OBJECTIVE To investigate the clinical characteristics of hospitalized children with type A influenza virus post-epidemic.

METHODS Clinical data of 40 hospitalized children with influenza A virus confirmed by influenza virus nucleic acid testing at the 947th Hospital of Army during the period from Feb. to Jun. 2023 were collected and analyzed.

RESULTS The onset age was from 3 months to 12 years old, with a median age of 4 years old, of which 28 cases (70.00%) were aged 0 to 5 years, with spring being the peak of the onset of the disease. Fever and cough were the main clinical manifestations. Comorbidities included pneumonia in 24 cases (60.00%), including 28 cases (70.00%) in children aged 0-5 years, with a significant difference compared to those aged 6-12 years (12 case, 30.00%)(P < 0.05), acute laryngitis in 2 cases, myocardial injury in 5 cases, febrile convulsion in 3 cases, electrolyte disorders in 2 cases, myositis in 1 case, and severe sepsis in 1 case. There were 30 cases (75.00%) of single influenza virus infection, and 10 cases (25.00%) of mixed infection, including 4 cases of mycoplasma infection and 6 cases of bacterial infection. Thirty-two children were given oseltamivir granules orally, of which 11 cases were given within 48 h of fever and 21 cases were given after 48 h. The fever time and hospitalization time in the group given oseltamivir granules within 48 h were lower than those in the group given medicine after 48 h. All children were cured.

CONCLUSION The majority of hospitalized children with influenza virus type A were children under 5 years old. The symptoms were non-specific, with high fever and cough as the main manifestations, and multiple comorbidities might occur, with pneumonia being the most common. Children infected with influenza A might have a mixture of other pathogenic infections. Early diagnosis and treatment generally had a good prognosis.