More than 6x as deadly. The seasonal flu has an average symptomatic CFR of 0,1% in the US, but that is excluding asymptomatics. While the asymptomatic rate is all over the place, some analysis combining both serology and virology suggests that ~50% of people infected with the flu, on average, are asymptomatic. Which would mean that the IFR is closer to 0,05% and that COVID-19 would be x12 as deadly with an IFR of 0,6%.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4586318/
https://www.centerforhealthsecurity.org/cbn/2005/cbnreport_103105.html
It's not exactly likely that it was spread 2 months before first cases were discovered. If that happened somewhere, that must be an outlier. It seems that NY would have nosedived way before they did if that was the case. Also, while the daily peak actually seem to have happened just before the lockdown in many places, that doesn't mean that 13,9% in NY were infected before the lockdown (they said 13,9% not 15%). As far as I know, the test they used were for IgM antibodies, which develops on average a week after you get infected. They took the tests about 5 days ago, so that would mean that from today, those 13,9% were all people who had been infected up to ~12 days ago. Lockdown happened March 22.
https://www.technologyreview.com/20...y-passports-cornavirus-antibody-test-outside/
Based on the antibody testing,
NY has an IFR/mortality rate of 0,6% with confirmed laboratory COVID-19 deaths. 0,8% with "probable" COVID-19 deaths added.
NYC has an IFR/mortality rate of 0,64% with confirmed laboratory COVID-19 deaths. 0,93% with "probable" COVID-19 deaths added.
Santa Clare and LA are lower at roughly 0,2% as you said, same is most likely true for the countries that haven't been hit very hard for various reasons. But Stockholm has around 0,6% as well and the Netherlands around the same. The UK, Italy and Spain probably have not done antibody testing as far as I know, but they are likely in the 0,6%-0,8% range on average as well. Keep in mind, this is with ICU units quadrippled in many countries, mitigation and/or supression, closing down elective procedures and an influx of care and medical supplies. Not just business as usual. What would you guess the mortality rate ends up at, and why?
IHME has changed their projection a few times though. Initially as high as 100.000-200.000 with mitigation, then 60.000 with supression, now it's sitting at 67.000 with supression. All figures by August 4.
https://covid19.healthdata.org/united-states-of-america
I think they are undershooting deaths a bit because states are opening earlier and there's a big backlash againt the supression methods. Misinformation (on both sides) combined with either legitimately desperate people, or just impatient people. That graph is a little outdated and you can see that they projected that after April 20 that the US should be nearing a 1.500-1.700 deaths a day average. However the rolling average for the last week, since 19 April, has been 2.132 a day. The curve isn't going down but plateauing. NYC adding a few hundred deaths a day by the "probable" category plays into it, but only accounts for some of the difference. By May 1 the model is currently predicting 1.000 deaths a day. That wont happen and I wouldn't be surprised if it's still at 2.000 a day by that point.