Work

Vaccination coverage by age 24 months among children born in 2020 and 2021 in China, during the COVID-19 pandemic: A study based on the national immunization information system

Year: 2025

Type: article

Abstract: OBJECTIVE: This study aimed to evaluate the vaccination status of the National Immunization Program (NIP) among children born in 2020-2021 in China and assess the impact of the COVID-19 pandemic on vaccination coverage. METHODS: Three counties were randomly selected from each of the provinces of Zhejiang, Chongqing, and Shanxi in China. Vaccination records were retrieved from provincial immunization information systems. Statistical analyses were conducted using descriptive epidemiological methods and chi-square tests to compare vaccination coverage across different regions and birth cohorts. The Kaplan-Meier method was also applied to estimate vaccination coverage at specific ages. RESULTS: Except DTaP4, NIP vaccination coverage for children born in 2020-2021 remained high, exceeding the 90.00 % target. Coverage ranged from 90.09 % for PV3 (95 % CI, 90.07-90.47 %) to 99.21 % for HepB1 (95 % CI, 99.15-99.27 %). However, compared to children born during 2015-2019, coverage for most vaccines (excluding BCG and HepB1) among those born in 2020-2021 significantly declined (all P-values <0.05). Regarding timeliness, the timely vaccination coverage for NIP vaccines ranged from 78.96 % (95 % CI, 78.70-79.25 %) for DTaP4 to 97.74 % (95 % CI, 97.65-97.84 %) for HepB2. The primary reasons for vaccination delays were missed doses (54.9 %) and delayed administration (41.0 %). Significant regional differences in vaccination coverage and timeliness were also observed (all P-values <0.05). CONCLUSIONS: Despite pandemic challenges, China maintained high NIP coverage, though some declines occurred. Regional differences highlight the need for targeted interventions to improve immunization services, ensure timely protection, and address socioeconomic and health resource disparities.

Source: Vaccine

DOI: 10.1016/j.vaccine.2025.127717