FOODBORNE OUTBREAKS CAUSED BY SALMONELLA IN ITALY, 1991-4

This report summarizes studies on 1699 foodborne outbreaks, in Italy, reported to the Istituto Superiore di Sanita (ISS) (the National Insti tute of Health of Italy, Rome) during the period 1991-4, The most freq uently reported foodborne outbreaks were caused by salmonellae (81%), in particular by Salmonella enteritidis and non-serotyped group D salm onella (34% and 33% of the total salmonella outbreaks, respectively). A vehicle was implicated in 69% of the salmonella outbreaks; eggs were implicated in 77% of the outbreaks for which a vehicle was identified or suspected. Salmonella strains isolated in 54 outbreaks were studie d for phenotypic and genotypic characteristics. The isolates belonged to S. enteritidis (50 outbreaks), S. typhimurium (three outbreaks) and S. hadar (one outbreak). In the S. enteritidis outbreaks, phage type 4 was most frequently isolated (64.8%), followed by phage type 1 (14.8 %). The virulence plasmid of 38 megadaltons was found in many differen t phage types of S. enteritidis.