Barbara Schimmer, Karin Nygard*, Hanne-Merete Eriksen, Jørgen Lassen, Bjørn-Arne Lindstedt, Lin T Brandal, Georg Kapperud and Preben Aavitsland
* Corresponding author: Karin Nygard karin.nygard@fhi.no
BMC Infectious Diseases 2008, 8:41 doi:10.1186/1471-2334-8-41