Delayed administration of childhood vaccinations in low- and middle-income countries – findings from the third round of the Multiple Indicator Cluster Surveys (MICS3) in 34 countries

Objectives: Many developing countries achieved high coverage for childhood vaccinations. However, research has shown that vaccinations are sometimes administered with substantial delays. We aimed to examine the extent of delays in childhood vaccinations and to examine factors associated with delayed and missing vaccinations. Methods: We used the recent available MICS3 data in 34 countries conducted in 2005 and 2006 (n=113,570). Surveys were conducted among women aged between 15 and 49 years, only information on childhood vaccinations from child health cards was used. The Kaplan-Meier method was used to examine age-appropriate vaccinations and delays in vaccinations. Factors associated with delayed and missing vaccinations were assessed by using multilevel logistic regression analysis. Results: The median fraction of timely administered vaccination across all countries was 65% (Interquartile range, IQR 51.6–71.6) for BCG, 65% (53.8–70.7) for DTP1, 41% (27.1–51.5) for DTP3 and 51% (42.7–62.5) for MCV. The median of the median delays across all countries for BCG was 2.3 weeks (IQR 0.7–5.6), 2.6 weeks (0.7–6.6) for DTP1; 6.4 weeks (2.3–17.3) for DTP3; and 4.2 weeks (1.0–14.0) for MCV. Boys, those living in families with a higher number of children, children living in rural areas and from poorer families were more likely to be vaccinated with delays for DTP vaccine compared to timely vaccinated children. Similar pattern of association was observed for MCV vaccine (except gender and place of residence). A lower economic status was also associated with a higher risk of missing DTP and MCV vaccinations. Conclusions: Vaccinations were often administered with substantial delays. An inclusion of the new indicator „Age-appropriate vaccination“ into the monitoring systems of vaccination services may help to identify delayed vaccinations and therefore, undertake necessary interventions. Further research is needed to examine more deeply factors contributing to delayed vaccination.