A comparison of H1N1 XXXX among pediatric inpatients in the pandemic and post pandemic era.

@entity1 @entity683 @entity649
BACKGROUND: The novel @entity683 H1N1 (A[H1N1]pdm09) strain emerged in 2009, contributing to significant morbidity and mortality. It is not known whether illness associated with A(H1N1) pdm09 in the post-pandemic era exhibits a similar disease profile. OBJECTIVE: The objectives of this study were to compare the burden of disease of A(H1N1) pdm09 @entity683 from the 2009 pandemic year to the post-pandemic years (2010-2014), and to explore potential reasons for any differences. STUDY DESIGN: We conducted a retrospective cohort study of inpatients admitted to @entity1 's Hospital Colorado with a positive respiratory specimen for @entity683 from May-December, 2009 and December, 2010-April, 2014. Univariate and multivariate analyses were conducted to compare the demographics and clinical characteristics of @entity1 with H1N1 during the two periods. RESULTS: There were 388 inpatients with @entity683 (H1N1) pdm09 in 2009, and 117 during the post-pandemic years. Ninety-four percent of all H1N1 during the post-pandemic era was observed during the 2013-2014 @entity683 season. @entity1 with A(H1N1) pdm09 during the post-pandemic year were less likely to have an underlying medical condition (P<0.01). @entity1 admitted to the ICU during the post-pandemic year had a lower median age (5 vs 8 years, P=0.01) and a lower proportion of @entity1 were intubated, had mental status changes, and @entity649 compared with the pandemic years, (P<0.01 for all), with decreased mortality (P=0.02). CONCLUSION: @entity1 with @entity683 (H1N1) pdm09 during the post-pandemic years appeared to have less severe disease than @entity1 with A(H1N1) pdm09 during the pandemic year. The reasons for this difference are likely multifactorial.
