An anticipated surge in U.S. Covid-19 infections has “yet to materialize” despite increases in human mobility as states loosen restrictions, the researchers behind a leading coronavirus model used by the White House said in a Wednesday update, and shared preliminary data on which states’ residents are more likely to wear masks while out in public.


Developed by the University of Washington’s Institute for Health Metrics and Evaluation, the model update notes that an approximately two-week lag time exists between increased human mobility and a potential spike in infections, but one has not yet happened.

The institute has not yet “formally incorporated” mask-wearing into its estimates, with that aspect of the model “in progress,” but says it provides insight into human behavior and its relationship to the pandemic.

A survey the institute conducted with crowdsourcing data collection company Premise found that 80% of respondents in 18 states said they “sometimes or always” wore masks when leaving home.

In contrast, the survey found that in four states (Indiana, Oklahoma, South Carolina, and Wisconsin⁠) that just 60% or fewer respondents similarly wore masks outside the home.

Wearing cloth masks or face coverings can help reduce the spread of respiratory droplets and is recommended by the Centers for Disease Control and Prevention.

The protective items have, however, become a political flashpoint in recent weeks, as President Trump has not been seen wearing one and citizens emphasizing personal liberty reject them.

Crucial quote

“Given that cloth masks or face coverings have been shown to reduce transmission risk, these preliminary findings highlight the role of broader mask use as more states ease stay-at-home orders and other types of social distancing policies,” the institute writes in its update.

Surprising fact

After the model’s projected death toll spiked to over 147,000 by August 4, Wednesday’s update has shifted its prediction slightly downward, to about 143,300 by the same month.

What we don’t know

The total impact of easing social distancing guidelines and other restrictions. The Institute said it could take a few weeks, as more is learned about how relaxing policies amid increased human movement and contact patterns. Another key factor, according to the update, is the time lag between exposure to the virus, to infection, and then “full disease progression.”

Key background

Health experts (including Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Disease) have expressed concerns that Covid-19 infections could spike as states begin to relax social distancing guidelines. A May 4 update to the Institute’s model doubled its predicted death toll to 135,000, a revision it attributed to “changes in mobility and social distancing policies.” The death toll was increased in two additional updates, before Wednesday’s update adjusted the prediction downward.

Further reading

COVID-19: What’s New for May 18, 2020 (IHME)

Coronavirus Model Used By White House Now Projecting 147,000 U.S. Deaths By Early August (Forbes)

Coronavirus Model Used By White House Increases Death Toll For The Second Time In A Week (Forbes)

U.S. Death Toll Projections Double As Researchers Measure Impact Of Eased COVID-19 Lockdowns (Forbes)

Coronavirus Model Used By White House Predicts 10% Increase In Death Toll (Forbes)

Coronavirus Deaths In United States Could Peak On Easter, Model Predicts (Forbes)

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