The recent recommendation by the President of the United States that a vaccine containing swine-influenza virus be promptly prepared for mass immunization in the early fall of 1976 was stimulated by the experience at Fort Dix, New Jersey, where, within the last two months, this agent was identified as the cause of disease that led to one death. Transmission from person to person was documented. This fact alone would not have provoked a strong reaction were it not for the suspicion that this was the agent that had probably been responsible for the pandemic of 1918. The basis for this . . .