[Influenza in Poland in 2006].

A total number of 251,815 cases of influenza and influenza-like illness registered in Poland in 2006 (incidence 660.4 per 100,000 population). Regionally the incidence varied from 75.6 per 100,000 in swietokrzyskie voivodeship to 1,690.4 in mazowieckie. The highest reported incidence was observed in age group 0-4 years (1,543.1 per 100,000). Children and adolescents under 15 years of age accounted for 34.3% of all cases (age specific incidence 1,434.8 per 100,000). In this age group the incidence varied regionally from 190.2 in lubuskie voivodeship to 3,582.5 in lódzkie. 284 patients (0.11% of all cases) required hospital admission. There were 14 deaths due to influenza, in 71.4% these were persons over 70 years of age. In the epidemic season 2005/06 infections with influenza virus registered in Poland were mainly caused by type B similarly to other parts of Europe. Thirty five influenza strains were isolated, including 6 strains of subtype A/H1, 2 strains of subtype A/H3 and 27 strains of type B. All of these isolates with the exception of one strain of influenza B were antigenically similar to the vaccine strains recommended for the epidemic season 2005/06.