ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR DETECTION OF AEROMONAS-HYDROPHILA SEROGROUP O-19

An enzyme-linked immunosorbent assay has been developed for the detect ion of Aeromonas hydrophila serogroup O:19 isolated from epizootics in eels. The enzyme-linked immunosorbent assay specificity was confirmed after testing A. hydrophila O:19 and non-O:19 strains from different origins, as well as other Aeromonas species and other fish pathogens s uch as Vibrio vulnificus biotype 2, V. furnisii, V. damsela, Yersinia ruckerii and Edwardsiella tarda. The detection limits for A. hydrophil a O:19 cells were around 10(4)-10(5) cells/well. Artificially infected eels were analyzed and the immunodetection was confirmed by cultural methods. With this methodology A. hydrophila O:19 was successfully det ected in infected eels and water samples. We described two subgroups w ithin the serogroup O:19 (Guinee and Jansen system), one of them prese nts a 50 kDa outer membrane protein as a strong thermostable antigen w hich is not present in the other group.