A retrospective study on the clinical features of the hospitalized children with influenza in Suzhou from 2005 to 2009 / 中华传染病杂志

ABSTRACT

Objective To analyze the clinical features of the hospitalized children with laboratory-confirmed influenza in Suzhou. Methods The demographic information, laboratory test results, clinical features, treatments and outcomes of the hospitalized children with laboratoryconfirmed influenza were collected retrospectively. The data were analyzed using chi square test,Cochran-Armitage trend test. Results Four hundred and eighty hospitalized children were diagnosed with laboratory-confirmed influenza during the period of 2005 to 2009. Among these cases, 414 were subtype A and 66 were subtype B. The positive rate was 2.66%. Four hundred and nineteen cases (87.29 %) were ≤ 5 years old. Most of the cases developed during winter (from December to April the next year) and summer (from July to August). The age and sex distribution didn't vary from year to year (x2=9. 7768,x2 = 8. 7573; both P＞0.05). The mean disease course was (16.22± 9.41)days, and the mean hospitalization duration was (7.89 ±2.97) days. The percentages of patients with symptoms of fever, dyspnea and diarrhea or requiring oxygen treatment decreased with age (Z =4. 9430, Z=2. 1021, Z=3. 2073 and Z=2. 3277, respectively; all P＜0.05). The percentages of cases with concomitant pneumonia and upper respiratory infection also decreased with age (Z =-3. 8762 and Z=-3. 5095, respectively; both P＜0.01). Fifteen point five percent (60/387 cases)of the cases were co-infected with pneumococcus and 15. 0% (72/480 cases) were co-infected with respiratory syncytial virus (RSV). The level of C-reactive protein was significantly higher in cases with bacterial co-infection than those with viral co-infection (Z= -3.1290, P ＜ 0. 01 ).Conclusions Hospitalized children with influenza are more common in winter and summer in Shuzhou.Many patients are co-infected with pneumococcus or RSV. The symptoms are more severe in younger children.