[The influenza pandemic in a Norwegian municipality autumn 2009]

Abstract

Background: In April 2009 the World Health Organization (WHO) declared that spreading of a new influenza A(H1N1) virus had reached epidemic proportions, and on June 11, 2009 they declared that the world was in fact facing a pandemic. In Norway the influenza pandemic was the cause of much activity from health authorities and all levels of the health services. This report concerns pandemic-related work within clinical and community medicine in a municipality in western Norway.

Material and methods: All contacts between the general practitioners (GPs) and patients with influenza-like disease in Austevoll municipality were recorded for the second half of 2009. The lead public health nurse recorded vaccination activity systematically. Absence from secondary school in the municipality was recorded and the Medical Health Officer recorded all pandemic-related activities.

Results: 141 patients living in the municipality (3.2 % of the population) contacted the GP for influenza-like disease. Most cases occurred during weeks 43-47. A large majority of the encounters with the GP during these weeks were with patients below 20 years of age, whereas the age distribution was much more diverse at other points in time. Absence from secondary school was also highest in weeks 43-47. 54 % of the municipality's inhabitants were vaccinated. At the end of the main wave of the epidemic, vaccination coverage had reached 28 %. The Medical Health Officer had a large workload, especially during the main wave.

Interpretation: The influenza epidemic in 2009 hit Austevoll municipality in weeks 43-47. Mass vaccination was started too late to have a major influence on the epidemic. Systematic mapping of the epidemic on a municipal level is a useful supplement to the national surveillance.