Abstract: Objective To characterize the landscape of non-Expanded Program on Immunization (non-EPI) vaccine administration in Longgang District, Shenzhen, for the period of 2015-2024. Methods Data on non-EPI vaccine administration and the resident population were sourced from the Shenzhen Immunization Program Information Management System and the Longgang District Bureau of Statistics, respectively. Key metrics were calculated, including the total number of doses administered, average annual growth rate, doses per 10 000 population, substitution rate, and the age in months at primary immunization. Joinpoint regression was employed to analyze trends in the rate of doses administered per 10 000 population and the substitution rates. Concurrently, the Mann-Kendall test was utilized to assess temporal trends in the age at primary immunization for specific non-EPI vaccines. Results Between 2015 and 2024, a total of 8.867 2 million non-EPI vaccine doses were administered in Longgang District, accounting for 54.11% of all vaccine administrations and corresponding to a rate of 2 385 doses per 10 000 population. The three non-EPI vaccines with the highest average annual growth rates were the adult bivalent/quadrivalent/9-valent human papillomavirus (HPV) vaccine (133.99%), the adult recombinant/herpes zoster vaccine (RZV/HZV) (87.71%), and the pediatric 13-valent pneumococcal polysaccharide conjugate vaccine (PPCV13) (74.46%). A significant upward trend was observed in the administration rate of non-EPI vaccines per 10 000 population (AAPC=15.51%, 95% CI: 7.23%-24.56%, P<0.05). The aggregate substitution rate for substitutable non-EPI vaccines was 18.16%; notably, the substitution rate for DTaP-containing non-EPI vaccines increased from 9.08% to 41.76%. Statistically significant trends in the age at primary immunization were observed for all six evaluated non-EPI vaccines (all P<0.001). Specifically, the age for Haemophilus influenzae type b (Hib) and Varicella (VarV) vaccines followed a pattern of initial increase followed by a subsequent decrease, whereas the ages for Enterovirus 71 (EV71), Rotavirus (ORV1, ORV5), and PPCV13 vaccines exhibited significant downward trends. Conclusion The utilization of non-EPI vaccines in Longgang District, Shenzhen, demonstrates a consistent upward trajectory. This highlights the escalating importance of strengthening the surveillance and management of non-EPI vaccine programs in the future.

Key words: Non-Expanded Program on Immunization (non-EPI) vaccines, Immunization, Doses administered, Trend analysis