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The Mectizan Donation Program Celebrates 35 Years

Published: 15.06.2022
Joni Lawrence Sr. Associate Director Communications, advocacy, and partnerships
Mectizan Donation Program

In October of 1987, Merck & Co., Inc.*, committed to donating Mectizan—as much as needed, for as long as needed—with the goal to help control river blindness (onchocerciasis). In 1998 the donation was expanded to include the elimination of lymphatic filariasis (LF), another neglected tropical disease that overlaps with river blindness in many countries in Africa and in Yemen.
Since its inception, Merck has shipped 11 billion 3mg tablets of Mectizan for the 4.6 billion treatments approved by the Mectizan Donation Program (MDP). In 2021, MDP approved 364 million treatments in 32 countries; the program averages 372 million treatments approved per year.

In the 35 years since, many lessons have been learned and many goals have been accomplished and expanded. What started out as a control program became an elimination program in 2021 with the launch of the WHO 2021-2030 NTD Road Map, which is targeting 12 countries to be verified for elimination of transmission by 2030.

Four countries in Latin America have achieved this.  In Africa, Niger is preparing its dossier to WHO for verification of elimination of transmission and may soon become the first country in Africa to achieve this milestone. This will be a remarkable achievement after decades of elimination efforts in Niger, starting with larviciding with support from WHO’s Onchocerciasis Control Program in the 1970s, which was the frontline intervention until Mectizan was donated in 1987. Several other countries in Africa are close behind.

Another indicator of success includes the number of people who no longer need treatment for river blindness. By the end of 2021, 15.7 million people were living in areas where transmission is suspected to have been interrupted or eliminated, and who no longer need treatment with Mectizan. Post-treatment surveillance for river blindness is underway in areas where there is no LF and will begin in LF co-endemic communities when they are eligible to stop MDA for LF elimination.

This success and progress toward elimination of transmission would not have been possible without Merck’s donation of Mectizan, the commitment of endemic countries, WHO, our NGO partners, the donors, and the research community.

To celebrate 35 years of progress toward river blindness elimination, the Mectizan Donation Program is sharing a short video each month to tell the story. The videos can be seen on the Mectizan Donation Program website: and on Instagram:  Together, we can #StampOutOncho!

*Merck & Co., Inc., Rahway, New Jersey USA, is known as MSD outside the United States and Canada.