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Published on: October 1, 2007
Delayed Vaccination and Related Predictors among Infants
J Poorolajal1, S Khazaei, Z Kousehlou
1Research Center for Health Sciences and Department of Epidemiology & Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran ; Dept. of Epidemiology & Biostatistics, School of Public Health, Hamadan University of Medical Sciences, Hamadan, Iran.
Many infants experienced delayed vaccinations despite high overall coverage. Factors like urban residence and maternal education influenced vaccination timeliness, highlighting challenges in immunization programs.
Area of Science:
- Public Health
- Epidemiology
- Pediatrics
Background:
- Vaccination status is often assessed by coverage, not timeliness.
- Delayed infant immunization is a critical public health concern.
- Understanding predictors of vaccination delay is essential for program improvement.
Purpose of the Study:
- To evaluate delayed infant vaccination.
- To identify factors influencing vaccination timeliness.
- To inform immunization program strategies.
Main Methods:
- Cross-sectional study in Hamadan Province, Iran (June-September 2011).
- 2460 children aged 12-24 months recruited via stratified cluster random sampling.
- Data collected from vaccination cards and interviews.
Main Results:
- Infant vaccination coverage exceeded 99.4% for all vaccines.
- 42%-67.6% of infants received vaccines with delays.
- Delay was associated with urban areas, higher maternal education, and later-infancy vaccines.
Conclusions:
- High vaccination coverage does not preclude significant vaccination delays.
- Addressing vaccination timeliness requires targeted interventions.
- Identifying predictors of delay can guide policy for effective immunization programs.
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