Niger’s Defeat of River Blindness 

The World Health Organization has verified Niger as the first country in Africa to eliminate river blindness, a debilitating disease that affects an estimated 21 million people worldwide. This milestone shows the power of collaboration between government, non-profit organizations, and the private sector in fighting neglected tropical diseases and lays out a blueprint for other countries in the region to follow.

by Zanele Mji

Dr Daniel Boakye remembers witnessing the dire effects of onchocerciasis during a trip to Ghana in the 1970s as a student entomologist. He was studying blackflies, which spread the skin and eye disease more commonly known as river blindness. At the time, the debilitating disease was ravaging West Africa. In some of the most affected villages, more than half of all men aged 20 and above had become visually impaired or gone blind.

In Ghana’s rural villages located near fast-flowing rivers and streams, the blackfly’s breeding ground, life was at a standstill. Without enough able-bodied people to tend the fields, families went hungry. Children dropped out of school to care for blind relatives. Where there was river blindness, there was poverty. Touched by what he saw, Boakye has spent the 50 years since then working to tackle the disease. “I’ve been chasing flies all my life,” he said.

Now the Senior Technical Advisor for elimination of onchocerciasis at the END Fund, a philanthropic fund focused on ending neglected tropical diseases (NTDs), Boakye is a leader in the effort to reduce the spread of river blindness in Africa. Working with the World Health Organization (WHO), global health organizations, and the government, his team helped Niger become the first country in Africa to declare the total elimination of onchocerciasis. The WHO officially recognized that achievement on World NTD Day in January.

The path leading to that huge milestone now serves as a blueprint for other countries in the region to follow. “It was amazing to see the villages come back to life,” said Boakye. “People reoccupied fertile farmlands they had abandoned because of the disease. Adults could fend for their families and children went back to school.”

Neglected Tropical Diseases Affect 1 Billion People

River blindness is caused by repeated bites from blackflies infected with the Onchocerca volvulus parasitic worm. Once introduced into the bloodstream, the worm can grow to almost 1 m in length and produces millions of larvae that migrate to the skin and eyes. Symptoms include extreme itching and, in one third of cases, tunnel vision and eventually blindness.

The disease is one among a group of diverse conditions known as NTDs, which cause a range of health, social, and economic problems. Together, they are estimated to affect more than 1 billion people, but still rank very low in the priorities of policymakers around the world. 

According to WHO, more than 99% of people infected with river blindness live in just 31 African countries. While a few of those countries, such as Niger, have managed to find the political will to tackle the disease, many are still struggling. In neighboring Nigeria, for example, river blindness affects 32 of the country’s 36 states.

Anita Gwom is Director of NTDs at Sightsavers, a non-profit organization that provides disease treatment for rural communities. When she visits villages in Nigeria, she sees children having to skip school to lead their blind grandparents around. Income levels suffer, especially during the rainy season, when people avoid working outside for fear of being bitten by blackflies. “Fishermen know that when they go to the river, they will be bitten,” said Gwom. “When you talk to them, they will tell you they have been bitten by the fly multiple times.” 

Gwom said it takes 10 – 15 years of focused interventions to break the transmission of river blindness in an endemic community. And climate change is making that harder as frequent flooding expands the blackfly breeding areas. Non-profit organizations are doing what they can. In the six Nigerian states in which Sightsavers works, it has already given out 100 billion treatments against river blindness. But it’s not nearly enough, said Gwom. “There is donor fatigue. Government support is usually very poor. Not prioritizing NTDs is an issue,” she said.

Game-changing Partnerships

Partnerships between government, NGOs, and private sector funders are crucial in the fight against NTDs. But, it can be difficult to predict what will bring those groups together in a unified effort to tackle a specific disease. For visceral leishmaniasis (VL), a deadly disease caused by parasites transmitted by the bite of infected female sandflies, it was the combination of a roadmap and a framework. 

An estimated 30,000 new cases of VL occur worldwide annually. Most of these are in Brazil, India, and east Africa, where the disease’s epidemiology — widely spread with frequent outbreaks — make it especially difficult to track and treat. “Also, tackling VL in east Africa is mainly dependent on external support for implementation,” said Saurabh Jain, a scientist and Focal Point for VL at WHO.

In 2021, the WHO released its new NTD roadmap, which sets global targets and milestones to prevent, control, and eliminate or eradicate 20 diseases and disease groups by 2030. Three years later, at the request of stakeholders, WHO launched a strategic framework for the elimination of VL as a public health problem in eastern Africa, along with a call to action known as the Nairobi Declaration. “This triggered a reinvigorated interest and commitment by all the stakeholders to work toward VL elimination in that part of the world — and that requires financial support,” said Jain. 

In Niger’s battle against river blindness, it was the discovery of a new use for a veterinary drug that spurred various partners into collective action. Starting in the 1970s, Boakye and his colleagues at the WHO’s Onchocerciasis Control Programme in West Africa (OCP) were focused on vector control, using chemicals and other techniques to kill the blackflies and their larvae. Then, in 1975, researchers found that ivermectin, which is mainly used to treat heartworm in animals, was extremely effective at killing the Onchocerca volvulus worm inside the human body. “It was a total game changer. Using the drug for mass treatment was cheaper and more effective than vector control alone,” Boakye said.

Through a collaboration with WHO and the governments of Niger and other affected countries in Africa, pharmaceutical manufacturer Merck & Co. made ivermectin freely and widely available for as long as it was needed. Under the OCP and the World Bank Group’s Onchocerciasis Control Program, the African countries where river blindness is endemic committed to cross-border cooperation on their shared goal of eliminating the transmission of the disease using a combination of ivermectin treatment and vector control.

Various other global organizations played a part, such as the United States Agency for International Development (USAID) and the Task Force for Global Health. And vital funding also came from the Reaching the Last Mile Fund, which mobilized $100 million over 10 years to fight river blindness in seven countries, including Niger. “Many countries have put a lot of work into integrating treatment into their health systems, but funds like this help with the last mile of effort, such as mainstreaming surveillance of the disease and gathering the documentation to demonstrate elimination,” said Dr Maria Rebollo Polo, Lead of the Global Onchocerciasis Elimination Program at the WHO.

With all of these elements in place, river blindness rates in Niger fell from around 60% in the 1970s to 0.02% by 2002 and continued to fall. Now that Niger has received WHO verification as the first African country to have eliminated the disease, it joins an exclusive club – only Colombia, Ecuador, Mexico, and Guatemala have been verified as onchocerciasis-free by the WHO so far. But, Boakye said, they could soon have company, with Senegal, Mali, Benin, and Togo all close to achieving the same status.

After five decades of chasing flies, Boakye is celebrating these milestones, but has not slowed down his work. “It’s exciting, I didn’t always believe this was possible,” he said. “We’ve got to keep going, keep overcoming delays and obstacles on the road to total elimination of onchocerciasis transmission across the continent.”

Read further: WHO’s Roadmap for Controlling or Eliminating 20 Neglected Tropical Diseases