Rickettsial infections of fish

Piscirickettsia salmonis is the first of the previously unrecognized rickettsial pathogens of fish to be isolated, characterized, and demonstrated to be the etiologic agent of an epizootic disease. However, since the isolation of P. salmonis in 1989, the scope and impact of these pathogens has become increasingly apparent. This growing awareness of the role of the rickettsiae in fish health has led to documentation of rickettsial diseases in diverse species of fish and in disparate geographic locations and aquatic environments. Considerable work remains in order to establish the source, reservoir, and normal mode(s) of transmission of these agents and to devise appropriate methods of disease prevention and control.