you don’t know. Accept that there is no such thing as truly “safe.” Just try to use your best judgment in deciding what to do and go on with your life.
Pretty much this, as I understand it. Note that I am not a professional in this field, so I am going by various things I have read - and the fact that my wife did her graduate work in virology and she has been tempering my interpretations.
So, my understanding is this: There are two main paths of respiratory transmission in play, droplets and aerosol. The droplets are the main path, and the concentration of these droplets drops off significantly after a meter, mostly from the droplets falling to the ground. Two meters is designed to put you out on the tail of the droplet distribution curve. These droplets can also get on your hands and surfaces where a person may then transfer them to the face: mouth, eyes, nose.
Aerosols are where the virus stays floating in the air via currents, either within floating microdroplets, or just free-floating virus itself; there is data that indicates the virus can survive a while aerosolized.
This physical distancing helps protect against the droplets, and minimizing the duration of any contact helps with the aerosols. This is would be similar to “smelling the cigarette smoke” when you are downwind from a smoker.
Physical distancing is a risk-minimization protocol, not a prevention protocol. Extended exposure, even at a distance, increases that risk. Somebody usually ends up downwind of the other person.
The lockdown will never end. It’s a global police state simply because everyone is allowing it. He who exchanges liberty for security deserves neither.
I understood flatten the curve to mean we try to keep the hospitals close to capacity so we can cycle this virus through as quickly as possible without over running them. Sections of the country that have not been hit too hard yet I would think should open up a little more and allow more infections. Not easy to calculate because of the delay in getting sick but I think it is important to get this thing over and done with as soon as possible.
I’m not looking for perfect answers, but I am trying to inform my judgment. I clearly can’t just trust the government guidelines–those are far too lax. But I also don’t think that I should just rely on what “feels” safe. You talk about “obvious”. I don’t think much is obvious here at all. For example, the discussion of droplets vs aerosols is a really interesting one, and not one I have seen before quite recently–up until a few days ago, everyone seemed pretty sure that droplets, not aerosols, were the problem, and so the media wasn’t making that distinction at all. It turns out it make a huge difference whether or not 2 meters is a meaningful distance.
We have at least 6, maybe 8 more weeks like this. I’d really like to know if it’s safe to stand 25 feet away from my mom in open air, just to have a good look at her. I’d like to develop better judgment–and I can’t do that if every time someone asks a reasonable question they are accused of looking for loopholes and not caring about other people.
I pulled the data from here and plotted the percent increase in the number of cases by day. If that increase is about 20% each day, we would double approximately every 3 to 4 days. There is a lot of noise going back to early March. There is a peak around March 19th of 50%, but since March 22 the rate has been pretty much monotonically decreasing. On March 22 it was 38.8%. Yesterday it was 16.2%. These numbers are driven to a very large degree by the NYC area right now.
I have a couple of thoughts on this data. First, if we can continue to drive down the increase/day we can keep this from doubling every 3 to 4 days . Second, this appears to be coming regionally, which means it will rip through the NYC area, then maybe California and a couple of other places. That will help. We can perhaps keep moving ventilators around to meet demand in localized areas and we won’t need all the ventilators all at once. We might even be able to move patients to areas not slammed at that moment. There is a chance we can keep the medical system from getting overwhelmed. NYC will be a bellweather in a couple of weeks for how that will play out as that is when Cuomo said it will peak there.
This doesn’t mean we can let up on the social distancing and other measures we are taking. But it is a good sign to me that we can deal with the emergencies and hot spots in a given region and perhaps respond appropriately, moving resources as needed.
Is getting a good look at your mom from 25’ away something you consider essential? My mother and I have managed to live our lives on opposite sides of the country.