Risk Factors for influenza A(H1N1)pdm09 among students, Beijing, China.

Abstract

To identify risk factors associated with influenza A(H1N1)pdm09 among students in Beijing, China, we conducted a case-control study. Participants (304 case-patients and 608 controls, age range 6-19 years) were interviewed by using a standardized questionnaire. We found that in addition to vaccination, nonpharmaceutical interventions appeared to be protective.