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 TWiVniks review the past week’s findings on Zika virus and microcephaly, and reveal a chicken protein that provides insight on the restriction of transmission of avian influenza viruses to humans.

The TWiVsters explore mutations in the interferon pathway associated with severe influenza in a child, outbreaks of avian influenza in North American poultry farms, Ebolavirus infection of the eye weeks after recovery, and Ebolavirus stability on surfaces and in fluids.