Abstract: Objective To analyze the EV 71 vaccination status in the 2012-2021 birth cohort in Lianyungang City and provide a basis for formulating vaccination strategies and scientific prevention and control of hand-foot-mouth disease. Methods Using the Jiangsu Vaccination Provincial Management Information System, we established the birth cohort of age-eligible children since EV 71 vaccination began in 2017 in Lianyungang City, and analyzed the EV 71 vaccination status of these children. Results A total of 500 016 children managed in the 2012-2021 birth cohort in Lianyungang City. As of December 31, 2021, 71 715 children in the 2012-2021 birth cohort in Lianyungang City had received the first dose of EV 71 vaccine, with a vaccination rate of 14.34%; 60 915 children were whole-course vaccinated, with a whole-course vaccination rate of 12.18%. The vaccination rate and whole-course vaccination rate of EV 71 vaccine were highest in 2018 for children in the 2012-2021 birth cohort, and the highest in the second year of life for children in the 2018-2020 birth cohort. The median age for the first dose of vaccination was 14 months （interquartile range 15 months）.Migrant children, urban children, and girls had higher EV 71 vaccination rate and whole-course vaccination rate （all P<0.01）. Conclusions The EV 71 vaccination rate of children in the 2012-2021 birth cohort in Lianyungang City has increased but is still relatively low. Due to the late age of starting immunization, there are some differences in EV 71 vaccination among children with different residential attributes, residential regions, and gender, requiring targeted work.

Key words: Birth cohort, EV 71 vaccine, Vaccination, Vaccination rate