ABSTRACT
This chapter examines the various categories of disease associated with water contact and attempts to define the relationship between pathogens, the water environment, and the water-associated health risks of these pathogens. The infrequent occurrence of typhoid and salmonellosis among bathers in the last 20 to 30 years is similar to the observed decrease in the overall incidence of these diseases. Shigella gastroenteritis has seldom been associated with swimming in polluted water, in spite of the fact that only 10 to 100 bacilli are required for an infectious dose. The association between viral illnesses and water contact in recreational waters has been tenuous because of the difficulty of isolating the etiologic agent from aquatic environments and because many viruses are unculturable. Water contact infections due to mycobacteria other than Mycobacterium tuberculosis usually are associated with sea or brackish waters, although fresh water infections do occur.
