A survey was undertaken to examine sea water and sediment for the presence of Vibrio and Aeromonas spp. along approximately 900<space>km of coast in Southern Italy during early and late summer. A quantitative analysis was also done to evaluate the water fecal contamination at the stations examined. The results indicate that all the investigated areas were submitted to a wide spatial fluctuation of fecal contamination and that Vibrio and Aeromonas spp. were present in both high and low fecal-contaminated stations. Sixty two percent of the investigated samples were positive for Aeromonas spp., while 42% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at <10 2 cells 100<space>ml - 1 . Thus, these findings support the hypothesis that the bacterial indicators (such as fecal coliforms) do not always satisfactorily reflect the hygienic quality of water. The presence of Vibrionaceae on copepods was also investigated. Copepods were sampled at a station located inside the harbour of the city of Naples and were found contaminated by V. cholerae non-O1, V. alginolyticus, V. fluvialis and A. caviae. Furthermore, the antibiotic resistance patterns of isolated bacteria showed the presence of a number of resistant strains among the isolates. In order to discriminate the isolates on the basis of their biochemical profiles and/or antibiotic resistance patterns, cluster analysis was carried out which showed that no unique assay could fully discern these isolates. However, the best discrimination resulted from complete pattern profile based on both biochemical profiles and antibiotic resistance patterns.Cet article decrit les resultats d'une campagne de monitorage entreprise pour etudier la distribution des bacteries des genres Vibrio et Aeromonas dans les sediments et les eaux des 900<space>km de cote de l'Italie du Sud. Les echantillons ont ete collecte en debut et en fin d'ete. Les concentrations de coliformes fecaux dans les eaux de stations d'echantillonnage ont ete aussi mesures. Les resultats montrent que toutes les aires echantillonnees etaient soumises a une forte variabilite spatiale de la contamination fecale et que Aeromonas et Vibrio spp. etaient presente soit dans les stations lourdement contaminees par les coliformes fecaux que dans celles qui n'etaient pas ou peu contaminees. Soixante deux % des echantillons etaient positifs pour Aeromonas spp. et 42% etaient positifs pour Vibrio spp. Trente huit % des stations qui etaient positives pour Aeromonas et Vibrio spp. montraient une contamination fecale de l'eau inferieure a 10 2 coliformes fecaux 100 ml - 1 . Ces resultats confirment l'hypothese que les bacteries indicatrices classiques ne refletent pas la qualite hygienique de l'eau. On a aussi analyse la presence de Vibrionaceae sur les corps de copepodes echantillonnes dans une station situee dans le Golfe de Naples. Les copepodes etaient contamines par V. cholerae non O1, V. alginolyticus, V. fluvialis et A. caviae. Parmi les Vibrionaceae isolees on a trouve nombre de souches qui montraient une resistance aux antibiotiques. Pour discriminer les souches isolees en fonction des leur profils biochimiques et/ou de leur resistance aux antibiotiques on a soumis les donnees a une cluster analysis, qui a demontre qu'il n'y a pas un test unique capable de pleinement discerner parmi les souches. La meilleure discrimination a ete obtenue en considerant ensemble les profiles biochimiques et la resistance aux antibiotiques.