Is Legionnaires disease common?
A. Legionnaires is not rare. It is perceived as rare only because most cases are never detected, and not all detected cases are reported to public health authorities. Because underdiagnosis and under-reporting make incidence of the disease difficult to estimate, figures have varied widely. The (U.S.) Centers for Disease Control and Prevention (CDC), Atlanta, has estimated that the disease infects 10,000 to 15,000 persons annually in the United States, but others have estimated as many as 100,000 annual U.S. cases. Another reason that Legionnaires is falsely perceived as rare is that when cases are detected, the public rarely hears about them. Most casesat least 65 to 80 percent in the United States and the United Kingdom occur sporadically (one or two at a time). Thus, only a small percentage of cases occur as part of the multicase outbreaks that sometimes make the news. Cases of the disease are seldom publicized even when lawsuits are involved, because most Legionnaires lawsuits are s
