A second risk to vitamin A supplementation programs as polio winds down is in regards to reported coverage data [15]. Polio has provided a mechanism for reporting nationwide data on supplements given for vitamin A in countries and as we near the endgame of polio, there is a risk that both doses of vitamin A supplements will reduce and that data quality and reporting will decrease.
One limitation to our report is the data available for vitamin A deficiency, supplementation approaches and coverage is limited and several years old and therefore, we do not have an accurate understanding of the prevalence of vitamin A deficiency in the five countries reviewed in this paper, and whether the combination of polio and vitamin A supplementation has affected it. However the processes that these five countries have followed to leverage polio for vitamin A supplementation offer important lessons that need to be shared.