To investigate the first influenza-like illness outbreak, and to survey the influenza vaccination rate, awareness rate and willingness among parents for vaccination, so as to provide evidences for the prevention and control of influenza outbreaks.

The epidemiological investigation was carried out to collect the information on the outbreak and the status of influenza vaccination. Samples were collected for viral nucleic acid analysis of influenza and HA gene from the positive samples were sequenced. The awareness of influenza and vaccination was investigated through telephone interviews for the parents of the cases.

The outbreak was caused by influenza virus (A/H3N2). The attack rate was 41.03% in the affected class. The vaccination rates of the class and other classes were 10.26% and 19.53% respectively. The vaccination rates in cases and other students were 6.25% and 13.04% respectively. The parents of the cases who could not distinguish common cold from influenza accounted for 40.00%. There were four reasons for case unvaccinated, they thought vaccination is invalid (53.33%), vaccination leads to illness (33.33%), Illness increases resistance (26.67%), and don't believe vaccine (26.67%).

It is necessary to pay more important on knowledge propaganda about the influenza prevention and the effects of vaccination. It is also important to improve the awareness of disease prevention among students and parents. Before flu season, we should organize vaccination in students as soon as possible so as to improve vaccination rate.

Influenza; Outbreak; Influenza vaccine