Detection of respiratory viruses in the 2009 winter season in Rome: 2009 influenza A (H1N1) complications in children and concomitant type 1 diabetes onset.

We investigated clinical characteristics and complications, particularly type 1 diabetes onset, in children hospitalized for 2009 pandemic influenza A (H1N1) virus and compared number of consultations, rate of hospitalization and virus identification in children hospitalized for acute respiratory symptoms (ARS) during the winter season 2009-2010 and 2004-2005. Patients were tested for 2009 H1N1 virus and 14 respiratory viruses on pharyngeal brush/nasal aspirates, using a RT-PCR or nested PCR assays. Consultations and hospitalizations were extracted from operative system GIPSE. The total number of consultations increased by 12%, consultation rate for ARS by 13% and number of hospitalizations by 56% from 2004-2005 to 2009-2010. In 2004-2005, Influenza A virus was identified in only 7 percent of hospitalized children, while in 2009-2010 the 2009 H1N1 virus was identified in 21%. Three children attending the hospital for ARS and 2009 H1N1 infection had ketoacidosis as the onset manifestation of type 1 diabetes. By comparing the number of new diabetes diagnoses among the two winter seasons, we found a higher number of new diagnoses in October 2009-January 2010 than in the same period in 2004-2005 (19 vs 10). Six children (13%), all presenting with pre-existing diseases, were admitted to the pediatric intensive care unit. No children died. The outbreak of this novel virus has increased pediatric consultation rates and hospitalizations compared with previous winters without causing deaths. The children at highest risk for severe infection are those with comorbidities. The 2009 H1N1 virus seems in some way involved in the pathogenesis of type 1 diabetes.