title: 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.
abstract: 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.
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway. BernardoRafael.Guzman.Herrador@fhi.no.
authors.forename: Bernardo R
authors.initials: BR
authors.lastname: Guzman-Herrador
authors.affiliation: Institute of Virology, University Medical Centre, Freiburg, Germany.
authors.forename: Marcus
authors.initials: M
authors.lastname: Panning
authors.affiliation: Department of Virology, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Kathrine
authors.initials: K
authors.lastname: Stene-Johansen
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.
authors.forename: Katrine
authors.initials: K
authors.lastname: Borgen
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.|European Program for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.
authors.forename: Margot
authors.initials: M
authors.lastname: Einöder-Moreno
authors.affiliation: Institute of Virology, University Medical Centre, Freiburg, Germany.
authors.forename: Daniela
authors.initials: D
authors.lastname: Huzly
authors.affiliation: Norwegian Food Safety Authority, Head Office, Ås, Norway.
authors.forename: Laila
authors.initials: L
authors.lastname: Jensvoll
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.|European Program for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden.
authors.forename: Heidi
authors.initials: H
authors.lastname: Lange
authors.affiliation: Public Health Office, Freiburg, Germany.
authors.forename: Sigrid
authors.initials: S
authors.lastname: Maassen
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.|Department of Virology, Norwegian Institute of Public Health, Oslo, Norway.
authors.forename: Solveig
authors.initials: S
authors.lastname: Myking
authors.affiliation: Norwegian University of Life Sciences, Oslo, Norway.
authors.forename: Mette
authors.initials: M
authors.lastname: Myrmel
authors.affiliation: Department of Medicine II, University Medical Centre, Freiburg, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Neumann-Haefelin
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.
authors.forename: Karin
authors.initials: K
authors.lastname: Nygård
authors.affiliation: Institute of Clinical Microbiology and Hygiene, Regensburg University Medical Centre, Regensburg, Germany.
authors.forename: Jürgen J
authors.initials: JJ
authors.lastname: Wenzel
authors.affiliation: Norwegian University of Life Sciences, Oslo, Norway.
authors.forename: Ann Kristin
authors.initials: AK
authors.lastname: Øye
authors.affiliation: Department of Infectious Disease Epidemiology, Norwegian Institute of Public Health, Postboks 4404 Nydalen, NO-0403, Oslo, Norway.
authors.forename: Line
authors.initials: L
authors.lastname: Vold
mesh_terms: D004196:Disease Outbreaks; D005506:Food Contamination / Q000032:analysis; D005638:Fruit / Q000821:virology; D005858:Germany / Q000453:epidemiology; D006506:Hepatitis A / Q000453:epidemiology / Q000821:virology*; D030041:Hepatitis A virus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D058889:Molecular Typing; D009664:Norway / Q000453:epidemiology