HuNoV infectivity was assessed via in vitro HIE assay as previously described.25 (link),45 (link) Importantly, this method uses RT-qPCR to assess viral replication
in HIE cells by comparing the increase of norovirus genomic copies
at 72 h postinfection with the genomic copies at 1 h postinfection
(no amplification). Additional details are provided in the SI.