It looks like the proposed Covid-19 antibody find for Italy from 2019 is not uncontested among the science community, here is a comment from virologist Marion Koopmans [1], who was trying to validate the study's results:
"Yrs, we tried. Sofar have not been able to confirm. Serology in low prevalence situations is challenging so our criteria are stringent ( triple antigen positive and neutralisation). With that no positives pre march 2020 in our country and sofar not in panel from italy"
"Yrs, we tried. Sofar have not been able to confirm. Serology in low prevalence situations is challenging so our criteria are stringent ( triple antigen positive and neutralisation). With that no positives pre march 2020 in our country and sofar not in panel from italy"
[1] https://twitter.com/MarionKoopmans/status/141665264260494541...