Question: I read that two days ago, DC implemented a mandatory mask order that requires everyone ages 3+ who is not vigorously exercising or eating/drinking to wear a mask outside the home. I thought DC had been doing alright — didn’t you do a Q&A on that recently?

Answer: We talked about the status of DC in our Q&A of 7/14 and I did write then that “DC is still looking pretty good.” At that time, cases had only slightly risen and test positivity was still very low. In the days that followed, new cases in DC continued to increase alongside an increase in test positivity. As Figure 1 shows, cases are on the rise (yellow bars) — the highest they’ve been since early June. These rising cases are also occurring in the context of rising test positivity rates (blue line of line chart), which means that the case increase is not due to an increase in tests (green bars). Yes, hospitalizations are flat (orange bars) and deaths are low (red bars), but we know these are lagging indicators. Right now, the increasing cases alongside increasing test positivity rate is cause for raising alarm.

As we continually see with COVID, If not tamped down quickly, things can quickly spin out of control. In my opinion, DC is doing the right thing by raising alarm and asking people to carry out an intervention (mask wearing) we know to be protective. It’s likely that DC will need to do even more — roll back the phased reopening — if cases and test positivity continue to rise.

Figure 1. COVID in Washington, DC (data from covidtracking.com)