@fifilamoura I'd be much more interested in theories like this if we had sewage outflow monitoring of say skyscrapers or sports stadiums and especially hospitals, but we don't. We're generally monitoring mixed use sewage systems and so this could be as simple as migratory bird shit getting washed into drains or people looking at the headlines and all deciding to dump the raw milk in their fridge down the sink.
@fifilamoura Wastewater monitoring simply isn't useful in this context because you can't separate all the potential causes of the signal and we're dealing with a pathogen which infects not just livestock, but birds, cats, dogs, rodents and a variety of other small mammals all which input into the wastewater system. There may be no cows in the area, but there are plenty of other non-human carriers that could be responsible for the spike.
@fifilamoura I see that as a deficiency in these systems which could be rectified to provide better monitoring and confirmation of when a virus has in fact entered human circulation, by monitoring outflows with exclusively human sources. We also have ILI monitoring at hospitals which feeds into the genetic surveillance system, but that's only going to catch it once it has reached a point where people are being hospitalized...
@fifilamoura ...and at this time of year, there's such a spike in ordinary flu that I'm not sure we're at 100% sampling, so the chances of it getting sequenced may go down.
@fifilamoura It was interesting to watch during the peak of Covid when some countries like the Netherlands had set up systems where they were doing genotyping assays or full sequencing on a high percentage of all Covid cases and you could see true strain prevalence in near real time. It also showed that many waves did not totally wipe out old strains and you still had things like Delta percolating at very low levels long after the majority of cases had moved on.
@fifilamoura It was something you could only do with a system built to hear a pin drop. Just an incredible level of sensitivity to see what was actually circulating. The systems that the US has built are far cruder. We don't even have POC H5 testing deployed nationally, so you wonder how big of a H2H signal will need to build up in a community before the systems we have really have the sensitivity to affirmatively acknowledge it.