Epidemiology of diarrhoeal disease: implications for control by vaccines.

Vaccines present perhaps the most attractive solution to the worldwide problem of diarrhoeal disease. Epidemiological evidence has important implications for the development and use of such vaccines, and results of studies on diarrhoeal diseases in developing and developed countries, in particular among children, and travellers' diarrhoea are reviewed. The virulence and pathogenicity of various enteropathogens are discussed, and the extent to which immunity may be acquired. It is concluded that the development of appropriate vaccines may be a complex task.