1. Department of Virology, National Institute of Public Health, Oslo,1
2. Department of Microbiology, Sogn and Fjordane Central Hospital, Førde,2
3. Institute of Microbiology, The National Hospital, Oslo,3
4. Department of Microbiology, Nordland Central Hospital, Bodø,4
5. Department of Microbiology, Rogaland Central Hospital, Stavanger,5
6. Laboratory of Microbiology, Vestfold Central Hospital, Tønsberg,6
7. Department of Microbiology, Ullevål University Hospital, Oslo,7
8. Department of Microbiology, Vest-Agder Central Hospital, Kristiansand,8
9. Department of Microbiology, Akershus Central Hospital, Nordbyhagen,9 and
10. Department of Microbiology and Immunology, Haukeland University Hospital, Bergen,10 Norway