Risk Factors for Influenza A Variant Virus-related Hospitalization in Children Under 5 Years Old

Background The burden due to influenza-related hospitalization is heavy in children under 5 years old, a high-risk group of severe influenza, but there is little research on the risk factors for such hospitalizations. Objective To explore the risk factors for influenza A variant virus-related hospitalization in children under 5 years old. Methods A retrospective design was used. Children under five years old (n=1 450) with influenza A virus infection were selected from Emergency Department, Beijing Ditan Hospital Capital Medical University during December 2018 to February 2019. Clinical data were collected, including age, sex, baseline chronic disease, time from onset to first contact, time from onset to initiation of antiviral therapy, main clinical features and prevalence of hospitalization. Multivariate Logistic regression analysis was used to identify the risk factors of hospitalization. Results The median age for the children was 2.5 (1.1, 3.9) years, and males outnumbered females (56.5% vs 43.5%) . Thirty-eight (2.6%) had baseline chronic diseases, and 155 (10.7%) were hospitalized. Stepwise univariate and multivariate Logistic regression analyses showed that: younger than 6 months〔OR=5.808, 95%CI (2.650, 12.730) , P48 h〔OR=4.663, 95%CI (1.712, 12.704) , P48 h〔OR=19.835, 95%CI (9.043, 43.502) , P