Some countries have been sequencing covid in wastewater to track strains. I wonder if it would be a good idea to do a bit of surveillance of other respiratory illnesses like influenza that way as well since they get a whole city’s worth of data in one sample. Imagine using this at international airports to monitor whether anything of concern is being brought in by travelers . Do humans shed influenza virus in feces and before they show symptoms like with covid which would let local authorities know what to prepare for? wasterwater gives about two weeks warning before cases rise with covid19.