Importance of molecular typing in confirmation of the source of a national hepatitis A virus outbreak in Norway and the detection of a related cluster in Germany

• Published in: Archives of virology Vol. 160; no. 11; pp. 2823 - 2826
• Main Authors: Guzman-Herrador, Bernardo R, Panning, Marcus, Stene-Johansen, Kathrine, Borgen, Katrine, Einöder-Moreno, Margot, Huzly, Daniela, Jensvoll, Laila, Lange, Heidi, Maassen, Sigrid, Myking, Solveig, Myrmel, Mette, Neumann-Haefelin, Christoph, Nygård, Karin, Wenzel, Jürgen J, Øye, Ann Kristin, Vold, Line
• Format: Journal Article
• Language: English
• Published: Vienna Springer Vienna 01.11.2015; Springer Nature B.V
• Subjects: Berries; Biomedical and Life Sciences; Biomedicine; Brief Report; cakes; Disease Outbreaks; Epidemics; Epidemiology; Food Contamination - analysis; Fruit - virology; Genomes; Germany - epidemiology; Hepatitis A; Hepatitis A - epidemiology; Hepatitis A - virology; Hepatitis A virus; Hepatitis A virus - classification; Hepatitis A virus - genetics; Hepatitis A virus - isolation & purification; Humans; Hypotheses; Infections; Infectious Diseases; Medical Microbiology; Molecular Typing; Norway - epidemiology; outbreak investigation; Public health; Questionnaires; small fruits; Virology; Norway; Germany; Coffee Shop; Berry Sample; Outbreak Case; Outbreak Strain; Outbreak Investigation
• ISSN: 0304-8608; 1432-8798
• DOI: 10.1007/s00705-015-2531-y

In March 2014, after an increase of notifications of domestically acquired hepatitis A virus infections, an outbreak investigation was launched in Norway. Sequenced-based typing results showed that these cases were associated with a strain that was identical to one causing an ongoing multinational outbreak in Europe linked to frozen mixed berries. Thirty-three confirmed cases with the outbreak strain were notified in Norway from November 2013 to June 2014. Epidemiological evidence and trace-back investigations linked the outbreak to the consumption of a berry mix cake. Identification of the hepatitis A virus outbreak strain in berries from one of the implicated cakes confirmed the cake to be the source. Subsequently, a cluster in Germany linked to the cake was also identified.