Sharon and Scott return to TWiV for a Zika virus update, including their work on viral evolution and spread, and whether pre-existing immunity to dengue virus enhances pathogenesis.

Vincent, Dick, and Alan review a new macaque model for HIV-1 infection, a possible role for Epstein-Barr virus in multiple sclerosis, accidental release of H5N1 by a vaccine company, resistance of frogs to virus infection, and extreme virology – the biggest and smallest viruses and viral genomes.