A. In earlier posts, we discussed a testing strategy called group testing. The primary benefit of group testing is that it requires fewer testing resources (currently, the US is conducting upwards of 600,000 tests per day, often with lags in results, delaying timely responses to a positive test).
An alternative group testing approach involves analyzing wastewater. Here are a few of the benefits of a Group Poop Test:
1.) Fewer testing resources are needed (since a large group of people are tested at once).
2.) Wastewater testing is not invasive, as long as everyone is negative. (If the wastewater tests positive, then nasal swabs of each individual are necessary in order to figure out which member is positive.)
3.) You can follow trends in viral load longitudinally in the same population that are more localized than the county level.
4.) And most importantly, it can provide early detection of asymptomatic individuals. This allows you to follow up with contact tracing and take appropriate precautionary steps to reduce spread.
Check out this recent success story at the University of Arizona. One of the dormitories had wastewater test positive for the novel coronavirus, which led to individual nasal swab testing of the 300 or so residents. This testing identified two asymptomatic positive cases, who were then quarantined. This early detection and follow up likely prevented an outbreak across the dorm and campus.
https://www.washingtonpost.com/…/arizona-coronavirus-wast…/…
The CDC is initiating a National Wastewater Surveillance System.
https://www.cdc.gov/…/cases-up…/wastewater-surveillance.html
Here’s a link showing wastewater testing results over time in Massachusetts.
http://www.mwra.com/biobot/biobotdata.htm…
Finally, here’s additional reading about strategies to build COVID-19 monitoring infrastructure.
https://www.mckinsey.com/…/shifting-focus-to-a-comprehensiv…#
