The impact of immunization on the association between poverty and child survival: Evidence from Kassena-Nankana District of northern Ghana

Background: Research conducted in Africa has consistently demonstrated that parental poverty and low educational attainment adversely affect child survival. Research conducted elsewhere has demonstrated that low-cost vaccines against preventable diseases reduce childhood mortality. Therefore, the extension of vaccination to impoverished populations is widely assumed to diminish equity effects. Recent evidence that childhood mortality is increasing in many countries where vaccination programmes are active challenges this assumption. Data and methods: This paper marshals data from accurate and complete immunization records and survival histories for 18,368 children younger than five years in a rural northern Ghanaian population that is generally impoverished, but where family wealth and parental educational differentials exist nonetheless. Time-conditional Weibull hazard models are estimated to test the hypothesis that childhood immunization offsets the detrimental effects of poverty and low educational attainment. Conclusions: Findings show that the adverse effects of poverty disappear and that the effects of educational attainment are reduced in survival models that control for immunization status. This finding lends empirical support to policies that promote immunization as a strategic component of poverty-reduction programmes.