目的 :监测分析我市流行性感冒的流行和流感病毒变异情况 ,为流感防治对策提供理论依据。方法 :①疫情监测 ,设立哨点医院 ,在内科、儿科门诊监测流感样病例和肺炎病例 ;②病原学监测 ,用鸡胚双腔对监测标本做病毒分离 ,用微量血凝抑制试验 (HI)进行型别鉴定 ;③血清学监测 ,采集不同年龄组的自然人群血清 ,检测甲 1型、甲 3型和乙型流感病毒抗体水平 ,以血凝抑制抗体滴度≥ 1∶10判为阳性 ,滴度≥ 1∶4 0判为有保护性作标准。结果 :监测期间疫情基本平稳 ,2 0 0 1年冬曾出现一个流感样病例发病高峰 ,同时伴随肺炎发病增高。发病构成≤ 14岁占 90 .71% ,≥ 6 0岁较低。2 0 0 1年 10月～ 2 0 0 2年 3月分离出 2株甲 1型流感病毒 ,型别为A1/沪防 / 7/ 99;2 0 0 2年 10月～ 2 0 0 3年 3月分离出流感病毒 7株 ,型别均为B型 ,其中 6株为B/Yamanashi/ 16 6 / 98,1株为B/Victoria。毒株分离出时间与流感样病例发病高峰相一致 ,标本源于 13岁以下患者。人群抗体监测 ,甲 3型流感抗体水平较高 ,抗体阳性率≥ 87 0 5 % ;甲 1型抗体阳性率偏低≤ 2 7 38% ;乙型抗体阳性率 2 0 0 2年为2 1 13% ,明显低于 2 0 0 1年的 74 85 %。结论 :本地人群对甲 1和乙型流感缺乏免疫力 ,下一流行季节存在甲 1和乙型流感流行的可能 OBJECTIVE: To monitor and analyze the prevalence of influenza in our city and the variation of influenza virus so as to provide a theoretical basis for influenza prevention and control measures. Methods: ① Epidemic surveillance, the establishment of the sentinel hospital, in the internal medicine, pediatric outpatient surveillance of influenza-like cases and pneumonia cases; ② etiological monitoring, with chicken double cavity of the virus isolation of monitoring specimens, with a small amount of hemagglutination inhibition test (HI) Serotypes were identified; ③ serological monitoring, serum from different age groups were collected to detect the antibody level of type A, type A and type B influenza virus, and the antibody titers ≥ 1:10 were judged as positive by hemagglutination inhibition antibody, Titers ≥ 1: 40 were judged as protective. Results: During the monitoring period, the epidemic was basically stable. In the winter of 2001, there was a peak incidence of influenza-like illness, accompanied by an increased incidence of pneumonia. Morbidity ≤ 14 years old accounted for 90.71%, ≥ 60 years old lower. Two strains of influenza A (H1N1) were isolated from October 2001 to March 2002, and the type was A1 / Shanghai / 7/99; from October 2002 to 2003 In March, seven influenza viruses were isolated, all of which were type B, of which 6 were B / Yamanashi / 16 6/98 and 1 were B / Victoria. The time to isolate the strain was consistent with the peak incidence of influenza-like illness, with specimens from patients under 13 years of age. In population antibody surveillance, the antibody level of influenza A 3 was higher, the positive rate of antibody was 87 0 5%, the positive rate of type A antibody was less than 2 7 38%, and the positive rate of type B antibody was 21 13 %, Significantly lower than 74 85% in 2001. CONCLUSION: The local population lacks immunity to the H1N1 and influenza B viruses and is likely to be prevalent in the next popular seasons