On the other hand, fish such as zebrafish, Nile tilapia, large yellow croaker, and rainbow trout all are predicted to have very low susceptibility to SARS-CoV-2 [77], and no fish cell lines or HeLa cells transfected with ACE2 orthologs of some fish species have shown any infection possibility by SARS-CoV-2 [80]. The gene discussed is ACE2; the disease is infection.