| Objective To analyze the surveillance data of influenza in Lu'an from 2010 to 2015, and explore the epidemic characteristics of influenza in Lu'an for the past 6 years. Methods A total of 15 435 throat case date in the Lu'an people's hospital were collected.between Jan 2010 and Dec 2015, 3 890 samples underwent detection of the influenza viral nucleic acids and identification of the virus subtypes by means of real-time PCR and fluorescent quantitative PCR. The related data of patients with influenza-like illness (ILI) from sentinel hospitals were chosen for epidemiological analysis via the descriptive epidemiology method. Results Among the 3,890 throat swab samples from ILI patients, 422 samples were influenza nucleic acids positive, with total positive rate of 10.85%. Analysis of the virus subtypes showed that there were type A3 of 229 cases (54.27%), lastly type H1N1 of 53 cases (12.56%), unclassified type A of 29 cases (6.87%) and type B of 109 cases (25.83%). Obvious bimodal changes with the seasons could be found in the positive rate of influenza virus, with one peak between July and September, another peak between December and next March. Percent of positive ILI patients in the age groups of under 5 years and 25~60 years were both 23.70%, and difference between the positive rates of male and female groups was not statistically significant (P>0.05). Conclusions During the year of 2010~2015, type A3 influenza virus is probably the major epidemic strain in Lu'an area, and annual distribution of type B influenza is mainly steady. The epidemic process of influenza here showed fluctuating changes of bimodal curve, with one peak between July and September, another peak between December and next March. The infected cases in the age groups of under 5 years and 25~60 years are in the majority. |
