TWiV explains why this season’s influenza vaccine is not protecting against mild to moderate disease caused by H3N2 virus, and that antibody-dependent entry of SARS-CoV-2 into monocytes is a major contributor to severe COVID-19.

Ron Fouchier explains why increased transmission of SARS-CoV-2-variants has not been demonstrated, and their ability to displace ancestral variants is due to greater fitness, much like influenza virus antigenic variation leads to better fitness and replacement of previously circulating variants.

From the European Congress of Virology in Rotterdam, Vincent and local co-host Ben Berkhout speak with Ron Fouchier, Rosina Girones, and Marie-Paule Kieny about their careers and their work on influenza virus, environmental virology, and developing an Ebola virus vaccine during an epidemic.

On episode 99 of the podcast This Week in Virology, Vincent tours the 50th Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) in Boston, speaking with exhibitors and visitors, including Professors Derek Smith, Michael Schmidt, Frederick Hayden, and Myra McClure.