A review of the taxonomy and seroepizootiology of Vibrio anguillarum, with special reference to aquaculture in the northwest of Spain

A review of the literature shows that although the number of serotypes of Vibrio anguillarum reported from different countries varies, most of the vibriosis outbreaks throughout the world are caused by only 2 serotypes: 01 and 0 2 (European serotype designation). The remaining serotypes, associated mainly with environmental samples such as water, sediment, phytoand zooplankton, are generally non-pathogenic to fish. This raises the question as to whether the 2 major pathogenic serotypes of V. anguillarum (isolated only from diseased or carrier fish) should be considered opportunistic or obligate fish pathogens. In addition, information useful in epizootiological and vaccination studies is presented about the antigenic heterogeneity detected within serotype 0 2 . In this review, emphasis is placed on the presence in the marine environment of vibrios (presumptively assigned to the V. splendidus and V. pelagius) species that are taxonomically and serologically related with V. anguillarum and some of which have been associated with disease in fish cultured on the Atlantic coast of Spain and Norway. The precise phylogenetic position of these V. anguillarum-like organisms are well as their actual threat to marine aquaculture remains to be clarified.