Abstract and Introduction
Abstract
This retrospective cohort study revealed that the presence of pandemic H1N1 influenza resulted in a 77.7% increase of patient visits in the emergency department for influenza like illnesses and a 67.2% increase of hospital days in our hospital by comparing to a regular influenza season (2008–2009 season). However, median length of hospital stay was no different in either period (pandemic: 3 days versus seasonal: 4 days, P = 0.06). Except for the patients hospitalized for pandemic H1N1 influenza (n = 111) were older (median age: 4.7 years versus 1.6 years, P = 0.04) and tended to have pre-existing asthma (21.6% versus 9.0%, P = 0.07) than those hospitalized for seasonal influenza A infections (n = 44), this study found no significant difference between the two comparison groups with regards of other clinical and epidemiological features.
Introduction
During the pandemic H1N1 influenza A infection outbreak in U.S., children and young adults from 5 to 24 years of age suffered highest attack rates and were noted to have the highest incidence of influenza related complications, including severe pneumonia and death. This was in distinct contrast to the pattern observed in seasonal influenza outbreaks. However, studies that compared clinical characteristics of pediatric patients hospitalized for pandemic H1N1 influenza with those hospitalized for seasonal influenza had reported controversial findings. This study was to provide further evaluation of pandemic H1N1 influenza with regards of its impact on emergency department (ED) and its epidemiological and clinical characteristics in pediatric patients.