PHILADELPHIA — While COVID-19 cases in Philadelphia are rising to the point that the city will reimpose a mask mandate, a different metric heralded the uptick a few weeks earlier in other parts of the country. The clues were in poop.
For months, the city’s public health department has been trying to set up a wastewater surveillance system as an early warning signal for coronavirus outbreaks. As home testing becomes more popular and diagnostic testing less accessible to the uninsured, wastewater numbers are an important supplement to increasingly imperfect testing data.
Philadelphia was early on the scene with a pilot program in May 2020, but the city has gone about a year since that initiative ended without studying its wastewater, even as the technique became more popular. It hopes to restart the program in a few weeks.
