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CAN Compare: See COVID’s Spread Across the U.S.


By: Lexie Kaplan CAN Compare is our newest feature to give you a quick way to compare states and counties. Specifically, you can:  Compare states by overall risk level and by each key indicator, e.g. incidence, infection growth rate, test positivity rate, ICU headroom, and tracers hiredCompare counties within a state or nationallyCompare a county to its neighboring countiesCompare just...

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...

Types of COVID Tests


Getting tested for COVID can be confusing.  Dr. Nirav Shah, senior scholar at Stanford University School of Medicine, describes the three different COVID tests available today: PCR, serology or antibody, and antigen tests. At Covid Act Now, we hope that this post will give you a clear understanding of which COVID test to get, when to get tested, and how to evaluate the advantages, costs, and...

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...

Infection Rate: Explained


The Infection Rate, or “R(t),” is the number of people one infected person goes on to infect in a specific area, over a specific time. The areas we look at are county and state. The period of time we look at is while a person is contagious (able to spread COVID). In the picture to the right, R(t) is 3. If the R(t) is 3, one person will most likely infect three other people, and those three people...

ICU Headroom Used: Explained


ICU Headroom Used measures an Intensive Care Unit’s (ICU) ability to handle a surge of patients in the case of an outbreak. Metrics like daily new cases and R(t) inform the potential impact on the ICU headroom. You might see similar metrics called “Hospital Capacity.” At Covid Act Now, we chose to measure Hospital ICU capacity because ICUs treat the sickest patients with equipment, like...

Test Positivity: Explained


Test positivity is the percentage of COVID testing that comes back positive. It is not the total number of positive tests. If a state or county has a high test positivity rate, it is a sign of insufficient testing in that area. To make sure there are no unknown infections that could lead to an outbreak, states and counties need to test a large enough percentage of the population. Test Positivity...

Daily New Cases: Explained


Daily new cases, also known as incidence in epidemiology, is the number of new COVID cases per day per unit of population. We use a more clear term, “daily new cases” that doesn’t require expert knowledge and calculate it per 100,000 people in states and counties. Daily new cases answers the question: “How many new infections are in my area each day?” Because we can’t test our entire population...

Recruiting A Volunteer Writer


About Covid Act Now Covid Act Now was launched on March 20. Since then, the model has reached over 10-million Americans, was cited by many counties and states in their decisions to shut down, and has been referenced by Dr. Birx in a White House press briefing. We provide data directly to 10+ governors and state epidemiologists across the country, to the Department of Defense, and to numerous...

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