Journal article
Timing of children’s vaccinations in 45 low-income and middle-income countries: an analysis of survey data
Summary
Background Vaccinations are often delayed until well after the recommended ages, leaving many children exposed for
longer than they should be. We estimated vaccination coverage at diff erent ages, and delays in administration, in
45 low-income and middle-income countries.
Methods We used data for 217 706 children from Demographic and Health Surveys between 1996 and 2005
(median 2002), which provided data for vaccination of children on the basis of events recorded on vaccination cards
and interviews with mothers, with imputation of missing values and survival analysis. We devised an index combining
coverage and delay.
Findings For vaccinated children, the median of the median delays in the 45 countries was 2·3 weeks (IQR 1·4–4·6)
for bacille Calmette-Guérin (BCG); 2·4 weeks (1·2–3·3) for diphtheria, tetanus, and pertussis (DTP1); 2·7 weeks
(1·7–3·1) for measles-containing vaccine (MCV1); and 6·2 weeks (3·5–8·5) for DTP3. However, in the 12 countries
with the longest delays for each vaccination, at least 25% of the children vaccinated were more than 10 weeks late for
BCG, 8 weeks for DTP1, 11 weeks for MCV1, and 19 weeks for DTP3. Variation within countries was substantial: the
median of the IQRs in the 45 countries for delay in DTP3 was 10·9 weeks, 7·9 weeks for MCV1, 5·4 weeks for BCG,
and 5·3 weeks for DTP1. The median of the national coverage rates for DTP1 increased from 57% in children aged
12 weeks to 88% at 12 months, and for DTP3 from 65% at 12 months to 76% at 3 years.
Interpretation The timeliness of children’s vaccination varies widely between and particularly within countries, and
published yearly estimates of national coverage do not capture these variations. Delayed vaccination could have
important implications for the eff ect of new and established vaccines on the burden of disease.
Authors
Languages
- English
Publication year
2009
Journal
Lancet
Volume
March 20, 2009 DOI:10.1016/S0140- 6736(09)60317-2
Type
Journal article
Categories
- Data
Tags
- Coverage monitoring
- Data quality
- Immunization information systems