Wastewater testing is playing an important detective role around the country as health authorities race to find out whether Covid-19 cases have spread from Auckland.
Public health professor Philip Hill raised concerns about the testing on RNZ yesterday, saying there there were doubts about its sensitivity and its ability to distinguish between viable and non-viable virus.
The testing is done by the Institute of Environmental Science and Research.
ESR chief scientist Brett Cowan spoke to Guyon Espiner.
