Hot tubs, sex, sushi, and infectious diseases

Over the past 20 years, striking and interesting changes in patterns of diseases have occurred due to transmissible agents. Among them are the recognition of new diseases, new clinical manifestations of old diseases, new ecologic niches for traditional pathogens, and new modes of disease transmission. Implicated causes for these changing patterns include alterations in lifestyle with respect to sexual behavior, leisure activity, and dietary trends, together with the impact of immigration and the effects of medical progress. A review of these changes demonstrates the dynamic nature of medicine, and the impact that societal change can have on disease patterns.