Unreal Expectations: The CDC and the Legionnaires’ Disease Outbreak

The shocking onset and scale of what would come to be called the Legionnaires’ disease outbreak in Philadelphia in August of 1976 prompted the Pennsylvania Department of Health to invite the Center for Disease Control (CDC) to aid in the investigation. The arrival of the CDC—a rare government organization with a generally favorable public opinion in the mid-1970s—was met with expectations of a rapid solution to the disease mystery. When the organization proved unable to immediately identify the source of the Legion members’ illness, media and public pressure increased, a flurry of conspiracy theories and volunteered explanations ensued, and charges of malfeasance and incompetence were lodged, culminating in a House Subcommittee hearing on the perceived botched investigatory effort. The dramatic announcement that the cause of the sickness had been identified in January of 1977 opened up a new problem for the organization as it was inundated with samples from around the world to test for that new infectious agent.

The Legionnaires’ outbreak came at a time when the public expected science and medicine to quickly determine public health disease threats, and to be able to promptly protect the public. Perhaps no organization embodied these expectations more than the CDC. The CDC’s inability to immediately solve the puzzle of the outbreak generated anger and suspicion about its motives and capabilities because of the inability to meet the public’s unreal expectations.