Rich reviews the history of smallpox and the discovery of variola viral genomes in ancient DNA from human remains throughout Northern Europe, which pushes back the earliest date of smallpox virus infection to ~600–1050 CE, overlapping the Viking Age.

TWiV reviews evidence that COVID-19 mRNA vaccination of both uninfected and previously infected persons elicits cross-variant neutralizing antibodies, and directed evolution of a bacterial protein to form a virus-like capsid that specifically packages its encoding mRNA.