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Timeliness of Routine Vaccination, Catch-Up Completion, and Immune Function in Chinese Children with Special
Yuyuan Zeng1,2, Xihan Li3, Yu Tian2
1Capital Institute of Pediatrics, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100020, China.
Insights
Children with special healthcare needs in China have significantly lower on-time vaccination rates for national immunization program vaccines. Barriers like caregiver concerns and staff hesitancy hinder catch-up immunizations, impacting immune function.
Area of Science:
- Pediatric Health
- Immunology
- Public Health Policy
Background:
- Children with special healthcare needs (CSHCNs) in China experience significant challenges in receiving timely immunizations.
- Limited data exist on vaccination disparities across different disease groups and vaccine types, as well as on immune function in this population.
Purpose of the Study:
- To evaluate timely vaccination rates and catch-up completion for National Immunization Program (NIP) vaccines among CSHCNs in China.
- To compare immune indices in CSHCNs with established pediatric reference ranges.
- To identify barriers to vaccination and factors influencing immunization status.
Main Methods:
- A retrospective cohort study utilized linked electronic medical records, vaccination records, and follow-up questionnaires.
- Timely vaccination was assessed against NIP dose definitions, and catch-up completion was evaluated.
- Cellular, humoral, and complement immune indices were compared to pediatric reference ranges using statistical analyses (ANOVA, Kruskal-Wallis, chi-square, Fisher's exact tests).
Main Results:
- Timely vaccination rates for all NIP vaccines were significantly lower than national benchmarks (p < 0.001), with Japanese encephalitis virus (JE) and measles-containing vaccine (MCV) showing the lowest completion.
- Caregiver concerns and healthcare provider hesitancy were key barriers to catch-up vaccinations.
- Immunoglobulin A (IgA) and IgG levels were lower in infants with neonatal/perinatal and infectious disorders compared to those with neurological and immune disorders (p < 0.05).
Conclusions:
- CSHCNs in China face substantial immunization barriers, with significant variation in timeliness and catch-up rates depending on vaccine and underlying condition.
- Neonatal/perinatal disorders are disproportionately associated with early-life vaccination delays.
- Improved vaccination coverage requires disease-specific guidelines, enhanced clinic coordination, immunological monitoring, and supportive policies for this vulnerable group.
Background:
Children with special healthcare needs (CSHCNs) face persistent barriers to timely immunization in China, but comparative evidence across disease groups and vaccines, and data on immune function, are limited.
Methods:
We conducted a retrospective cohort study linking electronic medical records, vaccination records, and a structured telephone and questionnaire follow-up. We estimated timely vaccination by National Immunization Program (NIP) dose definitions, assessed catch-up completion at follow-up, and compared cellular/humoral/complement immune indices with published pediatric reference ranges. Group differences used ANOVA/Kruskal-Wallis and chi-square (χ2)/Fisher's exact tests with Bonferroni correction.
Results:
Timely vaccination was lower than the national healthy child benchmarks for all NIP vaccines (all p < 0.001); the Japanese encephalitis virus (JE; 24.0%) and measles-containing vaccine (MCV; 25.9%) had the lowest timely completion. A subset of CSHCNs did not receive recommended catch-up vaccinations, primarily due to persistent caregivers' concern and point of vaccination (POV) staff's hesitancy. Delays clustered in neonatal/perinatal disorders for Bacillus Calmette-Guérin (BCG) and hepatitis B vaccine, dose 1 (HepB1). Catch-up completion was highest for hepatitis B vaccine, dose 3 (HepB3) (86.3%) and BCG (81.8%), and lowest for the diphtheria and tetanus vaccine (DT) (49.4%); MCV2 completion was particularly low in hematological diseases. Immunoglobulin A (IgA) and immunoglobulin G (IgG) concentrations were significantly lower in neonatal/perinatal disorders and infectious disease groups versus neurological and immune disorder groups (p < 0.05). No severe adverse events were reported after catch-up.
Conclusions:
CSHCNs in China face substantial barriers to timely NIP immunization. Timeliness and catch-up vary substantially by vaccine and underlying condition; neonatal/perinatal disorders contribute disproportionately to early-life delays. Disease-specific guidance, strengthened POV-specialist clinic coordination, immunological monitoring, and supportive policies could improve the vaccination coverage and effectiveness in this vulnerable population.
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