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.