Those of you who have been at Kendal since the beginning of the pandemic will remember that we did some wastewater testing to see if any Covid cases were present on our campuses. I wrote about the process here.

We were pioneers, among the very first in our area to do this, and (based on my conversations at a users’ group meeting on Zoom) quite possibly the smallest sewage treatment plant involved in the process early on. Seth Beaver spearheaded our effort.

The company we used for testing was Biobot (which was the first to offer this type of testing, I believe). At first, all our test results were negative. But then, when a Covid case popped up at Crosslands, we saw it in our test results too. We were able to demonstrate that the system was sensitive enough to detect a single infected individual—something that (at the time) no one was sure it could do.

But the price of testing was high, we could only arrange weekly testing, and the delays (due to overnighting refrigerated samples to a faraway lab and processing backups at the lab) were just too great. If we could have gotten immediate, daily results, we would have learned about cases early, well before we had PCR test results to confirm them. But we couldn’t be sure that would happen, and we dropped the project.

Although we aren’t doing any testing at Kendal now, you can still get weekly updates about Covid levels in Chester County’s wastewater on Biobot’s website, if you want to keep track of trends in our surrounding area. There is generally an uptick in wastewater levels a week or more ahead of the County’s official Covid testing statistics (which you can find here).

Biobot has continued to offer Covid testing and has turned it into a huge and successful business. Most customers are large organizations and municipalities that want an early alert to spikes in their Covid cases.

Now, the testing can go far beyond Covid. Lately, Biobot has been running experiments to see what other useful information might be extracted from wastewater. As it turns out, the prevalence of many diseases can be tracked this way. Biobot calls it “wastewater-based epidemiology”. The company looked at 80 pathogens, and found that 76 of them can be detected in wastewater. These include the common gastrointestinal pathogens, like E. coli, Salmonella, and norovirus; but also respiratory viruses (these include the flu virus as well as Covid), and even polio, monkeypox, and sexually transmitted infections.  

To be clear: the company is not yet offering testing for these pathogens. Its report ends with a plea for expanded work on this type of analysis. What’s needed, Biobot says, is improvements in funding, coordination, and logistics. The science is already proven.

I can imagine someday having a desktop machine that could run daily wastewater samples and tell us what diseases we have on campus. When that day comes, we can look back and say we were at the forefront of this technology.