Does COVID-19 Sleep on the Weekends?

Why do case counts always seem to peak towards the end of the week?


Ben Pugh

May 15, 2020

Does COVID-19 Sleep On The Weekends?

Find Free COVID-19 Testing Sites. Only on RelayCare.

DC, Maryland, and Virgina

Why do new COVID-19 cases seem to drop off after the weekends? Does COVID-19 take a rest after the workweek too?

Edited from our original LinkedInPost:

On Thursday, DC announced an overnight jump to 152 new cases— about a 50% increase. The inner-statistician in us was intrigued-- was something funky in the data?

After reviewing all of the covid-19 testing sites in the area, we formulated our own hypothesis: since testing takes 48-72 hours to report, low case counts on Mondays and Tuesdays must be originating from the weekend.

We then wondered-- are testing sites open on the weekends? Certaintly some are, but maybe this could explain the fluctation. We did a quick scan of our database across all open testing sites and got these results:

In many places, testing capacity on the weekends is often 50 percent less than on Mondays. Here’s the data cuts.

While we can't no for sure, this evidence seems to suggest that the limited amount of testing is causing inner-week fluctations in the reported case counts. There are assumptions of course, we assume uniformly distributed the tests administered per location, we excluded tests administered in ED settings. But overall, the story seems to match intuition.

The screenshot is from our app, RelayCare , download and look at the data yourself. I try not to manipulate things too much since lives are at stake— stay up to date and make your own insights. We are the first DC view that aggregates with our neighbors in VA and MD too.

Find Free COVID-19 Testing Sites. Only on RelayCare.

DC, Maryland, and Virgina



Ben Pugh

Founder & CEO, RelayCare

Ben is a mathematician and self-taught full-stack software engineer.