COVID-19 Risks: What Does the Latest Study Tell Us?

Is eating out off the table? Are all gyms and hotels a no-go?

Chana Davis, PhD
4 min readNov 20, 2020


Cafe Lokal in Vancouver features new dividers and lower occupancy

A new study of COVID-19 dynamics generated a flurry of scary headlines regarding the risks associated with restaurants, gyms, and hotels.

“Covid Superspreader Risk Is Linked to Restaurants, Gyms, Hotels” Bloomberg News

Should you never eat out, go to the gym, or stay in hotel, until we are all vaccinated?

It pays to dig a little more deeply and see how this study applies to your context.

What was the study?

The study, published in Nature in November 2020, was called: Mobility network models of COVID-19 explain inequities and inform reopening. It describes a model of how COVID-19 spreads that incorporates data on where people spent time. The researchers applied this model to inform risk-mitigation strategies as part of reopening efforts, and to explore the potential reasons for social inequities in the impact of COVID-19.

Thus, the most important thing to note is that this was a modeling study, not a contact tracing study. They didn’t really know where COVID-19 spread happened, but guessed based on a variety of assumptions, and examined how well their predictions matched reality.

For each location, their COVID-19 predictions were rooted in three key risk factors: i) local COVID-19 rates; ii) length of time spent at that location; iii) density of people at that location (ie. people per square foot).

The study focused on specific types of locations (which they call Points of Interest) including restaurants, hotels, gyms, restaurants, grocery stores, gas station, and other stores, but excluded other locations, like hospitals (see methods for rationale).

What did they find?

The researchers found that you could better predict COVID-19 cases over time when you take into account where people spend their time — specifically, how much time they spend in higher risk environments. Not surprising, but useful nonetheless.

They reported that a small fraction of venue types were responsible for the vast majority of new cases during the study period…



Chana Davis, PhD

Scientist (PhD Genetics @Stanford) * Mother * Passionate about science-based healthy choices * Lifelong learner * Founder: Fueled by Science