Influenza surveillance in Norway Dr. Hans Blystad Norwegian Institute of Public Health November 2005

Influenza surveillance Norway From 1975 to 1998 aggregated data (no of cases) were collected weekly from all doctors Since 1999 a sentinel surveillance system introduced with 201 selected reporting units from all parts of Norway. Reporting weekly from week 40 till week 20 the following year Voluntary reporting system from laboratories on diagnosed influenzavirus

Influenza reporting units i Norway (n=201)

Data collected in the influenza season by 201 reporting units (by age group): no. of cases of influenzalike illness per week no. of total patients treated per week total number of patients on the doctor`s list

Influenza surveillance Norway – weekly reporting in the influenza season

Reported data influenza season week