Per my back-of-envelope, possibly a *bit* lower than that if you look at the share of positive tests in Italy. But, yeah, maybe not a lot lower, meaning there may not be a ton of margin for error in re-opening stuff unless other factors reduce the spread. Same issue in NYC.
Pat Bayer @PatBayerNC
16 Apr 2020
My rough back-of-envelope calcs. suggest that relatively flat decline in deaths in Italy post-peak implies that strict social restrictions put in place there a month ago only reduced R to 0.85-0.9. Is this right? Seems like v. bad sign for keeping R<1 while relaxing restrictions.
28
49
6
235
Other factors that seem relevant here: 1) How much herd immunity is there in the very worst affected areas, e.g. Lombardy and NYC? 2) What is the R among different subgroups, i.e. health care workers, other essential workers, rest-of-population?
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2
150
Replying to @NateSilver538
Evidence from China was that centralized quarantine made a big difference relative to quarantine-at-home:
Xihong Lin @XihongLin
7 Mar 2020
Yes. The quarantine-at-home strategy used between 1/23-2/1 in Wuhan ie, some confirmed cases were isolated at home, helped reduce R from 3.8 to 1.25, but not good enough. An important lesson for us to learn. Centralized quarantine of confirmed cases after 2/1 was effective(R=0.3)

Apr 16, 2020 · 7:56 PM UTC