# Reaching the last mile with ivermectin mass drug administration against onchocerciasis: The case of Kwanware-Ottou persistent transmission focus in the Wenchi health district of Ghana

## TL;DR

This study shows how a tailored approach improved ivermectin treatment coverage in a hard-to-reach area of Ghana, helping to combat persistent onchocerciasis transmission.

## Contribution

The study introduces a scalable, locally adapted strategy to enhance CDTI effectiveness in persistent onchocerciasis transmission areas.

## Key findings

- Treatment coverage increased from 70.8% to 88.2% after implementing the action plan.
- Seven out of eight previously underperforming communities exceeded the 65% coverage threshold.
- The intervention improved data quality, community engagement, and directly observed treatment adherence.

## Abstract

Despite over two decades of Community-Directed Treatment with Ivermectin (CDTI), onchocerciasis transmission persists in localized pockets in Ghana, particularly in the Kwanware-Ottou community within the Wenchi Health District. This study trialled a scalable approach to identifying context-specific barriers and solutions for improving CDTI effectiveness.

A mixed-methods approach was employed, including Geographical Information System mapping, community consultation, census and treatment coverage evaluation, and qualitative assessments. These informed the participatory development of an Action Plan, which was implemented and evaluated across three sub-districts. Key challenges identified and addressed included poor data quality, high population mobility, remote settlements with accessibility issues, limited awareness, and inadequate number and deployment of community drug distributors. As a result, therapeutic coverage increased from 70.8% to 88.2. Seven out of eight communities with pre-intervention coverage below the recommended 65% threshold not only achieved but exceeded this target. Ultimately, all communities met the coverage goal. The intervention also improved data accuracy and quality, community engagement, and adherence to directly observed treatment, while addressing systemic gaps in CDTI delivery.

This study demonstrates that a coordinated, locally adapted stimulus package can significantly enhance CDTI performance in areas of persistent onchocerciasis transmission. The approach presents a scalable model for similar endemic settings and aligns with the World Health Organization’s 2021–2030 Roadmap for the elimination of Neglected Tropical Diseases.

Onchocerciasis, or river blindness, is a parasitic disease transmitted by blackflies. It remains a public health challenge in parts of Ghana despite decades of community treatment with ivermectin. In Kwanware-Ottou area within the Wenchi Health District, transmission has persisted for over 27 years. This study investigated why onchocerciasis continues to spread in this region and tested new strategies to improve treatment coverage. Using satellite imagery, community mapping and interviews, we identified hard-to-reach settlements and population groups often missed during treatment. A locally tailored action plan was developed and implemented with strong community involvement. Results showed a significant increase in treatment coverage and improved community participation. This approach demonstrates how combining local knowledge, technology, and participatory planning can help overcome persistent disease transmission. These findings offer a practical model for other regions facing similar challenges in eliminating onchocerciasis and other neglected tropical diseases.