Sewage may offer early signs of coronavirus outbreaks.
People infected with the coronavirus may shed extremely high amounts of virus in their stool even before they show symptoms — if they ever do — suggesting that testing wastewater may offer health officials a way to spot budding community outbreaks early, researchers have found.
Scientists at M.I.T. and elsewhere compared coronavirus concentrations in sewage from an urban treatment facility in Massachusetts with Covid-19 cases in the same area and found that changes in coronavirus levels in wastewater preceded rises and falls in positive test results by four to 10 days.
Their study has yet to be peer-reviewed, but the findings, along with those in a study published in the October issue of Nature Biotechnology by Yale researchers, suggest that sewage surveillance could play an important role in helping contain the pandemic.