Background: On may 1994, a foodborne outbreak took place in Almazora (Castellón, Spain) after a meal with 116 persons. A sanitary study was made to find out the causes and control the outbreak.
Subjects and methods: Inspection of the setting and a case-control study were carried out. Several foods and faecal specimens of 23 patients were investigated. We also study the effect of alcohol on the occurrence of the outbreak.
Results: A hundred people was interviewed (86%), 58 ill persons. Salmonella enteritidis was isolated from faeces and statistically implicated food (odds ratio = 75, IC 95 = 15.6-361), a sandwich with tuna, boiled eggs and vegetables. Among adults, epidemiological analysis showed a protective effect of alcohol, adjusted for age, sex and consumption of the implicated food (p = 0.007).
Conclusions: In the study of foddborne outbreaks by Salmonella enteritidis simultaneous consumption of alcoholic drinks and foods should be taken into account to explain some exposed non-cases.