RESUMO
In November 2013, the Norwegian Institute of Public Health was notified of a gastroenteritis outbreak following two meetings held at a conference centre. Identical food and beverages were served during the meetings. We investigated in order to identify the vehicle of infection and implement control measures. Meeting participants completed an online questionnaire on consumption of foods and beverages. We asked symptomatic participants to provide a stool sample. We defined a case as diarrhoea and/or vomiting in a participant who became ill within 3 days after the meeting. We calculated attack rates (AR) and adjusted risk ratios (aRR) with 95% confidence intervals (CI) using binomial regression. We conducted environmental investigations. Overall, 147/168 (88%) participants responded, of which 74 (50%) met the case definition. All five stool samples provided were norovirus positive. No kitchen staff reported being sick. Risk of illness was higher in those who consumed raspberry mousse (aRR 3·4, 95% CI 1·4-8·2) and sliced fresh fruit (aRR 1·9, 95% CI 1·3-2·8). Seventy cases (95%) ate raspberry mousse. Frozen raspberries used for the mousse were imported and not heat-treated before consumption. Non-heat-treated frozen raspberries were the most likely outbreak vehicle. Contamination by a food handler could not be excluded. We recommend heat-treatment of imported frozen berries before consumption.
Assuntos
Infecções por Caliciviridae/epidemiologia , Surtos de Doenças , Microbiologia de Alimentos , Doenças Transmitidas por Alimentos/epidemiologia , Alimentos Congelados/virologia , Gastroenterite/epidemiologia , Rubus/virologia , Adulto , Idoso , Infecções por Caliciviridae/virologia , Estudos de Coortes , Feminino , Doenças Transmitidas por Alimentos/virologia , Gastroenterite/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Norovirus/fisiologia , Noruega/epidemiologia , Estudos Retrospectivos , Adulto JovemRESUMO
On 7 March 2014, an increase in hepatitis A virus (HAV) infections was identified in Norway. As of 12 April, 19 cases of HAV infection with a virus strain identical to an ongoing European outbreak have been identified. Six probable cases are currently under investigation. On 11 April, a frozen berry mix cake imported from another European country was found as the likely source of the outbreak; the importer has withdrawn the product in Norway.
