Influenza season 2013/14 has started in Europe with influenza A(H1)pdm09 virus being the most prevalent subtype

The 2013/14 influenza season has started in Europe. Four countries have reported medium intensity influenza activity, with children under 15 years being the most affected age group. A growing number of countries see increasing rates of influenza-like illness or acute respiratory infection and increasing proportions of specimens positive for influenza A(H1)pdm09 virus. In previous seasons, this subtype was associated with higher reported numbers of severe and fatal cases. Clinicians should offer influenza vaccination to unvaccinated persons belonging to risk groups.