Work

Evaluating the impact of different MMR vaccination strategies on mumps incidence in Shapingba, China:An interrupted time series analysis

Year: 2025

Type: article

Abstract: BACKGROUND: Shapingba District has consistently experienced a high incidence of mumps. China's Expanded Programme on Immunization (EPI) introduced one-dose measles, mumps, and rubella combined attenuated live (MMR) vaccine in 2008 and expanded to two-dose in 2020, but the impact of these sequential policies remains understudied. OBJECTIVE: To evaluate mumps incidence changes following implementation of one-dose and two-dose MMR vaccination strategies in Shapingba District. METHOD: Using interrupted time-series analysis with quasi-Poisson generalized linear models, we analyzed monthly mumps incidence across three periods: the voluntary self-funded mumps vaccine period (January 2004 to December 2010), the one-dose MMR vaccination period (January 2011 to May 2022), and the two-dose MMR vaccination period (June 2022 to December 2024). Age-stratified and temporal lag analyses were performed. RESULTS: Among 10,021 reported cases (2004-2024), annual average incidence decreased from 75.16/100,000 (voluntary period) to 48.17/100,000 (one-dose) and 9.14/100,000 (two-dose) (P < 0.001). Following one-dose MMR introduction, incidence declined 1.0 % monthly (IRR = 0.990, P < 0.001) without immediate level change. The protective effect exhibited a lag period, with significant level reductions emerging from the seventh year onward (IRR = 0.819, P = 0.017). Age-stratified analysis revealed the greatest benefit in the 0-4 years group, with a 2.73 % monthly decline (P < 0.001) after the one-dose introduction. Two-dose MMR implementation showed neither significant immediate level change nor additional trend effects. CONCLUSION: One-dose MMR vaccination achieved substantial long-term mumps reduction in Shapingba District, particularly in younger children. While two-dose implementation shows early promise, longer follow-up is needed for comprehensive evaluation. These findings support the effectiveness of MMR inclusion in China's EPI and inform vaccination policy for high-incidence regions.

Source: Vaccine

DOI: 10.1016/j.vaccine.2025.127885

Authors: Jianchao Shao, Bo Yang, Shurong Feng, Qian Zhi, Shudan Liu

Institution: Chongqing Medical University

Language: English

Topic: Virology and Viral Diseases

Subfield: Epidemiology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: hybrid

Estimated APC paid: $3,620