The cr.yp.to microblog: 2020.12.10 04:44:03

2020.12.10 04:44:03 (1336879322041180160) from Daniel J. Bernstein, replying to "Peter Todd (@peterktodd)" (1336769239676555265):

Apply enough tools to move R to, say, 0.5; serious lockdowns can do this by themselves, but combining several lower-cost tools is smarter. Case numbers go down. Then: (1) Idiotically declare mission accomplished. Or: (2) Keep applying the same tools until the virus disappears.

2020.12.10 05:06:12 (1336884896313184256) from Daniel J. Bernstein:

Some of the basic tools for reducing R, such as testing and tracing and quarantines, become _even more effective_ as case numbers drop (because resources are allocated better), so keeping R far below 1 becomes easier and easier as the weeks go by, and then the virus is gone.

2020.12.10 05:21:16 (1336888687724883968) from Daniel J. Bernstein:

A properly designed control system looks like this: "Consistently test. Aim for the positives each week to be below half of what they were the previous week. If they aren't, ramp up interventions until we've caught up." It doesn't look like this: "Aim for 3% positives each week."

Context

2020.12.09 21:18:24 (1336767172979417089) from "Peter Todd (@peterktodd)":

> Hmmm, not sure what the word "many" is doing here. To be clear, I used the word "many" because I interpreted your claim that "One country after another has successfully eradicated COVID-19 cases; the U.S. reacts with ignorance and denial." as "many" different countries.

2020.12.09 21:20:20 (1336767658973425667) from "Peter Todd (@peterktodd)", replying to "Peter Todd (@peterktodd)" (1336767172979417089):

> The U.S. has repeatedly demonstrated the ability to reduce cases (and hospital strain and deaths). Even this isn't a claim that I would make. Cases reduced going into summer; other coronaviruses/resiratory viruses are clearly seasonal and there's evidence that COVID-19 is too.

2020.12.09 21:23:33 (1336768467056340998) from "Peter Todd (@peterktodd)", replying to "Peter Todd (@peterktodd)" (1336767658973425667):

Regardless, the key thing how I interpret what you are saying is that eradication - zero cases - is feasible, and something that has been repeatedly _demonstrated_. And I dispute that: very few places have actually gotten to zero cases, even with lockdown.

2020.12.09 21:26:37 (1336769239676555265) from "Peter Todd (@peterktodd)", replying to "Peter Todd (@peterktodd)" (1336768467056340998):

Now, if you'd made the claim that you could substantially reduce the number of cases with lockdown, I'd agree with you. But there's a very big difference between reduce and eliminate.