>Research and findings of Covid-19 in Italian sewerage suggest that Covid-19 might've been circulating in Italy in 2019 [1].

Nah, it is one paper, and they only did PCR which is extremely sensitive.

It is more likely that they contaminated their samples than they found COVID viruses. It is still more likely they had false positives.

Also they didn't sequence it. There is no data on where it would be in the genetic tree of coronaviruses.

From the paper: >Moreover, it was circulating in different geographic regions simultaneously

Very very likely to be sample contamination or another winter coronavirus triggering a positive PCR. It just doesn't make any sense.