TWiV discusses whether or not Omicron should be designated a new serotype of SARS-CoV-2, and the finding that amino acid changes that adapt SARS-CoV-2 to mink or ferret do not increase fitness in the human airway.

Daniel Griffin provides a clinical report on COVID-19, Slovlakia’s plan to test all adults for SARS-CoV-2 infection, viral variants arising in Danish mink and their potential threat to humans, why it is unethical to carry out challenge trials, Nipah virus dynamics in bats and spillovers into humans, and direct cardiac damage by spike-mediated cardiomyocyte fusion.

Daniel Griffin provides a clinical update on COVID-19, then Ralph Baric joins TWiV to discuss SARS-CoV-2 transmission, vaccines, diagnostic tests, and a new animal model from his laboratory that does not use transgenic mice.