Virus inactivation: lessons from the past.

The organizers of this meeting have assigned two tasks to me. The first is to describe the state of affairs in 1955 when several lots of Salk poliovaccine, which had been formalin-inactivated according to government regulation and had been released for use in children, were subsequently found to have retained a small amount of live virulent virus. The second task is to describe a series of experiments that we conducted 25 to 35 years ago on the influence of cations on the thermostability of viruses. Perhaps there are some lessons to be learned and some benefits for future research to be gained from this history.