Before the covid pandemic, wastewater sludge was thought to hold promise as an early indicator of community health threats, in part because people can excrete genetic evidence of infectious diseases in their feces, often before they develop symptoms of illness. Israel has for decades monitored wastewater for polio. But before covid, such risk monitoring in the U.S. was limited largely to academic pursuits.
With the onset of Covid, a research collaboration that involves scientists at Stanford University, the University of Michigan, and Emory University pioneered efforts to recalibrate the surveillance techniques for detection of the Covid-19 virus, marking the first time that wastewater has been used to track a respiratory disease.
That same research team, the Sewer Coronavirus Alert Network, or SCAN, is now a leader in expanding wastewater monitoring to detect monkeypox, a once-obscure virus endemic to remote regions of Africa that in a matter of months has infected more than 26,000 people globally and more than 7,000 across the U.S.
As with covid, data on monkeypox can be used to compare trends across regions, but there are limits to what this kind of monitoring can accomplish. Wastewater monitoring doesn’t pinpoint who is infected; it reveals only the presence of a virus in a given area. And it takes a specialist to analyze the samples.
The virus is thought to be spreading primarily through intimate skin-to-skin contact and exposure to symptomatic lesions, although researchers are exploring other potential means of transmission. For now, the U.S. outbreak is concentrated largely in gay communities among men who have sex with men.
The discovery of monkeypox in San Francisco’s wastewater system in June, the first such finding in the nation, set off alarms in a city with a thriving LGBTQ+ population.
For its Northern California surveillance, SCAN partners with local health officials and universities to collect samples and then sends them to Verily Life Sciences — a health tech company owned by Google’s parent company, Alphabet — for analysis. In the Atlanta area, SCAN is working with Emory and Fulton County health officials.
Not all public health agencies are moving as fast. A wastewater monitoring plan for the virus is only now being put together in Los Angeles County, which had confirmed more than 300 cases of monkeypox by the end of July.
And though California is collecting monkeypox data from its surveillance partners, it’s not available for all regions, underscoring that wastewater monitoring for viruses is still an emerging methodology. (NS/KHN)
