CHARACTERISTIC ANALYSIS ON THE SEASONAL INFLUENZA OUTBREAKS IN A CERTAIN DISTRICT OF SHENZHEN IN 2009

[Objective] To understand the epidemiologic characteristic of influenza outbreaks in Longgang district of Shenzhen in 2009.[Methods] Information about influenza outbreaks was collected for retrospective analysis.[Results] A total of 51 influenza outbreaks were reported in 2009 with an average attack rate of 1.15%.Outbreaks mainly occurred between May and August,and schools were the major sites for influenza outbreak.Type B prevailed in those monitoring specimen of influenza-like illness in 2009 year round,but type A prevailed in outbreaks after the peak time in June.Correlation analysis also indicated that the epidemic time was correlated with the reported time and the extent of influenza outbreak.[Conclusion] Influenza outbreak is seasonal in Longgang district,and students were the high risk group.More attention should be paid for early warning of school influenza outbreaks and students' vaccination so as to control the influenza spread in epidemic areas.