Abstract: Objective To study the etiological characteristics of influenza cases and status of influenza vaccination in children ≤ 5 years old in Fuyang City. Methods The influenza cases of children ≤ 5 years old diagnosed in two hospitals in Fuyang City in 2019 were selected as the research objects. Collected demographic information, clinical symptoms, laboratory data, influenza diagnosis results of the child cases, and used a self-made questionnaire to investigate the influenza vaccination among the main guardians of children. Descriptive epidemiological analysis Methods was used to analyze the results, and univariate and multivariate analysis Methods were used to analyze the influencing factors of influenza vaccination in child cases. Results A total of 1 488 cases of influenza in children ≤ 5 years old in Fuyang City were obtained, 818 cases were boys （54.97%）, and 670 cases were girls （45.03%）. There were 774 cases of influenza A （52.02%） and 714 cases of influenza B （47.98%）. The incidences of high fever （>39 ℃） and febrile seizure in influenza A cases were higher than that of influenza B cases （P<0.05 or P<0.01）, and the incidences of runny nose congestion and throat swelling/pain were lower than that of influenza B cases （All P<0.05）. A total of 297 out of 1 488 influenza cases had received influenza vaccination in the past 6 months, and the vaccination rate was 19.96%. The main guardian of the child had a college degree or above （OR=2.273）, the higher the monthly family income （OR=2.057）, and the awareness of influenza vaccine （OR=3.537） were more likely to have vaccination for children within 6 months, and children with a history of influenza vaccination 6 months ago （OR=1.475） were more likely to receive influenza vaccination within 6 months. Conclusion The etiology of influenza cases in children ≤ 5 years old in Fuyang City is influenza A and influenza B, which are roughly the same. The influenza vaccination rate is relatively low, the main influential factors are the education level of the main guardian, the monthly family income, influenza vaccination awareness, and influenza vaccination history of children 6 months ago.

Key words: Influenza, Influenza vaccine, Influenza virus, Epidemiological characteristic, Children