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Published on: December 3, 2011
[Detection of a hepatitis A outbreak in Ceuta (Spain) through a microbiological surveillance system]
María Teresa Ortega-Maján1, Mercedes Caffaro-Rovira, Dionisio José Herrera-Guibert
1Programa de Epidemiología Aplicada de Campo (PEAC), Centro Nacional de Epidemiología, Madrid, España. maytortega@yahoo.es
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.
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