Vaccine stockouts and vaccination rate: examination of unique administrative data from Nigeria
Abstract Background Universal access to vaccines is crucial in protecting the population from deadly diseases. This study presents the prevalence of vaccine stockouts in Nigeria and examines the correlation between the vaccine stockouts and vaccine take-up. Methods We use the unique administrative data of monthly vaccine stockouts at each health facility in Nigeria. To evaluate the correlation between the stockouts and the vaccine take-up, the administrative data were merged with the Nigeria Demographic and Health Survey conducted in 2013. We used logistic regression for the correlational study. Results The prevalence of vaccine stockouts in Nigeria is high: 82.7% between 2012 and 2013. We find a negative correlation between vaccine stockouts and vaccine take-up. However, we observe the differential correlational pattern depending on the regional vaccine coverage, which we consider as the proxy of the level of demand for vaccines. Conclusions We find that, while vaccine stockouts are correlated with the low vaccine take-up on average, this negative correlation between stockouts and vaccination rate is observed only in regions with low demand for vaccines. Reducing vaccine stockouts in regions with the low vaccination coverage might be an effective way to increase the overall vaccination rate.