The association between marine bathing and infectious diseases– a review

Worldwide, infectious diseases represent a leading cause of death and disability. Exposure to the ocean, whether through recreation or occupation, represents a potentially significant, but poorly understood, source of infectious diseases in man. This review describes the potential mechanisms whereby marine bathing could lead to infectious diseases in man. Sources of pathogens in the marine environment are described, including human sewage, animal sources, fellow bathers and indigenous marine organisms. The epidemiological evidence for the association between marine bathing and infectious disease is presented, including a consideration of the differing relationship between faecal indicator bacteria levels and illness at point source compared with non-point source settings. Estimating the burden of infectious disease is reliant on public health surveillance, both formal and informal, which is described from a UK perspective in this review. Potential emerging threats at the marine-human interface are discussed, including infections caused by Shewanella and Vibrio bacteria, and the presence of human pathogens in the marine environment that are resistant to antimicrobials.