Abstract

Background: Inequitable access to vaccinations contributes to significant social gradients in health outcomes for developing countries. In Ethiopia, where poor child health status arises mainly from preventable diseases, childhood immunization programs based on the WHO guidelines have been operational since 1988.
Aims: We examined whether there was any evidence of socio-economic inequality in Ethiopian childhood vaccination coverage at three survey time-points of 2005, 2011 and 2016 and the extent of any trends or changes over the same time period.

Methods: The distribution of childhood immunization coverage was analyzed according to economic status using Lorenz curve derived Gini-coefficients on Ethiopia’s Demographic and Health Survey (EDHS) data from 2005, 2011 and 2016. Specifically, fully immunized status was analyzed according to household income quintile.

Results: Gini-coefficients for fully immunized for the three survey years of 2005, 2011 and 2016 were 0.25, 0.29 and 0.24 respectively. While these values remain just within the margin of preferred equality status of below 0.3, they are at the margin of equality status and variable over time. Visual inspection of the Lorenz curve plots shows clear departures from perfect equality.

Conclusion: While WHO decreed inequality ‘alert levels’ were not exceeded in any of the survey years analyzed, the clear and variable social gradient for fully vaccinated status merits close ongoing monitoring, given the risks of highly infectious childhood diseases. More generally, the combined use of Gini-coefficients and Lorenz curve plots is a powerful tool to interrogate vaccination coverage variability by social group.

Keywords: -Ethiopia, Childhood immunization coverage, inequality, household income status, Gini Coefficient, Lorenz Curve