Background: Measles-containing vaccines (MCVs) and pneumococcal conjugate vaccines (PCVs) can prevent a large proportion of infant deaths and are recommended by international organizations for inclusion in pediatric immunization schedules. In China, MCV but not PCV is publically funded and access to vaccination may be limited among nonlocals, who are rural migrants to cities. In this study, we estimate the proportion of Shanghai children with on-time MCV and PCV administration, compare vaccination in nonlocals versus locals and assess the impact of township-level characteristics on vaccination outcomes.
Methods: Data from children in the Shanghai Immunization Program Information System were linked to township-level data from the 2010 China Census. We used generalized estimating equations with logistic regression models to assess the impact of residency and township-level predictors on on-time MCV and PCV administration.
Results: Nonlocals had lower vaccination levels than locals. Compared with locals, nonlocals had 0.50 times the odds of MCV dose 1 by 9 months [95% confidence interval (CI): 0.47, 0.53], 0.42 times the odds of MCV dose 2 by 24 months (95% CI: 0.39, 0.45), 0.37 times the odds of PCV by 9 months of age (95% CI: 0.33, 0.42) and 0.41 times the odds of PCV by 24 months of age (95% CI: 0.37, 0.45). Overall, children had less on-time MCV and PCV administration in nonlocal-majority than local-majority townships.
Conclusions: Late vaccination negatively impacts disease control efforts in Shanghai. Nonlocals, particularly those living in nonlocal-majority townships, should especially be targeted for vaccination in order to improve disease control efforts in Shanghai.