Diphtheria Vaccination Coverage and Correlation With Multidimensional Poverty Among Children in Nigeria

Nigeria has witnessed recurrent outbreaks of diphtheria in recent times. This study measured the prevalence of diphtheria-pertussis-tetanus (DPT) vaccination coverage among children aged 12-23 months and its correlation with multidimensional poverty index (MPI) across the 36 Nigeria's states and the federal capital territory.

State-level data for DPT vaccination coverage rates and MPI were obtained from the 2021 Multiple Indicator Cluster Survey (MICS)/National Immunization Coverage Survey (NICS) and National Bureau of Statistics, respectively. The correlation between MPI and diphtheria vaccination coverage was examined using SPSS V.28, and alpha level was set to 0.05.

DPT vaccination coverage among children aged 12-23 months is suboptimal at 56%. DPT full vaccination coverage is higher in Southern states than Northern states; all states with ≥80% coverage are in Southern Nigeria, whereas all states with ≤50% coverage are in Northern Nigeria, except for Ogun state (41.3%). Partial DPT vaccination is also higher among Northern states, with Borno state having the highest partial DPT vaccination rate at 27.8%, whereas Ebonyi state had the lowest (0.4%). States with higher MPI had higher proportions of partially vaccinated and unvaccinated children. There is a statistically significant negative correlation between MPI and DPT full vaccination coverage (r = -0.534, p = <0.001).

DPT vaccination coverage is still low in Nigeria. Northern states had lower vaccination coverage than Southern states. There is a significant negative correlation between DPT vaccination coverage and MPI. This study calls for implementing effective strategies to improve vaccination coverage at a national level while focusing on states with high levels of multidimensional poverty.