OBJECTIVETo assess the economic implications of an annual vaccination strategy against influenza among people who were on a social-health program.

METHODSA retrospective cohort study was conducted. 1900 persons who had received the influenza vaccine were served as vaccine group, while 1049 persons who did not receive the vaccine were served as controls. Cluster random sampling method was used. Both of these two groups came from Donfang Company in which there were 12,109 employers in total and all of them joined the social health insurance program. The survey was carried out when the influenza vaccine was given one year ago.

RESULTSThe rates of vaccine group and control group for respiratory system diseases and cardiovascular diseases who were hospitalized, were 0.51%, 2.47% and 1.64%, 5.62% which showed 68.90% and 56.05% decrease, when compared with the control group. The crude inpatient rate among vaccinees and control group after receiving the vaccination for three and four month were 0.62%, 0.80% and 0.28%, 1.00% respectively. The inpatient rate of oldest-age group decreased by 53.59%, compared with control group. The cost-benefit ratio generated by the use of influenza vaccine in reducing the hospitalization rate was 6.48:1 for Social Health Insurants in Xi'an city.

CONCLUSIONThe Strategy to vaccinate the social-health-insured residents on influenza in Xi'an city had gained better economic benefits in reducing the hospitalization rate of respiratory system diseases and cardiovascular diseases for mild and old-aged persons.