Comparative assessment of immunization coverage of migrant children between national immunization program vaccines...

This study aimed to describe the disparities in immunization coverage between National Immunization Program (NIP) vaccines and non-NIP vaccines in Yiwu and to identify potential determinants. A face-to-face interview-based questionnaire survey among 423 migrant children born from 1 June 2010 to 31 May 2013 was conducted. Immunization coverage was estimated according to the vaccines scheduled at different age, the birth cohorts, and socio- demographic characteristics. Single-level logistic regression analysis was applied to identify the determinants of coverage of non-NIP vaccines. We found that NIP vaccines recorded higher immunization coverage compared with non-NIP vaccines (87.9100%- vs 0%-74.8%). Among the non-NIP vaccines, varicella vaccine (VarV) recorded the highest coverage of 85.4%, which was introduced in 1998; while 7-valent pneumococcal conjugate vaccine(PCV7) recorded the lowest coverage of 0% for primary series, which was introduced recently. Lower coverage rate of non-NIP vaccines was significantly associated with more siblings in household, shorter duration of living in the surveyed areas, lower family income, mother with a job, mother with poor awareness of vaccination, and mother with lower education level. We found the immunization coverage rate of non-NIP vaccines was significant lower than that of NIP vaccines. Expansion of NIP to include non-NIP vaccines can provide better protection against the vaccine preventable diseases through increased immunization coverage.