Effects of depuration of molluscs experimentally contaminated with Escherichia coli, Vibrio cholerae 01 and Vibrio parahaemolyticus.
OBJECTIVE
The aim of the present study was to investigate the behaviour of two pathogenic vibrios (Vibrio cholerae O1 and Vibrio parahaemolyticus) during depuration and to compare it with that of Escherichia coli, used as an indicator of suitability for consumption.


RESULTS
Samples of Mytilus galloprovincialis were experimentally contaminated with E. coli, V. cholerae O1 and V. parahaemolyticus, depurated in a pilot plant using ozone and analysed at selected intervals. Numbers of E. coli and vibrios were estimated using an MPN method. The presence of vibrios was confirmed by the use of PCR. The target genes used were ctx for V. cholerae O1 and the restriction fragment pR72H for V. parahaemolyticus. There was a substantially smaller reduction in the numbers of both vibrios (approximately 1 log) during the depuration process than of E. coli (approximately 3 log).


CONCLUSIONS
The results confirm the inadequacy of E. coli as an indicator that molluscs have been cleansed of other microbiological agents.


CONCLUSIONS
The study confirms the risk associated with the consumption of mussels and the need to correctly conserve and cook them prior to consumption.
Croci
Luciana
L
Laboratorio Alimenti, Istituto Superiore di Sanità, Viale Regina Elena 299, 00161 Rome, Italy. luciana.croci@iss.it
Suffredini
E
E
Cozzi
L
L
Toti
L
L
D000818:Animals; D015169:Colony Count, Microbial; D004926:Escherichia coli / Q000302:isolation & purification*; D008974:Mollusca / Q000187:drug effects / Q000382:microbiology*; D010126:Ozone / Q000494:pharmacology*; D016133:Polymerase Chain Reaction; D014734:Vibrio cholerae / Q000235:genetics / Q000302:isolation & purification*; D014736:Vibrio parahaemolyticus / Q000235:genetics / Q000302:isolation & purification*; D014871:Water Microbiology
D010126:Ozone