TWENTY-SECOND ANNUAL EASTERN FISH HEALTH WORKSHOP ROYAL PAVILLION RESORT, ATLANTIC BEACH, NC MARCH 18 - 20, 1997 Attenuated Edwardsiella ictaluri Vaccine for Protection Against Enteric Septicemia of Catfish (ESC) Philip H. Klesius and Craig Shoemaker USDA, ARS Fish Diseases and Parasites Research Laboratory, P.O. Box 952, Auburn, AL 36830 We produced a rifampin-resistant mutant of Edwardsiella ictaluri that stimulated cellular-immunity and protection against ESC in channel catfish. The vaccine appears to be safe and able to provide protection for 4 months or longer, even at a temperature of 18oC. A single bath immersion exposure of 2 minutes to a low number of the rifampin-mutant was found to stimulate strong acquired immunity. Cross-protective studies revealed that the rifampin-mutant provided protection against most but not all isolates of E. ictaluri used for challenge. Catfish immunized with a combination of two isolates were protected against all the isolates. The rifampin-mutant survived long enough within the catfish to cause strong and long-lasting acquired immunity against ESC. Return to 22nd Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page