Detection of a hepatitis A outbreak in Ceuta [Spain] through a microbiological surveillance system

Background: The Public Health Department of Ceuta informed the Spanish National Epidemiology Center of an increase in hepatitis A cases detected by the microbiological surveillance system. We conducted a study to confirm the outbreak and to initiate control measures. Methods: A descriptive study and a case-control study were performed. A standardized telephone questionnaire was used to collect information on demographic characteristics, symptoms, and risk factors. Results: Nineteen cases of hepatitis A were identified. Univariate analysis revealed an association between infection and eating raw vegetables (OR = 9.3; 95%CI: 1.5-57.6) or razor-shell (OR = 55; 95%CI: 4.3-703.4). In the logistic regression model, only razor-shell consumption remained a significant risk factor (OR = 36.1; 95%CI: 2.45-530.4). None of the 3 inspected restaurants had public health authorization or records of food purchase histories. Conclusions: We confirmed a hepatitis A outbreak associated with consumption of contaminated razor-shell in homes and restaurants. The microbiological surveillance system was the main means of detecting this outbreak.