Whether the herd immunity is a good idea surely depends on a few factors, such as the fatality rate and how quickly vaccines become available.  Even the fatality rate is hard to determine.  In the case of COVID, it's hard to determine whether the virus was the direct cause of death or not, as the 70+ age group makes up the vast majority of deaths.  Also, the capability of the health care system is important.

I think the Swedes were far too optimistic about when herd immunity would be achieved, but it doesn't mean that everything they did was wrong.  A lot of countries are now pretty much doing what Sweden did in March: no general lockdowns.

As I've said before, we wont know what the best strategy should have been until the dust settles and the numbers are in.  Then we can look at unusual death rates regardless of cause, and Sweden might still do far, far better than many countries that did lock down.  It's premature to draw conclusions now, and it's even become a political issue, in particular in the US.  It's worrying that social media companies delete or ban people for questioning such things as how well face masks work, as if everything is black and white.  That some are so loud in their role as keepers of the Truth is itself a sign that there is much yet to be researched.  I also think that there will be no simple answer to "best strategy".  What works well in one country, might not work as well in different countries, and vice versa.

Herd immunity (sans vaccine) could be a few million deaths and overwhelm the hospital vaccine (at least here, where it was already overwhelmed in the early months of the pandemic.)
https://time.com/5900024/covid-19-herd- ... dangerous/
Time did a new article on Sweden in which they gave Sweden some praise on their new approach
https://time.com/5901352/sweden-local-lockdowns/
And something on the new UK policy for the vaccine trials which allows people to get infected via spray
https://time.com/5901961/challenge-trials-uk/

I wanted to go back and make a better illustration of what midtskogen said earlier about the de minimis role of politics compared to demographics and culture on the pandemic. Here I animate a plot of deaths per capita against population density for all 50 states in the US, with states colored red or blue according to the political affiliation of their governors. 



Conclusions: as we already saw, the correlation between deaths per capita and density is extremely robust. I think we intuitively expect it, and the data verify it. But with regards to politics, if we hypothesized that the political affiliation of the state governors would correlate to the effectiveness of their pandemic response, I think the data thus far refute that. Finally, it shows how the virus spreads over time from high population density to low density (also from the coastal states to the interior, which is why we see the lag between the blue line and the red line).

That's interesting Wat, but how do you explain the low infection rate of New York (around 1%) vs other states?  Even in NYC, while there were pockets of higher infection rates they have quickly gone down again (see Cuomo videos); the response is far better than a state like Florida (for example) which has an infection rate I can't even comprehend.  Way more people wear masks here than in those antiscience red states.

Wat also want to get your input on this interesting read from the LA times about the low rates that have been maintained in SF throughout.




Of the 20 most populous cities in the U.S., San Francisco has the lowest death rate per capita from COVID-19. If the entire country had followed the city’s approach, says a 
@UCSF
 doctor, there would be just 50,000 dead from the pandemic instead of 220,000+

Experts credit San Francisco’s success to a long partnership between public health officers and universities, most notably during the AIDS crisis. San Francisco is not monolithic, but its residents largely followed health guidelines.

The tech industry played a role too. Companies ordered their employees to work from home two weeks before San Francisco and other Bay Area counties shut down, Signaling to the rest of the region that they were taking the coronavirus seriously.

Mayor London Breed's approach to the pandemic has largely shaped the city's success.
She decided early to prioritize saving lives over the economy and hasn't hesitated to scold residents who break the rules.

San Francisco’s public health director Dr. Grant Colfax became known for his grim warnings of how the virus could spin out of control. 
He was early in tipping off the mayor to COVID-19's potential to devastate the city.

SF police also helped enforce the health rules. When long lines sprung up, officers arrived to ensure people were distancing and wearing masks. Police patrolled the parks on the weekends and handed out masks.

That's interesting Wat, but how do you explain the low infection rate of New York (around 1%) vs other states?

I don't think there's any mystery. Look at how much testing and tracing New York is doing. More testing of course means a lower positivity rate for a given number of true infections, but more importantly it also means they have so much data coming in so rapidly that they can tailor the response to the neighborhood level, so every time a new cluster pops up they can stamp it back down quickly and without having to impose restrictions on entire counties or even the entire state.

This is very similar to how China and other countries with SARS experience handle the virus. Testing, tracing, public health interventions, and public education are the best ways to manage the spread of a virus until vaccines are available. And testing is such an important part of that, because you can't solve a problem as easily if you can't narrow down where the problem actually is or how it is changing over time. The whole exercise has to be data driven.

Aside, I think the federal response has largely failed in this regard. It rather seems that their strategy has shifted to not trying to control the spread. They have favored leaving most decisions to the states, which I agree with, but they still have very important roles to play. At the very least they could do a better job on public education, even by something as simple as saying "yes this virus has proven to be a serious threat and everyone can do their part to reduce spread even just by wearing masks in public areas". But instead masks have become politicized because supposedly we can't tell people what to do even when it's for protecting public health. Nevermind that we have state and federal seat belt laws and drunk driving laws...

Wat also want to get your input on this interesting read from the LA times about the low rates that have been maintained in SF throughout.

The timeliness of public health interventions is important, especially during the early phase of exponential growth where things can get out of control so fast. Every day of delay literally costs exponentially more lives. In the above plot we see that deaths per capita correlates extremely strongly to population density, but much of the scatter above and below the best fit line may be related to how soon measures were implemented. Of course the pandemic is ongoing, so continued effectiveness of measures will determine how things go from here.

Washington State currently lies below the trend line, and I think that's because the governor acted very quickly under the guidance of local health officials and university modelling. We were also one of the first states to enforce a statewide mask mandate in public spaces. New York on the other hand lies above the trend line, and I think it is not controversial to say that they could have shut things down earlier (though hindsight is of course 20/20.) But look, both states are 'blue states'. So did party affiliation matter? The plot of deaths/capita vs. density shows that red and blue states are fairly equally clustered around the same trend line, so at the moment I do not agree that state level partisan politics made much difference. 

I say this as dispassionately as possible, because there has been so much passionate debate about politics with the pandemic, and I prefer to see what the data actually show. I remember suggestions early on to not give federal assistance to hard hit 'blue states', and now I see people suggesting it is a 'red state' problem. (Those sorts of claims were an inspiration for making that plot.) I think both perspectives are wrongly motivated, and symptoms of a much deeper problem in this country.

At the very least they could do a better job on public education, even by something as simple as saying "yes this virus has proven to be a serious threat and everyone can do their part to reduce spread even just by wearing masks in public areas". But instead masks have become politicized because supposedly we can't tell people what to do even when it's for protecting public health.

But masks are not the first line of defense, nor the second, and simply saying saying that the least people can do is to wear mask could have the effect that people who do wear a mask think they're doing their part if they do so.  And considering how many people use the masks by repeatedly touching their faces, reuse and not washing, it might be harmful if not stressing where masks are appropriate, like on crowded public transport.  The most effective way to stop the virus is to educate people to stay at home if sick, wash hands (anti-bacterial stuff is less good but better than nothing) and to limit their social close contacts, i.e. situations when they're close to other people for several minutes, besides making free testing and tracing easily available.  So stay at home if sick, work from home if possible, don't go to large parties, crowded pubs, church congregations, crowded concerts, whatever which isn't really necessary.  Yes, it's disappointing if you had planned a big wedding, so either postpone the party or make it relatively small and outdoors.  But buying your groceries in a non-crowded store is fine.  Common sense is fine.  It seems to me that masks have become political and symbolical.  It's like fixing something with duct tape.  Is it showing that you're taking things seriously by doing something, or is it a sign that you don't really care about doing things properly?  I mean, masks help in certain situations, so seeing masks then means that you've failed in avoiding those situations.

A good public education for limiting the spread of the virus will, and I think has, emphasized all of those things, and reducing the size of social gatherings is an enforced law and one of the first measures most states took to combat the spread. So I do not think we ever considered masks the first line of defense. The first line of defense was reducing many functions of society and then reopening them according to how essential they are vs. how much risk they impose. Masks are rather an additional line of defense for when close contact or shared indoor space cannot be avoided, such as workers in restaurants, or people entering a store, doctors office, air travel, etc. Basically, the use of masks can make societal functions safer and allow more businesses to operate safely enough to be reopened.

Outdoor settings I have less concern about, though I still take a mask with me whenever I go on trails and put it on before I pass someone where it's not easy to get off the trail. (Even then I'm not much worried because for such a short contact time the risk of transmission is very low, but I and most other people in my area see it as respectful to mask up, the idea being to help protect others.)

Even then I'm not much worried because for such a short contact time the risk of transmission is very low, but I and most other people in my area see it as respectful to mask up, the idea being to help protect others.

So it's a symbolic gesture.  If people take it on and off like that, I can imagine the risk of infecting oneself by frequently fiddling with a mask (and thereby become a risk) is greater than the reduced risk of passing anything on.  The risk of transmission from just passing a person on a trail is practically zero unless you cough more or less directly at the person.  To me it would be less a sign of respectfulness than a sign of wrong focus.  Focus needs to be on the actual risks rather than the simply theoretical risks.  If it's considered rude not to wear a mask when you pass someone on a forest trail, the purpose or proper use of masks has been poorly communicated.  Masks are for crowds and medical use and such - as you say, when the other lines of defense don't work.  The solution used over here in stores, restaurants, hotels, etc has been to mount or suspend a transparent screen between staff and customers.  Customers are encouraged to wash or disinfect hands when entering and leaving (people generally do), and to keep a meter's distance in cashier lines.  If meetings, concerts and the like can't be organised so that participants are spaced by a couple of meters, they are rather cancelled or taken online.

That's interesting Wat, but how do you explain the low infection rate of New York (around 1%) vs other states?

I don't think there's any mystery. Look at how much testing and tracing New York is doing. More testing of course means a lower positivity rate for a given number of true infections, but more importantly it also means they have so much data coming in so rapidly that they can tailor the response to the neighborhood level, so every time a new cluster pops up they can stamp it back down quickly and without having to impose restrictions on entire counties or even the entire state.

This is very similar to how China and other countries with SARS experience handle the virus. Testing, tracing, public health interventions, and public education are the best ways to manage the spread of a virus until vaccines are available. And testing is such an important part of that, because you can't solve a problem as easily if you can't narrow down where the problem actually is or how it is changing over time. The whole exercise has to be data driven.

Aside, I think the federal response has largely failed in this regard. It rather seems that their strategy has shifted to not trying to control the spread. They have favored leaving most decisions to the states, which I agree with, but they still have very important roles to play. At the very least they could do a better job on public education, even by something as simple as saying "yes this virus has proven to be a serious threat and everyone can do their part to reduce spread even just by wearing masks in public areas". But instead masks have become politicized because supposedly we can't tell people what to do even when it's for protecting public health. Nevermind that we have state and federal seat belt laws and drunk driving laws...

Wat also want to get your input on this interesting read from the LA times about the low rates that have been maintained in SF throughout.

The timeliness of public health interventions is important, especially during the early phase of exponential growth where things can get out of control so fast. Every day of delay literally costs exponentially more lives. In the above plot we see that deaths per capita correlates extremely strongly to population density, but much of the scatter above and below the best fit line may be related to how soon measures were implemented. Of course the pandemic is ongoing, so continued effectiveness of measures will determine how things go from here.

Washington State currently lies below the trend line, and I think that's because the governor acted very quickly under the guidance of local health officials and university modelling. We were also one of the first states to enforce a statewide mask mandate in public spaces. New York on the other hand lies above the trend line, and I think it is not controversial to say that they could have shut things down earlier (though hindsight is of course 20/20.) But look, both states are 'blue states'. So did party affiliation matter? The plot of deaths/capita vs. density shows that red and blue states are fairly equally clustered around the same trend line, so at the moment I do not agree that state level partisan politics made much difference. 

I say this as dispassionately as possible, because there has been so much passionate debate about politics with the pandemic, and I prefer to see what the data actually show. I remember suggestions early on to not give federal assistance to hard hit 'blue states', and now I see people suggesting it is a 'red state' problem. (Those sorts of claims were an inspiration for making that plot.) I think both perspectives are wrongly motivated, and symptoms of a much deeper problem in this country.

I prefer to micro-analyze based on human behavior and it seems like in what we call "red states" there is a scarcity of mask wearing and not only that- and you brought up a great point about testing- there is less testing and even a discouragement of testing going on!  I'll bring up Utah as a good example.  In Utah a group of mothers has formed that has made a pledge to not get their children tested!  Why?  Because they dont want schools to close.  So in their pledge statement they have stated "If the children are sick we encourage them to stay home but please do not get them tested."  They believe that less testing means lower positivity rates therefore their schools will stay open!  What do you think of this?  Utah is one of several states experiencing record high infection rates and hospitalizations.
So if we pinpoint this to different variables- like percent of people that wear masks and the rate of testing- do we come up with a different result?  We could even create maps correlating rate of mask wearing and rate of testing vs red and blue states!  

At the very least they could do a better job on public education, even by something as simple as saying "yes this virus has proven to be a serious threat and everyone can do their part to reduce spread even just by wearing masks in public areas". But instead masks have become politicized because supposedly we can't tell people what to do even when it's for protecting public health.

But masks are not the first line of defense, nor the second, and simply saying saying that the least people can do is to wear mask could have the effect that people who do wear a mask think they're doing their part if they do so.  And considering how many people use the masks by repeatedly touching their faces, reuse and not washing, it might be harmful if not stressing where masks are appropriate, like on crowded public transport.  The most effective way to stop the virus is to educate people to stay at home if sick, wash hands (anti-bacterial stuff is less good but better than nothing) and to limit their social close contacts, i.e. situations when they're close to other people for several minutes, besides making free testing and tracing easily available.  So stay at home if sick, work from home if possible, don't go to large parties, crowded pubs, church congregations, crowded concerts, whatever which isn't really necessary.  Yes, it's disappointing if you had planned a big wedding, so either postpone the party or make it relatively small and outdoors.  But buying your groceries in a non-crowded store is fine.  Common sense is fine.  It seems to me that masks have become political and symbolical.  It's like fixing something with duct tape.  Is it showing that you're taking things seriously by doing something, or is it a sign that you don't really care about doing things properly?  I mean, masks help in certain situations, so seeing masks then means that you've failed in avoiding those situations.

Dr Fauci has stated that mask wearing should be mandatory in public.  There have been projections that if 95% wore masks the death rate could have been tens of thousands less.  Dr Fauci said that if people wont do it on their own, there should be a mandate for mask wearing because otherwise the pandemic will rage out of control and people should be fined large amounts of money if they take their masks off in public.

Do we have data so we can compare infection or death rates in areas where masks are recommended/mandated for situations where distances aren't an issue vs other areas?  It would be interesting to see if there are any correlation at all.  I favour pragmatic measures over hysterical ones.

Now that Google and Apple have an API in place to detect contacts anonymously, apps could not only warn you if you should go into quarantine, but could also give you a warning when you've "used up" your social contact quota this week even if none of the contacts have been tested positive.

Do we have data so we can compare infection or death rates in areas where masks are recommended/mandated for situations where distances aren't an issue vs other areas?  It would be interesting to see if there are any correlation at all.  I favour pragmatic measures over hysterical ones.

Now that Google and Apple have an API in place to detect contacts anonymously, apps could not only warn you if you should go into quarantine, but could also give you a warning when you've "used up" your social contact quota this week even if none of the contacts have been tested positive.

Yes completely agree- I am looking for data on infections, hospitalizations and death rates in areas where masks are being used more (as well as where more testing is being done.)  I also want to compare it to other factors like BMI, obesity, diabetes, asthma rates, NO2 pollution, etc.  We can make lots of comparisons.

So it's a symbolic gesture.

Yes, in brief close contacts outdoors, it is almost completely a symbolic gesture that tells people that you take the pandemic seriously. I think it's a good symbol, especially in a time of pandemic fatigue, but otherwise I myself understand that the risk of transmission in such situations is very low. Some communicators have done their best to educate about risk factors and the concept of viral load, which has occasionally been picked up by the news and I've previously shared it here as well, but it has not very well reached the general public. Indoors and in crowded spaces, however, wearing a mask is a genuinely good idea and in Washington State has become a state law.
 
Does wearing a mask reduce the risk of transmission? I think a variety of evidence from controlled experiments to studies of actual outbreaks supports that it does. Viral particles are carried along respiratory droplets which have a distribution of sizes. N95 masks utilize some clever physics to block essentially all of the largest and smallest particles, while blocking (in theory) at least 95% of the medium-sized droplets (in practice it may be closer to 90%). But N95's are in short supply and reserved for medical workers, and the public is encouraged to use cloth coverings (though people can still obtain the Chinese variant, KN-95, which I understand has nearly the same specifications.)

Do cloth coverings work? Not as thoroughly as an N95, because they preferentially block the larger droplets, but this is still important. First, if an asymptomatic person is wearing one, it prevents many of the droplets that would travel up to a few meters from entering the air, so it increases the duration of exposure needed to obtain the same viral load. Secondly, if transmission does happen, the reduced viral load may lead to a milder illness.

Do I worry that taking a mask on and off may increase transmission risk due to touching the mask and face? Actually I think it is the opposite. Wearing a mask reduces how often you touch your face, which is especially important in environments where you may be touching contaminated surfaces. Combine with sanitizing the hands before putting on and taking off, and several transmission pathways have been blocked. Outdoors, like when I pass people on trails, I'm not worried at all of the mask becoming contaminated. I'm not touching anything that other people may have touched or sneezed on in that environment. And if I happen to be the one who is infected and pre/asymptomatic, then my mask is not helping to prevent me from getting sick, it's helping to prevent others from getting sick. 

I suspect mask wearing works better in densely populated areas (even outdoors).  Wat have you seen the videos that show that wearing a covering lowers the distance that viral particles travel (from something like 8 ft to 6 inches?)  Also what do you think of these new projections that predict over a half million deaths in the US by the end of February?

Wat have you seen the videos that show that wearing a covering lowers the distance that viral particles travel (from something like 8 ft to 6 inches?)

Oh sure, I've seen a number of demonstrations, ranging from sophisticated with fluorescent particles with realistic size distributions, to just really simple demos using high speed cameras with back-lighting. Gavin of the SlowMoGuys with his interview with Fauci was pretty nice, and actually surprising for showing how many particles are shed by the simple act of talking. It's an important demonstration of how much masks can help if you're having a face-to-face conversation (though I have always shunned people being right up in my face while talking, and now it is normalized behavior to have my conversations about 3 meters apart.)
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