Vincent, Alan, Rich, and Dickson discuss bacteria that can utilize arsenic in place of phosphorus, the passing of Frank Fenner, polio outbreak in The Congo, solving criminal cases of HIV transmission, and classifying viruses by capsid structure.

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.

This week the TWiV team explains CRISPR/Cas, the immune system of bacteria and archaea, how novel viruses are discovered by deep sequencing of small RNAs, and the relationship between dry weather and outbreaks of West Nile virus infection.