Epidemiological characteristics of virus A/H1N1 in Nantong city, from 2009 to 2010

Objective To investigate the epidemiological characteristics of Novel Influenza A/H1N1 in Nantong and to provide scientific evidence for its control and prevention.Methods The data were collected from Information System of Disease Control and Prevention in China. Descriptive epidemiological analysis was performed to explore the H1N1 case report and aggregation of epidemics in Nantong between 2009 and 2010.Results The reported incidence rate in 2009 and 2010 were 8.24 per 100,000 and 1.03 per 100,000, respectively. The incidence in Chongchuan district was higher than that in Gangzha district and development district. Cases were mainly concentrated in the 0-29 years old group, which accounted for 81.56% of the diagnosed cases of H1N1,and 53.76% cases were among students. Two epidemic peaks appeared at September and December in 2009, and no case was reported since May in 2010. There were 14 aggregation of the epidemics that broke out in schools in 2009.Conclusion The youths and the students in 0-29 years old group should be the focus population in H1N1 prevention. The continuous monitoring of susceptibility of population, routine surveillance on variation of virus and high sensitivity and specificity of the influenza surveillance system are of great significance in further prevention and control of H1N1.