Revising Conventional Wisdom About Histoplasmosis in the United States

Studies performed during the 1940s-1960s continue to serve as the foundation of the epidemiology of histoplasmosis given that many knowledge gaps persist regarding its geographic distribution, prevalence, and burden in the United States. We explore 3 long-standing, frequently cited, and somewhat incomplete epidemiologic beliefs about histoplasmosis: (1) histoplasmosis is the most common endemic mycosis in the United States, (2) histoplasmosis is endemic to the Ohio and Mississippi River Valleys, and (3) histoplasmosis is associated with bird or bat droppings. We also summarize recent insights about the clinical spectrum of histoplasmosis and changes in underlying conditions associated with the severe forms. Continuing to identify prevention opportunities will require better epidemiologic data, better diagnostic testing, and greater awareness about this neglected disease among health care providers, public health professionals, and the general public.