Modelling analyses (https://doi.org/10.1371/journal.pntd.0003938) have shown that an onchocerciasis vaccine will have a substantial impact in a range of endemicity scenarios and will markedly reduce microfilarial load in those under 20 years of age. This has important implications as studies have highlighted the increased risk of developing onchocerciasis related morbidity and mortality in individuals who acquire heavy infections in early life.
It is clear that a vaccine would have a beneficial impact by reducing onchocerciasis-related disease burden in these populations. Furthermore, a vaccine could markedly decrease the chance of recrudescence of onchocerciasis in areas where mass drug treatment has stopped, or failed.
A vaccine would protect the substantial investments made by present and past onchocerciasis control programmes (together, the Onchocerciasis Control Programme in West Africa (OCP) and APOC have cost over US$1 billion), by reducing the chance of disease recrudescence and the possible spread of ivermectin resistance.