The sophistry of the term "Legionnaires' Disease".

In January 1977, the C enter for Dis­ ease Control (CDC) of the federal gov­ ernm ent announced1,2 that its scientists had isolated a bacteria-like organism that a p p e a re d to cause th e o u tb reak o f Legionnaires’ D isease. The published scientific evidence that formed the basis of this announcem ent was limited. In ad­ dition, a preliminary report has recently been transm itted by CDC (Septem ber 1977) to directors of state and territorial public health laboratories. W ithin the past few months, the com­ munications m edia have frequently re­ ported the occurrence of sporadic cases of so-called “ Legionnaires’ Disease” attri­ buted to the organism isolated by CDC. As a result of these reports, physicians and the public have been led into believing that the CDC organism has been shown to be primarily responsible for the outbreak o f the illn ess am ong P ennsy lvan ia Legionnaires and guests during their con­ vention in Philadelphia in July 1976. The conclusion that the cause of Pennsylvania Legionnaires’ Disease has been estab­ lished and that the mystery has finally been solved is unwarranted. It bespeaks of sophistry,—a type of reasoning that is superficially plausible but may be, in fact, delusive. Thus, in their communications, CDC neglected to present the alternative hypothesis that their microbe is a sec­ ondary invader that may proliferate in the lungs o f p a tie n ts w ho suffer from pneumonitis caused by a variety of toxic and infectious agents as well as from de­ bilitating diseases. It is our present view that the respira­ tory outbreak that occurred in Philadel­ phia in July 1976 was caused by a toxic agent and that many of the victims de­ veloped secondary pulmonary infections by microbes that probably"include the one described by CDC. Briefly stated, the b e ­ lief that Pennsylvania Legionnaires’ D is­ ease was caused by a chemical toxin is based upon the following observations: