Unchanged Severity of Influenza A(H1N1)pdm09 Infection in Children during First Postpandemic Season

摘要

We conducted a nationwide hospital-based prospec-tive study in Germany of in. uenza A(H1N1)pdm09 cases among children <15 years of age admitted to pediatric inten-sive care units and related deaths during the 2009–10 pan-demic and the 2010–11 postpandemic in. uenza seasons. We identifi ed 156 eligible patients: 112 in 2009–10 and 44 in 2010–11. Although a shift to younger patients occurred in 2010–11 (median age 3.2 vs. 5.3 years), infants <1 year of age remained the most affected. Underlying immunosup-pression was a risk factor for hospital-acquired infections (p = 0.013), which accounted for 14% of cases. Myocarditis was predictive of death (p = 0.006). Of the 156 case-pa-tients, 17% died; the difference between seasons was not signifi cant (p = 0.473). Our fi ndings stress the challenge of preventing severe postpandemic in. uenza infection in chil-dren and the need to prevent nosocomial transmission of in. uenza virus, especially in immunosuppressed children