AILSA CHANG, HOST:
Meanwhile, a number of governors are saying they will base their decisions on science and data. But what exactly is the data they will be looking at? NPR global health correspondent Nurith Aizenman is here to talk about exactly what that data is.
NURITH AIZENMAN, BYLINE: Hi, Ailsa.
CHANG: All right. So let's say you're a state considering opening back up. What are the metrics you can look at to tell you if it is safe to reopen?
AIZENMAN: So it would be great if there were some handy checklist, right?
CHANG: (Laughter) Yes.
AIZENMAN: But we don't have quite - we don't quite have that yet. Instead, a lot of the work being done by scientists right now is to identify just what are even the questions that a state needs to ask itself. And one of those is before you can consider moving to a phase 2 strategy, do you have to get your new infections down to zero? Or could it be slightly higher than that?
And one of the more prominent teams that's modeling this pandemic - they're out of the University of Washington's Institute for Health Metrics and Evaluation - they tell me they're putting together an answer to what is that threshold, and then they'll be forecasting the date by which each state will probably reach it. They say they'll be releasing that work soon.
CHANG: OK. So once a state has reached that level can it just open up? Or are there other targets it has to hit first?
AIZENMAN: Yeah, it's challenging - right? - because even after a state is successful at quashing the current wave of infections, the vast majority of people will still be vulnerable to this virus.
AIZENMAN: So it's clear that unless you have some really robust system for detecting and isolating any new infections, they're going to flare up in a massive transmission chain all over again. And so the consensus is states will want to make sure that they have massive testing capacity to check not just severe cases but even people with very mild symptoms, also a massive team of contact tracers who can figure out, for each person who tests positive, who was that person recently in contact with?
Also, this system might need to include facilities to house people who need to be put in isolation or in quarantine.
CHANG: Whoa - to house people. That would be a new thing here in the U.S., right? What's the idea behind that?
AIZENMAN: Right. So let's say someone tests positive and has mild symptoms. They're not sick enough to go to the hospital, but you don't want to keep them at home and potentially expose their family. So maybe states set up places where people in that situation could go instead, where their condition could be monitored; same idea for people who've been exposed and who go into quarantine. Again, these facilities would be a way to protect their family.
CHANG: OK, so a state needs to know that it has this kind of setup in place and not just the housing. It also needs the testing and the contact tracing in place, yeah?
AIZENMAN: Yeah. And then, of course, for all of these different parameters, the question is, like, you know, how much capacity does a state need? How much housing, testing, contact tracing? Take contact tracing. We're hearing a range of back-of-the-envelope-type estimates. Researchers at Johns Hopkins University say 100,000 contact tracers will need to be hired nationwide. Tom Frieden of - the former director of the U.S. CDC - he said it might be more like 300,000, and states are nowhere near that capacity right now.
CHANG: And I'm assuming testing still continues to be an obstacle, right?
AIZENMAN: Yeah. I mean, the exact number of tests required is still a work in progress, but it's probably going to be massively more than we're currently doing right now.
CHANG: All right, so clearly, a heavy lift still ahead. That is NPR's Nurith Aizenman.
Thank you, Nurith.
AIZENMAN: You're welcome. Transcript provided by NPR, Copyright NPR.