New Castle County

Could Sewage Be Key to Knowing Scale of Coronavirus Infections?

New Castle Co. is partnering with an MIT startup to see if infections can be traced through wastewater

Wilmington's wastewater treatment plant
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As state and local governments continue to grapple with whether or not to end closures put in place due to COVID-19, officials in Delaware are trying a different approach to understanding the scope of the outbreak: testing sewage.

New Castle County is currently working with MIT startup Biobot Analytics to test its sewage, a partnership which has thus far produced startling results.

The study estimated that some 15,200 people were infected with the virus as of April 15, a far larger number than the 3,442 infections reported statewide as of April 24.

A spokeswoman for the state department of health said the department was not commenting on the study.

Despite the high number, New Castle County executive Matt Meyer, who helped commission the study, said it’s too early to jump to conclusions about the findings.

“How confident am I in the findings that there are 15,200 positive cases in New Castle county? I have just about zero confidence,” Meyer said. “How confident am I in saying that there are many more positive cases than the limited number that we’ve tested? I’m pretty confident in saying that that’s the case as well.”

Founded in 2017, Biobot aims to use wastewater as a “data asset” by thinking of it as essentially being “a community urine or stool sample,” said Newsha Ghaeli, one of Biobot’s co-founders.

The company started looking into the presence of COVID-19 in wastewater about two months ago, she said. To perform the tests, Biobot sends kits to wastewater facilities and has them collect samples over a 24-hour period before sending them to Biobot’s labs for analysis.

New Castle County’s is only one of the approximately 150 wastewater plants across 30 states where Biobot is tracking COVID-19, Ghaeli said. Those utilities serve about 10% of the U.S. population, she said.

“The more samples that we are analyzing and the more locations that we work with and the more time points that we analyze, the more refined our estimates are going to become,” Ghaeli said, emphasizing the need for continuous data collection.

In Delaware, New Castle County has committed to three weeks of testing, which is free to the county except for the cost to ship samples to Biobot, Meyer said. However, he said he hopes the county can continue to send samples for a longer period of time.

Meyer said he hopes to use the information gleaned from the study as “a data point” that might allow the county to gauge how well it’s doing to slow the spread of infections and allocate limited resources toward any virus “hotspots” that it might find.

Ghaeli said she hopes Biobot’s work can be used in conjunction with other tests to help fill in gaps and inform public policy decisions.

“I think this information can be very helpful in really making these difficult and yet critical decisions around how do we open up our cities again, how do we start thinking about sending people back to work, sending kids back to school, because we don’t want to be doing this prematurely. But we also want to be aware of the hit that it’s having on our economy, on mental health and a whole bunch of other things,” she said.

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