Experience with Pandemic 2009 H1N1 Influenza in a Large Pediatric Hospital

Objective: In 2009, a new strain of influenza A, H1N1, was detected in two children in the United States. It spread quickly and became pandemic (pH1N1), disproportionately affecting children. The aim of the present study was to describe our experience with pH1N1 in a large pediatric hospital. Methods: We reviewed the clinical records of all of the children diagnosed as having influenza A at Children's Hospital, New Orleans, LA, for the period April 2009 to May 2010. Diagnosis was made by rapid influenza test or direct fluorescent antibody. Specimens form hospitalized children were sent to the Louisiana Office of Public Health for confirmation by reverse-transcription-polymerase chain reaction. Results: During the 14-month study period, 10,470 children were tested and 1463 (14%) tested positive for influenza A. Boys were more commonly infected than girls (53% vs 47%, P < .001). Of the cases, 1308 (89%) were ambulatory and 155 (11%) were hospitalized. Hospitalized children were younger, more frequently white, had non-Medicaid insurance, and had comorbidity. Of the 155 admissions, 14 (9%) were admitted to the intensive care unit. Having a comorbidity increased and being black decreased the chances of being admitted to the intensive care unit. Three children died, all with severe neurologic or respiratory predisposing illness. Eight cases of hospital-onset influenza and 6 of repeat infection were detected. Conclusions: pH1N1 burdened pediatric facilities during the 2009-2010 influenza season. Even though most cases were mild and selflimited, some resulted in severe disease and long-term complications.