CategoryModel Updates

Introducing Northern Mariana Islands to the U.S. COVID Coverage Map

Covid Act Now is adding the Commonwealth of the Northern Mariana Islands as the second United States territory on our COVID warning system. Check out our first U.S. territory launch of Puerto Rico.

The Commonwealth of the Northern Mariana Islands is a territory of the United States located in the Pacific Ocean. It has a population of about 51,433 (as estimated in the  2020 census data), with 90% of the population living on Saipan.

Our hope is that this coverage will give residents of the Northern Mariana Islands the power to make informed decisions on subjects from individual education to public policy, like stay-at-home and mask orders.

Covid Act Now is committed to providing individuals and policy-makers with accurate and useful information on COVID trends for all communities dealing with COVID, including U.S. territories. 

Our goal is to build a shared understanding of COVID and inform data-driven decision-making through clear, actionable, and real-time COVID risk data for every U.S resident.

This is what the Northern Mariana Islands’ COVID risk looks like today:

We continue to improve upon available data and accuracy to provide more information to the residents and visitors of the Northern Mariana Islands.

Covid Act Now is open-source, so everything can be freely shared, used, and built upon. Through our partnerships with Georgetown University Center for Global Health Science and Security, Stanford University Clinical Excellence Research Center, Grand Rounds, and more, we are always improving our data.

The following 5 Key Risk Factors are now available at Covid Act Now: Daily New Cases, Infection Rate, Test Positivity, ICU Headroom Used, and Tracers Hired.

To find the COVID data for the Northern Mariana Islands:

The Northern Mariana Islands are visible in the U.S. Coverage Map. You can also type “Northern Mariana Islands” into the search bar located above the map.

County-level data:

The Northern Mariana Islands are made up of four municipalities. We are actively working to improve upon our coverage of these municipalities to provide data that is as complete as possible.

For a description of assumptions and methodology, please see our references and assumptions document along with our data sources presentation.

To learn more about Covid Act Now, visit our about page. or for more information please reach out on our contact page or by email at

Introduciendo Puerto Rico a nuestro Mapa de Intervenciones para Estados Unidos

Estamos contentos de anunciar el lanzamiento de Puerto Rico en nuestro U.S. Coverage Map! Creemos que este es un importante desarrollo dado que Puerto Rico es un territorio que se ve impactado por las políticas públicas de Estados Unidos — pero que hasta ahora, no tenía visualizaciones de datos de COVID a nivel municipal.

Mientras desarrollamos nuestro primer modelo, lamentablemente no tuvimos acceso a datos suficientes para medir el riesgo de COVID en Puerto Rico, pero hemos estado trabajando duro desde entonces para conseguirlos. !Esta es la bienvenida de Covid Act Now a Puerto Rico!

Con estas noticias, así es como se ve el mapa de Puerto Rico hoy, 18 de agosto de 2020.

Puerto Rico es un territorio libre asociado de los Estados Unidos con una población de cerca de 3.19 millones en 2019. Hay muchas municipalidades, similares a counties, y muchos puertorriqueños hablan español. Por este motivo, estamos usando traducciones en inglés y español cuanto más se pueda en nuestras comunicaciones sobre COVID en Puerto Rico, y esperamos expandir las traducciones en nuestro sitio web.

Covid Act Now es un proyecto open-source, que puede ser compartido, usado y expandido libremente. Hay muchas otras plataformas de datos de COVID, y creemos que nuestro factor diferenciador es nuestro foco en datos locales. Somos uno de los primeros proveedores públicos de datos a nivel municipal de datos de COVID para Estados Unidos y actualmente somos el único proveedor de un mapa de datos para Puerto Rico a nivel municipal.

Los siguientes 5 factores clave de riesgo para Puerto Rico están disponibles en Covid Act Now: Daily New Cases, Infection Rate, Test Positivity, ICU Headroom Used y Tracers Hired.

CAN está comprometido a proveer a Puerto Rico la habilidad de tomar decisiones informadas de políticas públicas, desde órdenes de aislamiento, uso de mascarillas a educación individual sobre riesgo. Nuestra meta es construir un entendimiento común respecto de COVID e informar a tomadores de decisión mediante indicadores actualizados, claros y accionables sobre COVID.

Cómo acceder al modelo para Puerto Rico

Puerto Rico es visible en el U.S. Coverage Map. Puedes escribir “Puerto Rico” en la barra de búsqueda ubicada arriba del mapa, la que mostrará el modelo correspondiente.

Datos a nivel municipal

Aunque Puerto Rico tiene muchas municipalidades, todavía estamos trabajando en mostrar la mayor cantidad de datos de COVID a nivel municipal como sea posible. Mientras recopilamos estos datos, quizás notes que no todas las municipalidades de Puerto Rico están disponibles. CAN siempre ha priorizado presentar datos  accionables para que estados, counties y municipalidades actúen rápido para contener el COVID. Este es el primer paso para hacer seguimiento al riesgo en Puerto Rico, mientras seguimos recopilando datos a nivel municipal para mostrar una vista completa de Puerto Rico región por región.


Datos a nivel municipal más completos para Puerto Rico.

Si quieres saber más sobre cualquier información presentada aquí, puedes contactarnos.

Introducing a Critical COVID Metric: Daily New Cases Per 100K Population

Today, Covid Act Now is adding an important fifth metric to our COVID warning system: “daily new cases per 100K population” (also referred to by epidemiologists as “incidence”). The addition of this metric rounds out our warning system by incorporating a measure of how much COVID there is in each community today. Our previous metrics focused on direction of change and preparedness, but incidence corresponds to a person’s actual chances of being infected and suggests how many people will likely be infected in the near future. Learn more here.

Nine state risk scores have changed.

This is what the risk level map of the United States looked like on July 21 with the original four metrics:

This is what it looked like on July 22, with the case incidence metric added:

350 county risk scores have changed. 1800 new counties now have risk scores.

Adding the incidence metric has changed the scores of 350 counties. It has also allowed us to expand our coverage to more counties. Previously, many counties did not have enough data for us to calculate a risk score. CAN has always prioritized providing actionable data, and, since a lot of COVID decision-making by policy makers and residents will happen at the local—rather than state or federal—level, we believe it is critical to provide a county-level view of COVID. 

We will now grade every county with a green case incidence score (less than one new case per day per 100K people) as green overall. If case incidence is not green, our normal grading system applies, whereby a state’s overall color reflects the highest risk color for any one of its metrics. Counties that have not reported how many cases they have will show up as grey. 

Here is what the Covid Act Now map of counties looked like before: 

Here is what it looks like now: 

What does this change mean for my community?

We understand that taking into account Daily New Cases per 100K Population has increased the risk score for many states and counties. This change may be disheartening, but we believe it is important for our COVID risk score to reflect risk as accurately as possible and adding this metric improves our ability to do so. 

In addition to helping our overall risk scoring be comprehensive, this new metric also has an important intuitive interpretation. As incidence increases, so does the risk that you’ll run into an infected individual on your trip to the grocery store or at a barbeque.

We also made a minor change to our contact tracing metric. Read more here.

Check out our Youtube Channel for our educational videos.

To learn more about Covid Act Now, visit our about page. For more information please reach out on our contact page or by email at

Sign up to our alerts to stay up-to-date on the COVID risk level in your area.

Changes to How We Assess Contact Tracing

Based on discussions with public health experts and policy makers, we are responding to feedback on the way we assess contact tracing. We have removed the critical (red) range for contact tracing and it will no longer be possible to be marked critical (red) due to low numbers of contact tracing staff alone. While low numbers of contact tracing staff should be acknowledged, it doesn’t indicate an active or imminent outbreak. In addition, contact tracing is one our least refined datasets, largely because states themselves are highly variable in their reporting of contact tracing data. 

Furthermore, the best metric to measure the success of a contact tracing program is the percentage of new cases not traced to a known case. However, to our knowledge, the only state releasing this data is Oregon. Therefore, as a proxy, we currently look at the number of contact tracers on staff for each state to estimate the number of contacts that could be traced within 48 hours if the contact tracing program was otherwise working perfectly. The number of contact tracers hired is a very unreliable proxy, because we do not know how effective the contact tracing programs are, even if they have enough staff. The number of contact tracing staff reported can also be incorrect. There are other unknowns, such as whether the number of contact tracing staff reported is merely the number of planned hires, or the number of actual hires. We also do not know if contact tracers have been given sufficient training or whether they are following up in person with people who do not pick up their calls.

For all these reasons, we are updating the way we categorize contact tracing. First, we are removing the critical range. It will no longer be possible to be marked red for low numbers of contact tracing staff alone.

The 0-10% range will now be High Risk.

Our Newest Metric: Contact Tracing

Today, Covid Act Now is excited to announce a fourth metric added to our COVID warning system: contact tracing. We will layout how we calculate whether states have sufficient contact tracing capacity, and why we think it is an important metric to assess reopening.

Why Does Contact Tracing Matter?

When people contract the virus, they do not show symptoms right away. Even as states begin to reopen, people will need to quarantine themselves if they have been silently exposed to someone with COVID.

How will they know? That’s where contact tracing comes in.

Because of this problem, it is critical that enough tracing capacity exists to rapidly trace the contacts of individuals who test positive for COVID. Those contacts can be tested, quarantined (if necessary), and asked about whom else they have come into contact with. Because exposed individuals begin infecting others, it is critical that this process be completed in less than 48 hours. If this routine of testing and tracing is done quickly and completely, it can contain COVID, as we have seen in South Korea and Taiwan, and without the need for costly lockdowns.

The White House Coronavirus Task Force’s Guidelines say that contact tracing is a “core responsibility” of states in order to be prepared to reopen. As of May 21, 27 states (CA, CT, DE, FL, HA, IL, IN, KS, KY, ME, MD, MI, MO, MT, NE, NV, NM, NY, NC, ND, OH, PA, RI, SD, WA, WV, and WI) call for contact tracing in their reopening plans. The American Enterprise Institute’s roadmap to reopening says states must massively scale up contact tracing and isolation/quarantine of traced contacts.

How Should We Measure Contact Tracing?

So how do we calculate contact tracing capacity? Experts recommend tracing contacts of someone who tests positive for COVID within 24 hours, to contain the potential of transmission. Based on conversations with practitioners and public health experts, our metric assumes that tracing all contacts for each new positive COVID case requires an average of five full-time contact tracers. 

Therefore, our contact tracing metric measures the percentage of new cases for which all contacts can be traced within 48 hours relative to available contact tracing staff in the state (assuming 1:5 new-positive-COVID-case:contact-tracing-staff ratio).

We use green if greater than 90% of the contacts can be traced within 48 hours, yellow if between 20% and 90% of the contacts can be traced within 48 hours, orange if between 7% and 20% of the contacts can be traced within 48 hours, and red if fewer than 7% of the contacts can be traced within 48 hours.

Here is an example from Wyoming:

As of June 13, Wyoming has an average of 12 new cases per day. If Wyoming needs 5 contact tracers per case, that would be 60 contact tracers necessary to trace all cases in 48 hours. Since Wyoming has 50 contact tracers, that is enough to trace 82% of cases.

What Should The Goals Be?

How did we choose our targets? Research estimates that the infection rate can be driven below 1.0 if 70-90% of cases are identified and 70-90% of those contacts are traced and isolated within 48 hours or less. Therefore, we chose 90% as the cut-off between green and yellow.

The boundaries between yellow, orange, and red are trickier. When less than 90% of positive cases have their contacts traced within 48 hours, contact tracing will likely be insufficient to contain COVID. We use 90% as the boundary between green and yellow. In the absence of expert consensus, we have set inclusive lower thresholds for yellow and orange. We peg the cut-off between yellow and orange at 20% — the number required for there to be one contact tracer per active case per 48 hours — and the cut-off between orange and red at 7%. Every state currently coded red is either currently experiencing a new outbreak or effectively has no tracing capacity.

A state can become green either by increasing the number of contact tracers, or by decreasing the number of new daily COVID infections. We hope that this new metric will help states factor contact tracing capacity into their reopening decisions.

Check out our Youtube Channel for our educational videos.

To learn more about Covid Act Now, visit our about page. For more information please reach out on our contact page or by email at

Exporting Covid Act Now Data to a Spreadsheet

If you’re more familiar with editing or manipulating a spreadsheet than you are with code, we have good news! You can now export the data from Covid Act Now‘s model to your favorite spreadsheet, such as Google Sheets or Microsoft Excel.

The Covid Act Now API, which we launched yesterday, exports in CSV (comma separated value) format. This format can be easily imported into a spreadsheet.

We offer forward projections on the effects of COVID-19 for 50 U.S. States and more than 2,000 U.S. Counties. The projections are available by intervention type. (For more on “inference projections,” see this blog post.)

No Action TakenSocial DistancingShelter-in-Place“Inference Projections”U.S. StatesDownloadDownloadDownloadDownloadU.S. CountiesDownloadDownloadDownloadDownload

To import into Microsoft Excel, first open Excel and select the File Menu. Then, choose Open (File => Open). Navigate and select the CSV you just downloaded.

To import into Google Sheets, first create a new blank Google Sheet. Then choose File => Open. Choose Upload and drag-and-drop the CSV file you just downloaded.

The data is updated at least every three days, and we include a “last updated” field in the download so you can ensure your data is fresh.

If you are in the government using our data to plan your response to COVID, you can reach out to us at Or if you’d like to provide general feedback, thoughts, or questions, you can email us at

Inference Projections for States

Today, Covid Act Now’s U.S. Interventions Model launched inference projections at the state level. You can see inference projections on state graphs at Covid Act Now under the purple label, “projected based on current trends.”

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