River Blindness in the Americas
Three decades ago, river blindness in the Americas stood as a major concern. However, according to the Pan American Health Organization (PAHO) by the end of February 2023, “the region of the Americas [had] largely eliminated the disease, with remaining local transmission only in some areas of the Amazon.” Following tens of years of efforts, Colombia, Ecuador, Mexico and Guatemala successfully eliminated river blindness between 2013 and 2016, thanks to the work of several key organizations. The near-elimination of river blindness in the Americas has also brought economic benefits by decreasing the financial and social impacts of ill health.

Onchocerciasis/River Blindness

Onchocerciasis, commonly known as river blindness, is a parasitic disease that transmits to humans through the bite of infected Simulium blackflies. These blackflies typically breed in fast-flowing rivers, commonly found in rural areas.

According to the World Health Organization (WHO), symptoms of river blindness can include extreme itching, skin disfiguration and in severe cases, visual impairment. Currently, no vaccine exists to protect against river blindness. However, the ivermectin drug, when administered on a six-month basis for 12 to 15 years, can prevent transmission of the disease.

The Impacts of River Blindness

Classified as a Neglected Tropical Disease, most of the people infected by river blindness (about 99%) live in sub-Saharan Africa, particularly in rural areas that are prone to poverty.

River blindness is a debilitating disease that can hinder human progress in more ways than one. Some of the socio-economic impacts it can have are increasing hunger and poverty, causing vulnerability to other diseases and hindering education.

A study led by Caitlin Dunn and others, published in 2015, states that, in particular, river blindness exacerbates poverty by reducing agricultural yields, increasing medical expenses and decreasing worker productivity. To avoid river blindness infections, in Africa, for example, people resort to relocating to less fertile areas, which reduces their agricultural productivity and impacts overall income.

Those infected by river blindness face higher medical costs, the burden of which pushes people further into poverty through medical debt. Besides the usual symptoms such as severe itching or skin disfiguration, the disease also weakens the immune system, making one more susceptible to other illnesses too. This places a significant financial burden on those living in poverty.

River blindness can also reduce people’s ability to work and earn an income due to fatigue, pain and visual impairment. This leads to lower incomes and impacts children’s learning abilities at school.

Fighting Against River Blindness

One of the first programs with the goal of tackling river blindness began in West Africa in 1974. The Onchocerciasis Control Programme (OCP) underwent implementation in 11 countries including Ghana and Senegal. At first, the program utilized vector control methods such as spraying insecticides in areas where blackflies transmitted river blindness. It later included ivermectin distribution to aid treatment.

According to the WHO, the OCP “relieved 40 million people from infection, prevented blindness in 600,000 people and ensured that 18 million children were born free from the threat of the disease and blindness.” Furthermore, people reclaimed “25 million hectares of abandoned arable land… for settlement and agricultural production, capable of feeding 17 million people annually,” the WHO website says.

In an effort to bring forth similar results in the Americas, the Onchocerciasis Elimination Program of the Americas began in 1992. OEPA’s main goal was to halt the transmission of river blindness in 13 endemic areas via mass drug administration of ivermectin. The program received great support from the Carter Center, the Pan American Health Organization (PAHO), the Centers for Disease Control and Prevention, United States Agency for International Development (USAID) and others.

OEPA and similar initiatives saw significant success, according to the Carter Center. Overall, 11 of the 13 endemic areas in the Americas have successfully eliminated river blindness transmission. In 2013, WHO declared Colombia the first country in the world to be free of the disease. Ecuador, Mexico and Guatemala followed soon after.

Looking Ahead

The WHO estimates that river blindness in the Americas currently still affects 28,000 Yanomami Indigenous people who live in parts of the Amazon between Brazil and Venezuela. They continue to receive ivermectin treatments via OEPA.

River blindness elimination programs have seen great success. The programs not only combat diseases but also improve the productivity and quality of life of people living in poverty. According to the World Bank, programs like OCP and OEPA have an economic rate of return of more than 15% annually. Therefore, contributing to the fight against river blindness can mean investing in poverty reduction and economic growth.

– Siddhant Bhatnagar
Photo: Flickr