Trends and patterns of under-5 vaccination in Nigeria, 1990-2008: what manner of progress?

Despite efforts towards reducing childhood morbidity and mortality, Nigeria ranks among countries with the highest rates of vaccine-preventable diseases including tuberculosis, poliomyelitis, measles, diphtheria, pertussis and tetanus. These efforts include regular rounds of immunization days and routine exercises. The government of Nigeria periodically undertakes National Demographic and Health (NDH) surveys, which tap information on various health indices including vaccination coverage. Limited studies have used the NDHS data to examine the trends in vaccination coverage for the assessment of successes or failures of the immunization efforts.

This study used four NDH Surveys datasets between 1990 and 2008, which generated child health information including the proportion that had had any or all basic childhood vaccines. A combined total of 44,071 (weighted) children were involved in the study. The trend and pattern of vaccination over 18 years were examined while selected factors were regressed to obtain predictors of child vaccinations in Nigeria.

The most recent survey (2008) reported more complete vaccination apart from 1990, which was said to be inaccurate. In all surveys, children from mothers with higher education, who were delivered in hospitals, lived in urban areas, and whose mothers work outside the home had significantly higher proportions of completed basic vaccination. A lower level of childhood vaccination is observed in the northern parts, while higher rates are observed in the southern parts. More complete vaccination coverage was reported in the 1990 survey, followed by 2008, 1999 and 2003. In addition, children from mothers with higher levels of education, who were delivered in hospitals, who lived in urban areas, and whose mothers work outside the home had significantly higher proportions of completed basic vaccination.

Much more work needs to be done if more children are to be covered and thus reduce vaccine-preventable diseases.