Green, Yellow, Orange Or Red? This New Tool Shows COVID-19 Risk In Your County

Jul 1, 2020
Originally published on August 12, 2020 10:15 am

Updated Aug. 12 at 1:15 p.m. ET

How severe is the spread of COVID-19 in your community? If you're confused, you're not alone. Though state and local dashboards provide lots of numbers, from case counts to deaths, it's often unclear how to interpret them — and hard to compare them to other places.

"There hasn't been a unified, national approach to communicating risk, says Danielle Allen, a professor and director of the Edmond J. Safra Center for Ethics at Harvard University. "That's made it harder for people," she says.

Allen, along with researchers at the Harvard Global Health Institute, is leading a collaboration of top scientists at institutions around the country who have joined forces to create a unified set of metrics for the coronavirus pandemic, including a shared definition of risk levels — and tools for communities to fight the virus.

The collaboration launched these tools Wednesday, including a new, online risk-assessment map that allows people to check the state or the county where they live and see a COVID-19 risk rating of green, yellow, orange or red. The risk levels are based upon the number of new daily cases per 100,000 people.

A community that has fewer than one daily new case per 100,000 is green. One to 9 is yellow; between 10 and 24 is orange; and 25 and above puts you in the red. "When you get into that orange and red zone it means, in all likelihood, you're seeing a lot of velocity, a kind of fast upward trend," Allen says.

This is by no means the only attempt to categorize risk levels across the United States. There are a number of frameworks out there using different measures. And that can lead to confusion, says Allen. "What we really need is a shared vocabulary and shared way of presenting data across jurisdictions," she says. This effort represents the consensus of eight institutions and more than a dozen individual experts who have agreed on these metrics.


There are other important metrics when it comes to tracking the spread and severity of COVID-19. Local government leaders need to know how many people are dying and how many people are hospitalized. They need to know how many tests are coming back positive in an area. (The lower the positivity rate, the more likely a community is testing enough to accurately detect the spread of the virus.)

But the group settled on tying the alert level to numbers of new COVID-19 cases per 100,000, because that's a good indicator to show the current picture of outbreaks and compare them in a consistent way. It's a standard way to measure the risk against the total population.

"It allows you to compare a rural area in upstate New York compared to New York City and have an apples-to-apples comparison for relative impact and relative caseload," says Ellie Graeden of Talus Analytics and the Center for Global Health, Science and Security at Georgetown University, which is part of the convergence group that developed the metrics.

Also, by sticking with a standard, core metric you can compare trends over time. "You want to know whether things are going up or down," Allen says.

For the public, this means you can now compare the case incidence where you live to that of, say, a nearby county where you're considering going on an errand. Or the county where your parents live if you're considering a visit. It gives you a way to assess your community's risk level compared to others, at a glance, and modify your behavior accordingly.

For policy-makers, the risk levels are meant to signal the intensity of the effort needed to control COVID-19 and to trigger specific interventions. The collaborative released guidance for how state and local leaders should manage their response, depending on their risk level.

"As this [pandemic] unfolded, a lot of us were waiting for the federal government to stand up and really produce ... some practical guidance on how those at the state and local level should be responding," says Graeden. But in the absence of that clear guidance, this collaboration aims to fill the void.

If a jurisdiction is at the green level, it's on track for containing the virus. At yellow, a community should implement measures such as mask-wearing and social distancing and have an active program of testing, contact tracing and isolation — including targeted testing of those in high-risk environments. Orange is considered "dangerous" and requires surging testing and contact tracing efforts — or if that's not possible, it may call for stay-home orders.

At the red level, "jurisdictions have reached a tipping point for uncontrolled spread," according to the collaborative's guidance. At this level, "you really need to be back at a stay-at-home [advisory]" Graeden says.

The idea is to take some of the guesswork out of the policy response at a local level, says Graeden, and offer a more standardized way to communicate the risk and the response options.

"We've all modified our metrics to align more accurately across the different platforms," she says. "We're now communicating and all agreeing on the same basic thresholds for the types of actions that need to be taken. "

The shared metrics and guidance will be incorporated into a number of initiatives and sites focused on COVID-19 response, including, led by a group of disease outbreak experts and former public health officials, and CovidActNow, led by former technology executives and a group of academics. The convergence group hopes to see it adopted more widely and used by local and state governments.

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The U.S. is overwhelmed by COVID-19, and hearing about COVID-19 is getting overwhelming. Listen to Dr. Anthony Fauci talking to members of Congress yesterday.


ANTHONY FAUCI: We are now having 40-plus-thousand new cases a day. I would not be surprised if we go up to 100,000 a day if this does not turn around. And so I am very concerned.

KING: That is a lot. So maybe it's more helpful to have information about your specific community. As of today, there is a new tool that shows the threat level in every single county in this country. It was developed by researchers at Harvard. And NPR's Allison Aubrey knows the details. Hi, Allison.

ALLISON AUBREY, BYLINE: Good morning, Noel.

KING: So up until this point, it hasn't been easy for me, as an individual, to figure out the level of virus spread in my community.

AUBREY: That's right. I mean, state dashboards display a lot of COVID stats. They have number of cases, number of deaths, but it's hard to know how to interpret these numbers. What are the trends? Here's Danielle Allen. She's a professor at Harvard. She's working with the Harvard Global Health Institute.

DANIELLE ALLEN: A big challenge has been the absence of a unified national way of presenting data and talking about how to think about risk.

AUBREY: So Allen, along with a big group of collaborators - top scientists and former public health officials at institutions around the country - they have stepped in. They've developed this new tool that's being released this morning.

KING: How does it work?

AUBREY: Well, you go to the website - We have a link to it on our site - You hover over the state and county where you live, and you'll see two important things, Noel. You'll see a trend line in cases over time, and you'll see a color - either green, yellow, orange or red. This is the risk level for your county. Now, this level is based on how many new cases there are per 100,000 people. And the value of kind of tying the alert level to this metric is that it's a standard way to measure the risk against the, you know, total population. You're getting apples-to-apples comparisons.

Here's Ellie Graeden. She's one of the collaborators on the project. She's affiliated with Georgetown University's Center for Global Health, Science and Security.

ELLIE GRAEDEN: So it allows you to compare a rural area in upstate New York compared to New York City, and that's the real value of this effort. We're now communicating and all agreeing on the same basic thresholds for the types of actions that need to be taken.

KING: So what actions need to be taken depending on what color you see?

AUBREY: Sure. Well, if you're in a green area, this signals that your county or state is on track to contain the virus. I should say, there are not too many places there. Orange and yellow - that's where many parts of the country are. And for policymakers, it's a cue that they may need to adjust restrictions depending on the trend line, if it's going up or down. And there is specific guidance from collaborators on steps to take.

For us, the public, it's also a signal to, you know, maintain vigilance, to keep up social distancing and masking, to be very cautious. Red is a signal that a stay-at-home order or some other advisory like that is needed. That's the conclusion of these scientists.

KING: And there are counties and states, I would presume, that are in the red, yeah?

AUBREY: Yes, there are. I should emphasize it's very fluid, constantly changing. But many counties in Arizona and Florida are in the red. So if it were up to these scientists, there would be a shelter-in-place or a stay-at-home order considered there. Also, 20 counties in Texas are red. If you look at the map, much of the country is in orange and yellow, as I said, a smattering of green. I should point out, one way to think about this tool is to guide your own decision-making. If you wanted to visit relatives and you use this tool, you see the county they live in is at a red alert, you may want to reconsider your plans.

KING: And people can find the tool at, right?

AUBREY: That's right. That's right.

KING: NPR's Allison Aubrey. Thanks, Allison.

AUBREY: Thank you so much, Noel. Transcript provided by NPR, Copyright NPR.