Challenges in implementing ivermectin-based mass drug administration for onchocerciasis
Background
Onchocerciasis (river blindness) remains a neglected tropical disease and a major public health burden in sub-Saharan Africa and parts of South America. Despite the proven efficacy of ivermectin, persistent transmission in these regions signals substantial implementation challenges in mass drug administration (MDA) programmes. The WHO's 2009 goal to eliminate the disease underscores the urgent need to address these barriers.
Methods
A systematic literature search was conducted in October 2024 to identify challenges in implementing ivermectin-based MDA programmes for onchocerciasis. MEDLINE, Web of Science Core Collection, CINAHL, and Cochrane Library were searched, along with grey literature via Google Scholar and the WHO website (who.int) for English publications from January 1991 onward. Identified challenges were conceptualised using the WHO Building Blocks Framework and the Social Ecological Model (SEM). Data were analysed descriptively.
Results
Out of 1,459 identified records, 123 articles met the inclusion criteria and were analysed. Reported challenges are primarily related to the Service Delivery category of the WHO Building Blocks Framework, including difficulties in achieving adequate ivermectin coverage and logistical barriers faced by community drug distributors. The Individual Influences category of the SEM highlighted personal beliefs and misconceptions, such as distrust in modern medicine, which hindered participation in MDA.
Conclusions
Systemic and individual-level challenges impede onchocerciasis elimination efforts. A holistic approach is required, integrating improvements in health system delivery with strategies to engage and educate affected communities. Overcoming logistical barriers and addressing cultural beliefs are crucial steps in increasing the participation and success of mass drug administration programmes. Key messages • Health system and individual behavioral challenges hinder onchocerciasis control, including logistical barriers in drug distribution and negative beliefs impacting participation. • A holistic approach is needed, combining improvements in health system delivery with strategies to engage and educate affected communities, to achieve successful onchocerciasis elimination.