https://www.nbcboston.com/news/coronavirus/boston-area-sewage-covid-interview/2227534/

With the Boston-area bracing for an influx of more coronavirus cases, what travels below the cities' streets could give us the clearest picture of an uptick in cases.

"Everybody has a voice in the sewer," said Mariana Matus, cofounder of Cambridge-based Biobot.

Biobot is testing the wastewater at the Massachusetts Water Resources Authority's Deer Island wastewater treatment plant. The company, the first in the United States to try this approach, has shown it can give an early indication of a rise in cases based just on what's in sewage.

"Every time we are flushing the toilet, we are creating a high quality medical sample," Matus said. "It is very unbiased. It includes people who have not been diagnosed, it includes people who may be asymptomatic or refuse to go to the doctor, it is very inclusive, and therefore it is a very good test of what is happening."