Before I get to that, I must report that my claim that the worst is behind us is not looking as good today. For the U.S. as a whole, as of the afternoon update the 3DDRR was 1.52, essentially unchanged from yesterday. Excluding NY, it was 1.50, slightly higher than yesterday’s 1.47
A commenter points to a piece by Zvi Mowshowitz.
My prior at this point is that the difference between a low and high initial viral load of Covid-19 is large. The theory makes too much sense. But with high uncertainty.
…We should be studying with experiments how Covid-19 spreads, and how likely each method is to work, using controlled experiments. Yes, this involves infecting individuals. Considering how many lives are at stake and the ability to test using young healthy volunteers who are then isolated, I fail to see how anyone who objects on the basis of ‘ethics’ knows what that word means, or why we should listen to them.
. . .it does not seem so hard for most of us to avoid direct out-of-household interaction with highly symptomatic people.
That last point raises many questions.
1. The people most likely to give you a high-load infection are the people you live with. Almost by definition, you cannot avoid them. Are you ready to re-open schools and let your kids come home with infections?
2. If the trick to this whole thing is to avoid people who might give you a high-load infection, then can you do that on a normal rush hour on the NY subway?
3. What the heck do we do about nursing homes, where a lot of people with low defense factors live in the same place?
People at risk won’t be safe until there’s either herd immunity or they are vaccinated. With any luck, the vaccines will be available soon.
We already have a good idea of the genetic code which makes the “Spike” surface proteins which are the main antigens that produce the predominant antibodies in people who are immune after having made it through an infection.
With recombinant vaccine technology, we can start mass producing vaccines full of those antigens right away, and give them to people just as soon as they are proven safe and effective. As a matter of technical feasibility, with enough money and people, this could be established within mere weeks. As things typically go, well, it might be a lot longer. Hopefully not the CDC-FDA-SNAFU version of longer.
But again, once those are out there, everything can get back to normal safely without fear. And in the meanwhile, once quick and cheap antibody tests are widely available, those individuals should be able to go back to normal life, so long as we had some reliable ‘passport’ system of gatekeeping.
It seems to me that the path to normalcy will be a gradual burden-shifting from collective policies for everybody, imposed by the state, to individual precautions by the vulnerable, for which they will be personally responsible. They will have to try to stay more isolated, avoid contact, wash and disinfect often, and wear masks and gloves.
In past epidemics, it wasn’t uncommon for subsequent outbreaks or waves to occur. The issue is, if we relax and things start getting worse, we probably don’t have a good ‘throttle’ with which we can tune the amount of lockdown needed each day or week.
The good news about kids is that this semester is shot, and most won’t be going back to germ-factory schools until the end of summer, which buys us all some time.
As a high risk individual, my personal lockdown and the lockdown of my family won’t end until there is a vaccine. So here’s hoping the usual suspects don’t make that 18 months.
If the day is dismal otherwise, then put ore money on the covid trials.
US-wide 3DDRR is going to be inherently noisy — we are looking at a very large country and this statistic aggregates many, many distinct curves. Whenever possible, we ought to look at 3DDRR for narrow geographical regions separately and then reach some reasonable conclusions. Relying on the US measure is like judging climate change by average global temperature — certainly tracking something, but will incredibly high variance.
At least here in Florida there seems to be some weekly seasonality in the reporting: Sunday down Monday up Tuesday back down. Wait a day to cook the crow
Re: 3DDR, I wonder if the weekend caused extra lumpiness in the data. Yesterday’s report from Mass. Dept. of Public Health (Tuesday) showed a huge increase from ~35 to 96 deaths, but then asterisked that saying it included deaths That happened over the weekend but didn’t get confirmed until Monday.
“Highly symptomatic” is not a good indicator of risk of transmission. That is the fundamental problem with SARS 2.0 compared to SARS 1.0. The latter was able to be brought under control quickly because it didn’t really become transmissible until a few days after symptoms presented. That meant that the temperature and other symptoms monitoring worked to identify, isolate and contact-trace those infected knocking down transmission. Coupled with identifying the animal source in the wet markets and destroying it. MERS could not be controlled by source elimination since it comes from camels and there is no way millions of camels will be destroyed in the Middle East.
SARS 2.0, on the other hand, sheds before significant symptoms, or even any symptoms at all. Control via identification and contract-tracing is already been overrun. SARS 2.0 transmission is very much like influenza. It also is showing external stability, on surfaces, and in the air, similar to influenza, SARS 1.0 and MERS. (It is not like the seasonal flu where there is immunity/resistance in the population and quick vaccine formulation.) It will be interesting to see if SARS 2.0 shares the influenza impact of temp/humidity on transmission.
I did find a Feb 2019 study that found correlation between the start of school and the rise in “medically-assisted acute respiratory infections (ARI) among the 5-17 ages with lesser, possibly indicating secondary infections, incidence among the 0-4 and 18-65. So we now have science and not just “anecdotal” stories that kids in school share ARIs and take them home to infect non-school age family members.
https://www.stat.berkeley.edu/~jsteinhardt/publications/R0_CA_NY.pdf
This study looks at the conversion of suspected into confirmed cases, which is yet another data problem, and also at citymapper mobility numbers.
By his view, California is doing a lot better than New York, which is perhaps in part a cars vs subway / detached homes vs tower living issue.
Either way, if he’s on the right track, things are getting a lot better fast.
Re: nursing homes, there have already been a couple of awful cases in Scotland.
https://www.bbc.co.uk/news/uk-scotland-52192572
https://www.bbc.co.uk/news/uk-scotland-glasgow-west-52165397