October 6, 2020

From Diagnostics to Screening for COVID-19: The U.S. Testing Calculator

Brown University School of Public Health and HGHI update state testing targets in collaboration with NPR.

How many daily tests are needed to frequently screen for COVID-19 and keep people safe in schools, prisons, nursing homes, among grocery store and restaurant workers? How can we democratize testing? The COVID-19 testing calculator, developed by a joint team of researchers from HGHI and Brown University School of Public Health, helps decision makers refine their testing strategy and estimates the number of tests needed to implement their chosen approach.

In the coming months, the U.S. needs to be performing millions of tests each day to open and keep open the economy, send children back to school safely, and finally suppress the coronavirus. The arrival of millions of new antigen tests – such as the 150 million tests for nursing home testing the Trump administration recently announced – and other new testing modalities will allow cities and states to gradually increase their testing. They can expand beyond testing only people with symptoms, and begin to regularly and strategically test more and more asymptomatic people in critical settings.

“We’ve been holding our breath as a country for the last months — waiting for a new technology, waiting for more capacity for testing.”

Dr. Thomas Tsai, Assistant Professor of Health Policy and Management, Harvard T.H. Chan School of Public Health and HGHI Fellow

This screening approach to testing – for example, testing all school children in Colorado once a week – is supported by the COVID-19 testing calculator, which informs decision makers on the number of tests needed. The tool offers five scenarios: base and ideal options, as well as three intermediate options that focus on schools, health care, or the economy.

The goal of the calculator and the accompanying recommendations is to help illustrate the trade-offs decision makers face as they consider how to distribute increasing testing capacity. In the current environment of market-driven testing distribution, those who have the means (sports teams, elite universities, companies on Wall Street) can afford a screening testing approach. Meanwhile, cities and states  lack support and funding from the federal government and congress, and so they struggle to build the infrastructure to regularly screen in critical contexts.

The testing calculator is currently available for download as an Excel file. For an explanation of the methodology, and more information about the five testing scenarios, and further updates to the calculator, please visit globalepidemics.org.