An outbreak of Aeromonas hydrophila infection in turtles (Pseudemis scripta)

An outbreak of Aeromonas hydrophila infection with a high rate of mortality (95%) in turtles (Pseudemis scripta) in Italy is reported. Pure cultures of the pathogen were isolated from liver, lung, kidney, and heart specimens of the turtles. The A. hydrophila isolate was resistant to amoxicillin, ampicillin, cephalothin, and trimethoprim-sulfamethoxazole but was sensitive to a number of other antibiotics tested. The study indicates that pet turtles can act as reservoirs of this pathogen and may play an important role in the etiology of Aeromonas-associated human infection

Ecological relationship between Aeromonas and Vibrio spp. and planktonic copepods in the coastal marine environment in Southern Italy

The colonisation of planktonic copepod integument by bacteria belonging to the family of Vibrionaceae is a well described phenomenon. In this study, besides reporting on the occurrence of Vibrionaceae and other enteropathogens, we further report on the bacterial attachment to the Estuarine copepod Acartia margalefi in a faecal polluted coastal lagoon near Naples, Southern Italy. In addition, we also performed a laboratory experiment to study the ability of 7 bacterial strains (Vibrio cholerae non-O1, V. mimicus, V. parahaemolyticus, V. alginolyticus, Aeromonas hydrophila, Escherichia coli and Pseudomonas sp.) to colonise the copepod integument. For this laboratory study, 4 different species of copepods, namely Temora stylifera, A. clausi, Centropages typicus and Paracalanus parvus sampled from the Gulf of Naples (Southern Italy) were used. Scanning electron microscope (SEM) studies on the copepods sampled from the lagoon indicated that the bacterial attachment on the integument of Acartia margalefi was mainly on the ventro-lateral body region of the host and in the joints of the thoracic segments, as well as on the swimming and feeding appendages. This infestation, made by rod-like bacteria, was absent in winter but reached peak values of 70% frequency in June. The laboratory studies showed that while V. cholerae non-O1 and A. hydrophila attached on live and dead copepods, respectively, the V. parahaemolyticus, V. alginolyticus, V. mimicus, E. coli and Pseudomonas sp. failed to colonise either live or dead copepods. Thus, this study provides further valuable information about the ecological relationship between different microorganisms (pathogens) and copepods in the coastal marine environment in Southern Italy

Comparison of putative virulence factors in Aeromonas hydrophila strains isolated from the marine environment and human diarrheal cases in southern Italy.

Aeromonas hydrophila strains isolated from the same geographical region (southern Italy) but from different sources (sea sediments and human diarrhea cases) were characterized for the production of potential virulence determinants, such as production of cytotoxins, cytotonic toxins, hemolysin, and dermonecrotic factors and their capacity to adhere to human intestinal 407 cells in vitro. The results showed that isolates from both the sources produced all or some of the virulence factors which may be involved in the pathogenesis of Aeromonas-associated infections. Our study indicates that further epidemiological studies are necessary to elucidate the public health significance of infections caused by Aeromonas spp