First report of a norovirus outbreak associated with the variant Sydney 2012 in Portugal

Abstract

Introduction: This study describes the investigation of a gastroenteritis outbreak in a group of students, associated with a dinner reunion in February 2013 in Porto, Portugal. Methodology: An anonymous structured questionnaire was developed and sent to 34 students who attended the dinner reunion. Eighteen students completed the questionnaire and thirteen met the case definition (attack rate of 72%). Stools from two students were screened for norovirus by RT-PCR using primer pairs that target the highly conserved polymerase gene and the capsid gene. Results: Norovirus genotyping confirmed the variant Sydney 2012 as the probable cause of the outbreak. Conclusion: This is the first report of an outbreak associated with the new variant Sydney 2012 in Portugal.