Michael McLaren
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Michael McLaren has not written any posts yet.
Your Update suggests you've realized this by now, but your confusion seems to be stemming from not understanding the difference between _droplets_ (large particles, fall to ground within seconds) and _aerosols_ (small particles, can float for 10s of minutes). The reason why there is an emphasis on staying 6 feet away and being careful of touching contaminated surfaces, but not an emphasis on ventilation, is because it is thought that SARS-CoV2 is mostly expelled as droplets and not as aerosols. The purported contraction disappears in this light.
Droplets are larger particles that fall to the ground within seconds, but can be expelled up to ~6 ft / 2 meters by coughing and sneezing.... (read more)
This ^...Another way to spot check the "100000 cases" estimate without knowing the Wuhan numbers is to consider that that would imply roughly 1e5 / (2^4) = 6250 cases 3 weeks ago (the typical delay between infection and death; assuming 6 day doubling time), which corresponds to 31-125 deaths by today for a case fatality rate in the interval of [0.005, 0.02]. That would be for Ohio alone. As of March 13, the US CDC is only reporting 36 deaths for the country as a whole (source; though reported as 47 deaths here) and Ohio is currently reporting 0 deaths (source). Not to say that this is a definitive argument against there being 100000 cases in Ohio, but it does suggest that this estimate wasn't based on current understanding of the virus and its spread.
Update: On March 13 Trevor Bedford also tweeted a rough estimate of 10K-40K cases nationally.
Comments on hospital capacity models from other threads in this post:
Other models / estimates:
This preprint from Marc Lipsitch and colleagues is relevant,
Li R, Rivers C, Tan Q, Murray MB, Toner E, Lipsitch M. 2020. The Demand for Inpatient and ICU Beds for COVID-19 in the US: Lessons From Chinese Cities. https://dash.harvard.edu/handle/1/42599304
See their Figure 1 where they plot the hospitalization rate during the Wuhan epidemic against US hospital bed capacity to give an idea of how quickly the US would be overloaded in a "Wuhan-like outbreak". They consider ICU beds (2.8 per 10000 adults), empty ICU beds (31.8% of all ICU beds), and what they call "US inpatient beds in community hospitals" (29.7 per 10000 adults). The sum of ICU and community beds comes out to... (read more)
For those who are interested, the class that Uri Alon teaches that goes with this textbook is on YouTube
Nissen et al 2016 ("Publication bias and the canonization of false facts") give a simple model for how publication bias in academic research can have a similar effect to the "information cascades" described in the OP. False scientific claims are likely to be falsified by an experiment, but will sometimes be found to be true. Positive results supporting a claim may be more likely to be published than negative results against the claim. The authors' model assumes that the credence of the scientific community in the claim is determined by the number of published positive and negative results, and that new studies will be done to repeatedly test the claim until... (read more)
Just a note that there still seems to be disagreement and a lot of uncertainty about aerosol transmission https://www.nature.com/articles/d41586-020-00974-w