Outbreak caused by the SARS-CoV-2 Omicron variant in Norway, November to December 2021

@article{Brandal2021OutbreakCB,
  title={Outbreak caused by the SARS-CoV-2 Omicron variant in Norway, November to December 2021},
  author={Lin T. Brandal and Emily MacDonald and Lamprini Veneti and Tine Ravlo and Heidi Lange and Umaer Naseer and Siri Laura Feruglio and Karoline Bragstad and Olav Hungnes and Liz E {\O}deskaug and Frode Hagen and Kristian E Hanch-Hansen and Andreas Lind and Sara Viksmoen Watle and Arne M. Taxt and Mia Karoline Johansen and Line Vold and Preben Aavitsland and Karin Nyg{\aa}rd and Elisabeth Henie Madslien},
  journal={Eurosurveillance},
  year={2021},
  volume={26}
}
In late November 2021, an outbreak of Omicron SARS-CoV-2 following a Christmas party with 117 attendees was detected in Oslo, Norway. We observed an attack rate of 74% and most cases developed symptoms. As at 13 December, none have been hospitalised. Most participants were 30–50 years old. Ninety-six percent of them were fully vaccinated. These findings corroborate reports that the Omicron variant may be more transmissible, and that vaccination may be less effective in preventing infection… 
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