Survey of the epidemic characteristics of influenz in Suzhou from 2010 to 2014

Objective In order to investigate the epidemical characteristics of the Influenza-like illness (ILI) in Suzhou from 2010 to 2014, providing the scientific supports for influenza prevention and control of Suzhou. Methods The influenza samples were collected from the department of respiration of Suzhou Municipal Hospital Division and Suzhou city children's hospital, using fluorescent-PCR method to detect influenza virus nucleic acid and classifying influenza virus subtypes. Results 8035 throat swabs of ILI specimens were collected from 2010-2014 in Suzhou, 959 samples were positive (11.94%), the positive rate of difference of adjacent years was statistically significant (χ2=77.78, P<0.0001). The positive rate was highest in the age group of 10-19 and lowest in the age group of 40-49 among all detected age groups. The influenza epidemic season were winter-spring and summer in Suzhou, type B influenza main in spring and winter, and influenza A in prevalent throughout all year, each subtype showing alternating popular. Conclusions From 2011-2014, influenza virus infected people in every age group of Suzhou, the peak popular time are winter-spring and summer of every year, all kinds of influenza subtype epidemic alternately, so it needs to supervise influenza etiology of Suzhou for a long-term to providing theoretical basis for further control the spread of the flu. Key words: Influenza; Etiology; Surveillance