Several attempts have been made to develop appropriate vaccination programmes for fish streptococcosis. Considerable variability in the protection achieved has been observed, depending on the fish and bacterial species, the formulation of the vaccine, the route of administration, the age of the fish, as well as the use of immunostimulants. Ravelo evaluated the effect of the inclusion of different mineral and non-mineral adjuvants in the vaccine formulation against L. garvieae, comparing the results with those of the aqueous bacterin. It is interesting to point out that today vaccination against L. garvieae, mainly with adjuvanted vaccines, is a common and effective practice in the majority of trout farms in Spain, Portugal, and other European countries. A first vaccination programme was implemented in Israel from 1995 to 1997 using autovaccines consisting of whole-cell formalin inactivated S. iniae and administered by intra peritoneal injection.