TWiV returns to the 2012 brouhaha over transmission experiments with avian H5N1 influenza virus, re-examines the claim of SARS-CoV-2 RNA integration into human DNA, and reviews the engineering and testing of a genetically stable version of the attenuated type 2 Sabin poliovirus vaccine.

TWiV revisits Brazil’s rejection of Sputnik vaccine, examines influenza transmission via the air from the nasal epithelium of ferrets, and a history of accidental releases of polioviruses and their relevance for eradication of poliomyelitis.

The Guardians of the TWiV-o-verse discuss the process of codon deoptimization for the production of experimental infectious attenuated viral vaccines, and how a respiratory syncytial virus with 619 base changes was rescued by genomes with very large internal deletions.

At Aarhus University in Denmark, Vincent speaks with Trine Mogensen, Søren Paludan, Ole Søgaard, and Madalina Carter-Timofte about their careers and their work on sensing herpesviral DNA, immunodeficiencies that predispose to severe viral infections, and the path to a cure for HIV/AIDS.

The TWiV team covers outbreaks of eastern equine encephalitis virus in the US and poliovirus in the Philippines, and explain how a chemokine induced by HIV-1 infection helps release more virus particles from cells.

The TWiVsters review isolation of a naturally occurring DNA virus from fruit flies, and the cell-type specific function of a small transmembrane protein encoded in an open reading frame upstream of the enterovirus polyprotein.