You may have read about ‘ivermectin’ in connection with the COVID-19 pandemic. But when I hear the name of this drug, I always think of one of the world’s biggest public health successes – and it may not be a story you have heard before, because it mostly happened in remote communities in Africa.
Agnes, a pretty young girl living in a rural area of eastern Nigeria, was pregnant, anemic, weak and suffering from terrible skin lesions that she scratched constantly, when she met researcher Uche Amazigo at a clinic in a small Nigerian village in 1991. Their meeting not only changed Agnes’ life – it also eventually changed the lives of millions of people in Africa, through a community-run treatment program that works even in the most challenging and difficult conditions.
The program’s model proved that even the most fragile African health care systems can be supported and strengthened effectively from the bottom up, and that empowering communities to care for their own health can make existing treatments for many diseases available even in the most remote locations.
Uche met Agnes because, while she taught and researched tropical diseases at the University of Nigeria, she visited women in rural areas each week to talk about their lives, nutrition and overall health status. An observant nurse thought Agnes’ skin lesions were caused by the same worm that caused a dreadful disease, river blindness, known scientifically as onchocerciasis, and asked Uche to investigate. Analysis of a snip of Agnes’ skin showed she had small numbers of the same parasites that caused blindness in older people when they migrated to the eye. Agnes’ husband had left her because of the lesions, and many more women in her village had the same skin disease and also were often deserted.
But, at that time, onchocerciasis control was focused on the areas of Africa where blindness was prevalent – chiefly in West Africa, where it caused economic losses estimated at US$30 million. River blindness was the world’s fourth leading cause of preventable blindness. But in 1974, when four UN agencies began the Onchocerciasis Control Programme (OCP) in West Africa, no effective drug treatments were available and so the program concentrated on aerial spraying to kill blackfly larvae in rivers which spread the disease to the worm.
Researchers looked for a treatment that would work. Ivermectin, developed by the US drug giant Merck & Co. in the late 1970s from a microorganism found in soil near a Japanese golf course, was one of many compounds tested by the Special Programme for Research and Training in Tropical Diseases (TDR). It did not kill the adult parasite with one dose, but it did work effectively against the parasite’s infant larvae and thus could form part of an effective control strategy to help people like Agnes.
Merck decided to donate the drug for onchocerciasis control programs for as long as it was needed, and it became the world’s longest-running donation program by a pharmaceutical company, providing billions of tablets to millions of people annually in 33 countries. By the time the program ended in 2015, onchocerciasis control programs in Africa expected to have reached 80 million people with ivermectin.
Once TDR knew it could get ivermectin, the question was how to best use it. Research showed that the skin disease affected many more people and countries across eastern, central and southern Africa than did blindness in West Africa, causing intense inflammation for one to two years, then skin rashes, swelling, inflammation, lesions and intense itching. Women often found themselves socially isolated because of what people called ‘lizard skin’; children could not concentrate in school because of the constant itching.
TDR faced two problems – how to convince policy makers to extend the treatment program beyond the area where blindness was the problem, and how to get the drug to people each year in thousands of remote villages in much of Africa at a reasonable cost?
So TDR turned to a group of African researchers to address that question – finding an ivermectin distribution method that was cheap, worked in some of Africa’s most remote and war-torn areas, and was sustainable over the two decades needed to break transmission of the parasite.
The researchers developed a ‘community-directed treatment’ method that put communities in charge of organizing how they would administer the ivermectin. Health services would provide support but would not tell communities how to do it.
The program adopted that idea, and community-directed treatment with ivermectin was the backbone of the African Programme for Onchocerciasis Control (APOC) when it began operations in 19 countries in eastern, central and southern Africa in 1996. In 1997, APOC formally adopted CDTI, which soon showed itself to be an outstanding success in African health care.
In 2006, for example, 46.2 million people were treated by trained, unpaid drug distributors – people chosen by their community. And one of those distributors was Agnes, whose dramatic life change after ivermectin made her an excellent ambassador for APOC. By 2002, when Uche and Agnes met again, Agnes’ skin lesions had improved, her husband had returned, and she had become a drug distributor in her village – and Uche had become the director of APOC. “I think that was one of the greatest moments in my life, to see her so very happy with her husband, her children, her family,” Uche said.
The importance of community-directed treatment, she explained, was that while effective interventions exist for many diseases, they just do not reach the people who need them most – the poor in remote communities. A Ugandan researcher said CDTI taps into community’s capacities for self-organization to create real, working primary health care; once they knew what to do, they would do it. Some organizations, however, skipped the intensive social mobilization that was necessary at the start, and chose drug distributors themselves. That did not work, because the community would choose someone it trusted as a distributor; outside agencies did not know the community well enough to make such a choice.
Community ownership was key to the amazing success of APOC. It made it possible to distribute ivermectin widely, even in the most remote villages, at low cost, over many years. It brought millions more years of useful life to people all over Africa. It was one of history’s most successful drug distribution programs, and UNESCO called it “one of the most triumphant public health campaigns ever waged in the developing world”.
APOC ended its work in 2015, turning over its responsibilities to health departments in the various countries. But its example shines brightly, and offers at least three key lessons.
Firstly, focusing on ‘neglected’ tropical diseases – as the WHO did – makes possible new private-public partnerships that lead to new discoveries.
Secondly, local researchers will come up with practical delivery strategies because of their local knowledge.
Thirdly, empowering communities to manage their own health is a sustainable, low cost way to build a strong foundation for primary health care in Africa.
Revitalizing health care delivery in sub-Saharan Africa: the potential of community-directed interventions to strengthen health systems. APOC, World Health Organization, 2007.