Objective To analyze the current status of influenza vaccination in Liaoning Province from 2014 to 2024, and provide a basis for formulating population influenza prevention and control strategies.Methods The information related to influenza vaccine was collected, and the influenza vaccination data in Liaoning Province were derived through “China Immunization Program Information Management System” and “Liaoning Province Immunization Program Comprehensive Information Platform-Vaccination Information System” to analyze the current situation and characteristics of influenza vaccination from 2014 to 2024.Results From 2014 to 2024, the number of per capita doses of influenza vaccine in Liaoning Province showed an upward trend, reaching 348. 96 doses per 10 000 people in 2023, with a month-on-month increase of119. 40%. The proportion of influenza vaccinations in non-immunization program vaccinations increased from 6. 91% in2018 to 32. 19% in 2023. Starting from 2019, influenza vaccines with different technical routes have been included in the reporting scope. The quadrivalent influenza split vaccine accounted for 67. 40% of the total influenza vaccination of all varieties, and the proportion of vaccination in 2024 was as high as 82. 83%. Regional distribution showed that the number of influenza vaccination doses was the highest in Dalian(1 679 818 doses), followed by Shenyang(1 284 318 doses). The vaccination rate was the highest in Dalian(2. 55%), followed by Benxi(2. 17%) and Shenyang(1. 56%). Influenza vaccination time was mainly concentrated from August to December, accounting for 96. 14% of the annual vaccination times.Conclusion The number of per capita vaccinations of influenza vaccine in Liaoning Province shows a rapid growth trend,which reflects the gradual improvement of public awareness of health and the positive effects of public health interventions.However, there are still low vaccination rates and regional differences. In addition to strengthening publicity and promotion,it is suggested to further improve the overall vaccination rate of influenza vaccine through policy guidance, prevent influenza more efficiently and reduce the burden of diseases.

Objective To understand the utilization of immunization program vaccines in Liaoning Province and evaluate the vaccine management mode, and to provide a scientific basis for optimizing immunization strategies. Methods The vaccine collection data and vaccine administration data of vaccination units (including obstetric clinics) in the province from 2021 to 2024 were collected, and the vaccine utilization rate of immunization program was calculated. SPSS 13.0 software was used for data analysis, and χ² test was used for comparison. A two-sided P value of <0.05 was considered statistically significant. Results (1) From 2021 to 2024, vaccination units and obstetric clinics received a total of 15 993 884 doses of immunization program vaccines, with a total utilization rate of 79.34%. The highest utilization rate was the single-dose vaccine MPSV-AC (94.02%), followed by JE-L (91.92%). The lowest rate of use was the 5-dose strength vaccine MPSV-A (48.12%), followed by the 4-dose strength vaccine DT (63.13%). (2) Comparing MPSV-A and DT in different years, the utilization rate of MPSV-A and DT was the highest in 2021, 59.53% and 67.71%, respectively. From 2021 to 2024, the utilization rate of MPSV-A had a decreasing trend year by year, with the lowest being 38.65% (2024), and the loss coefficient of MPSV-A in each year was higher than that of DT. (3) Comparison of vaccine utilization rates in immunization programs around 2020, the utilization rate of single-dose vaccines increased significantly compared with before, while the utilization rate of multi-dose vaccines decreased compared with before 2020. Conclusion After 2020, the vaccine utilization rate of the immunization program in Liaoning Province has increased significantly, and the optimized vaccine management strategies has achieved remarkable results. Multi-dose vaccines remain highly susceptible to formulation-related factors and vaccination density. It is recommended to formulate precise vaccination strategies to reduce the loss of multi-dose vaccines.

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.