Beyond one-size-fits-all: alternative and integrated strategies to accelerate onchocerciasis elimination in challenging transmission settings

Onchocerciasis is a parasitic disease transmitted by blackflies, with a global target for elimination of transmission (EOT) to be verified in at least 12 countries by 2030. Historical vector control and mass drug administration (MDA) with ivermectin have driven substantial progress, including WHO successful verification of EOT in four American countries and, in 2025, Niger as the first in Africa. Yet, transmission persists after decades of control in some historically highly endemic areas. Field surveillance and transmission modelling suggest that even high-coverage biannual treatment may be insufficient where pre-control prevalence was high and blackfly biting remains intense. Progress may also be constrained by groups ineligible for MDA, systematic non-participation and Loa loa co-endemicity. Accelerating EOT may therefore require moving beyond a uniform MDA model towards context-specific, integrated intervention packages. These may combine established methods, such as intensified MDA and focal larviciding, with context-specific or emerging options. These include more potent microfilaricidal treatment with moxidectin, focal anti- Wolbachia macrofilaricidal regimens, test-and-not-treat approaches in L. loa co-endemic areas, and community-led vector control, such as slash-and-clear where ecologically suitable. Transmission modelling can help target intensification and interpret surveillance evidence for stop-MDA decisions. Onchocerciasis-associated epilepsy provides an additional public health rationale for accelerating elimination and, where its burden is substantial, for considering neurological outcomes as secondary measures of programme impact. Strategy selection for reaching EOT in challenging transmission settings should account for pre-control endemicity, vector ecology, human mobility, programme capacity, financing, community acceptability and sustainability, alongside continued surveillance to assess progress and detect any recrudescence.