Health and economic evaluation of entervirus 71 vaccine immunization on HFMD in Minhang District of Shanghai from 2016 to 2018

Objective To investigate the prevention and control effect of hand， foot and mouth disease （HFMD） after entervirus （EV） 71 vaccine immunization， evaluate economic benefit of EV71 vaccine immunization，and provide evidence for developing HFMD vaccine immunization strategies．

Methods Descriptive analysis was performed on comparing epidemiological characteristics of HFMD before and after EV71 vaccine immunization. Cost-benefit analysis was conducted， in which disease burden of HFMD， coverage of EV71 vaccine immunization， and costs of EV71 vaccine immunization were collected to evaluate the benefit-cost ratio （BCR）.

Results The average incidence of HFMD was 202.17/10 million from 2017 to 2018， which decreased by 43.8% compared with the average of the previous six years（χ ² = 395.49，P<0.05）； the average proportion of severe case decreased by 88.7%（χ ²=40.84，P<0.05）. The prevalence of EV71 in the outpatients from 2017 to 2018 were 2.56%（18/704）， which decreased by 88.7% compared with the previous six years（χ ²=124.74，P<0.05）. The severe and fatal cases were mainly caused by EV71 （84.5% -100.0%）. The average cost of EV 1 vaccine immunization was RMB 526， which was approximately 30.2% of the average cost of HFMD diagnosis and treatment. Coverage of EV71 vaccine was 40.12% from 2017 to 2018 in Minhang. The total costs of EV71 vaccination in Minghang from 2016 to 2018 was 174.89 million RMB. It was estimated that EV71 vaccination strategies had prevented 2 491 outpatients， 232 ordinary inpatients and 54 severe cases. The BCR was determined to be 0.35∶1.

Conclusion EV71 vaccine may reduce the incidence of HFMD， the incidence of severe cases， and the disease burden. It is highly recommended to reduce the immunization costs to increase the immunization coverage.