Investigation on the Outbreak of Type A H1N1 Influenza in a School

[Objective]To understand the epidemic characteristic and causes of type A H1N1 influenza,to take effective measures,to provide experience for disease prevention and control.[Methods]Investigation was carried out on the outbreak of fever in Junior High School from October 27 to November 8 2009 in Ningqiang county.[Results]82 students with type A H1N1 influenza were confirmed,accounting for 8.26%.1,1 and 17 cases were reported on October 27,29 and 29 in 2009 respectively while 1,2,27,21 and 12 cases were reported on November 2,4,5,6 and 7 respectively.The morbidity was 44.44% in class 1 of grade 1 where the first case was diagnosed.Throat swab samples were tested for 20 students,14 of them were influenza A H1N1 influenza virus nucleic acid positive.[Conclusion]This was the outbreak of type A H1N1 influenza.