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.

Vincent, Alan, and Stephen Morse discuss progressive vaccinia in a smallpox vaccinee, arsenic and influenza in mice, facemasks and flu transmission, and antigenic and genetic analyses of the new H1N1 influenza virus.