Objective To analyze the use of non-national immunization program(nNIP) vaccines in Liaoning Province from2018 to 2024, evaluate the current situation of nNIP vaccination in Liaoning Province, and to provide scientific basis for formulating public health policies and optimizing vaccination strategies.Methods The nNIP vaccination data from 2018 to2022 and 2023 to 2024 were extracted through “China Immunization Program Information Management System” and“Liaoning Province Immunization Program Comprehensive Information Platform-Vaccination Information System”, including nNIP vaccine replacement records. Pearson correlation coefficient matrix analysis was performed using SPSS 13.0 software,and descriptive analysis method was used to comprehensively analyze the data.Results From 2018 to 2024, a total of25 726 024 doses of nNIP vaccines were administered in Liaoning Province, with per capita dose of 866 doses per 10 000 people. The per capita doses of nNIP vaccine and the proportion in total doses of all vaccines were increasing year by year.The top three nNIP vaccine varieties used were rabies vaccine for human use(Rab), influenza vaccine(InfV) and varicella attenuated live vaccine(VarV). Among the NIP, poliomyelitis vaccine(PV) showed the highest substitution rate(30. 40%),followed by hepayitis A attenuated live vaccine(HepA-L)(29. 08%) and diphtheria,tetanus and acellular pertussis combined vaccine(DTaP)(16. 37%).Conclusion The importance of nNIP vaccines in public health has become increasingly prominent. As an important part of vaccination, the quality of surveillance needs to be further strengthened. The nNIP vaccines can make up for the lack of NIP vaccine coverage, and can also play an important role when some NIP vaccines are temporarily in short supply. On the basis of optimizing the supply and distribution of NIP vaccines, increasing the level of nNIP vaccination can effectively prevent and control the epidemic of vaccine-preventable infectious diseases.

Objective To evaluate the impact of the inclusion of (MPSV-AC) vaccine in the Expanded Program on Immunization (EPI) on the incidence of meningococcal meningitis. Methods Data on the incidence of meningococcal meningitis in Liaoning from 1995 to 2019 were collected, Interrupted time series (ITS) analysis was used to assess the level and slope change of the incidence of meningococcal meningitis before and after the inclusion of MPSV-AC vaccine in the EPI. Results Before the MPSV-AC vaccine was included in the EPI, the average annual incidence rate of meningococcal meningitis was 0.3442/100 000, the incidence rate showed a descending trend with an annual decrement of 0.0319/100 000. After the MPSV-AC vaccine was included in the EPI, the average annual incidence rate of meningococcal meningitis was 0.0151/100 000 and he incidence of meningococcal meningitis showed a descending trend with an annual decrement of 0.0042/100 000. Conclusion The incidence of meningococcal meningitis reduced after the inclusion of MPSV-AC vaccine in EPI，and the EPI strategy had a continuous effect on the decreasing trend of meningococcal meningitis incidence.

Objective To understand the use of the annual immunization program vaccine in Liaoning Province, and to objectively grasp the consumption coefficient of multi-dose immunization program vaccine, to provide the basis for the annual immunization program vaccine demand. Methods The amount of vaccine used in theimmunization plan of Liaoning Province in 2019 and the actual number of vaccine inoculations were summarized, and the utilization rate of vaccine and the consumption coefficient of vaccine in multiple doses were calculated. Results In 2019, the utilization rate of different varieties of immunization program vaccine was more than 65%, and there was significant difference in the utilization rate among cities (P<0.01). The consumption coefficients of multi-dose vaccination vaccine were 2.33 for DT, 2.26 for BOPV and 2.20 for MPSV-A, respectively. Compared with DT, BOPV and MPSV-A, MPSV-A had the highest scrap rate of 2.87%, followed by BOPV and DT with 1.82% and 0.32%, respectively. Conclusion Vaccine consumption in the multi-dose immunization program is the main factor affecting the accuracy of the annual requirement budget, and vaccine management should be strengthened to achieve reasonable allocation, reduce consumption and avoid waste.