Wastewater Wednesday - 2/12/25

Wastewater data is some of the best data we have to know what's going around - people may not test, but the 💩 doesn't lie! So without further ado...

COVID

As the graph above shows, the '24-'25 winter wave is in decline; however, that decline appears to be slowing. This masks a lot of regional variation, however!

Importantly, a number of sewersheds (Milwaukee, Oconomowoc, Janesville, et al) are continuing to show increases, albeit not all as steep as the increases at the start of the wave. Other sites (notably Madison) appear to have settled into a high plateau.

You can click around on the DHS Wastewater site to find your own local sewershed data, but I do want to draw particular attention to Milwaukee South Shore, where the latest data point appears to be alarmingly high. This may be just an anomaly, but it certainly bears watching.

Influenza

Flu A is absolutely rampant in Wisconsin right now, with levels nearly five times higher than they were at this time last year. It is definitely the worst flu season we've had since 2019-20, and probably the worst since the 2009 swine flu epidemic. The data below comes from the Milwaukee Health Department's new wastewater dashboard, which is a great tool to explore. Unfortunately, there's not a lot of subtyping going on in Wisconsin, so it is unclear if any of this flu A is H5N1 (aka highly pathogenic avian influenza). It's likely most of it is the ordinary sorts of flu A, but with dead birds washing up on the shores of Lake Michigan recently, it would be nice if they would do more subtyping!

Summary

There is a LOT of illness going around right now. In addition to COVID and the flu, there is also plenty of RSV, strep, and even whooping cough circulating. The key thing to know is that ALL of these diseases are preventable, because they're ALL airborne, which means the solution is the same: clean the air, stay home when sick, get vaccinated for anything you're eligible for, and WEAR A RESPIRATOR every time you're sharing air.