Reaching the Criteria to Stop Onchocerciasis Mass Drug Administration: Ethiopia, Nigeria, and Uganda Pave the Way

Part of the Act to End NTDS | East technical brief series
June 2021.

To eliminate human onchocerciasis transmission of the filarial parasite Onchocerca volvulus (OV), endemic countries undertake a multi-step process to:

1. Identify focus areas with endemic onchocerciasis transmission,
2. Treat people at risk of OV infection within endemic ‘foci’ using mass drug administration (MDA) for at least 13 years of annual treatment with the microfilaricide ivermectin to suppress transmission,
3. Conduct post-treatment surveillance (PTS) after stopping MDA for a minimum of 3–5 years to confirm the interruption of transmission, and
4. Conduct post-elimination surveillance to confirm that transmission has been permanently interrupted.

This brief describes how Ethiopia, Nigeria, and Uganda addressed these steps, providing examples for other country programs working to stop OV MDA.