On the decision to reclose when an outbreak is intensifying. Let me first say that nobody wants to reclose. It is a drastic, disruptive move, to understate it. But we’re in a historic pandemic and when you need to break chains of transmission in a hurry, it’s an effective tool 1/

Why would a jurisdiction need to reclose? Principally if healthcare systems are at high risk of being overwhelmed. Wuhan, Lombardy, NYC illustrate how devastating that scenario can be, and it must be avoided. 2/

But the decision cannot wait until health systems are already overwhelmed. The time from infection to ICU admission is about 3 weeks, so any changes today will not show up in the data for about that long. That’s a long time when you’re headed in the wrong direction. 3/

There are other policy changes that can be implemented in hopes of turning things around. Scaling up contact tracing, requiring masks, focusing closure on high risk activities, risk messaging are useful, and we’ve learned a lot since Mar about how they can be used effectively 4/

But the right time for those moves is early, not after things have gotten bad. If a jurisdiction is less than ~3 weeks away from crisis, it’s a risk to take modest steps and then wait to see if they help. Bc what if they don’t? The timelines here are in the virus’s favor. 5/

I do not know whether any jurisdictions are at the point of needing to reclose. Trends in case counts, hospitalizations and % of tests that are positive are heading in the wrong direction in several states, which is why I bring this up. But… 6/

…whether healthcare systems are under strain is very hard to evaluate as an outsider, and I’m not a specialist in that. But I do think we need to talk about and plan for what we would do if cases surge and if hospitals were to be stressed, just as we planned for reopening 7/7