The TWiVers reveal influenza virus replication in the ferret mammary gland and spread to a nursing infant, and selection of transmissible influenza viruses in the soft palate.

The complete TWiV team reviews identification of the cell receptor for hepatitis B and D viruses, and the cell enzyme that cleaves the genome-linked protein from picornaviral RNA.

Vincent and Dick continue virology 101 with a discussion of virus entry into cells, then answer reader email on colony collapse disorder and viruses that confer a benefit to their host.