Under the Big Tree: Extraordinary Stories from the Movement to End Neglected Tropical Diseases

Under the Big Tree: Extraordinary Stories from the Movement to End Neglected Tropical Diseases is a collection of stories about neglected tropical diseases (NTDs), a group of bacterial and parasitic diseases that affect the world’s 1.5 billion poorest people. Previously, literature on NTDs consisted largely of textbooks, academic papers, and research articles. But engaging more people, from a greater variety of sectors, is helping to lift the burden of NTDs. The book’s purpose is to raise awareness—and to highlight some surprising, inspiring stories about this pivotal moment in which global collaboration, together with greater funding, technological advancements, and historic drug donations, are bringing an end to these diseases. Many countries have eliminated NTDs as a public health problem. However, many more disease-endemic countries remain, primarily in Africa. These countries and the five most prevalent NTDs, (trachoma, schistosomiasis, river blindness, lymphatic filariasis, and intestinal worms, e.g., hookworm), are the focus of Under the Big Tree. At the heart of the book are stories, drawn from hundreds of conversations and interviews with men and women engaged on every side of this monumental worldwide movement.

The reader meets Mwele Malecela, who launched Tanzania’s lymphatic filariasis (LF) program and turned down thousands of dollars in order to protect the program’s integrity; Jacques Sebisaho, who spearheaded a program on the island of Idwji, in the eastern Democratic Republic of Congo, to address not only NTDs but all health care; Michael Kremer, an American economist whose research contributed to knowledge widely accepted today—that deworming children leads to higher earning potential later in life; and dozens more.

There is the story of ivermectin, a drug used to treat and prevent river blindness, a disease that can cause blindness and/or devastating skin disease which includes intense, relentless itching. Prior to ivermectin, no remedy existed for river blindness. In 1974, Robert McNamara, president of the World Bank, launched the Onchocerciasis Control Program (OCP) to spray larvicide on rivers throughout West Africa, killing larvae of the flies that transmit the disease-causing parasite. The same year, from a scoop of soil taken near a golf course in Japan, microorganisms were extracted and sent to Merck Sharp and Dohme (MSD) in New Jersey. Scientists there, led by William C. Campbell, realized that one of the microorganisms was an extremely powerful antibiotic, which they named ivermectin. In 1984, Ivomec was the number one selling pharmaceutical drug for livestock, effective against dozens of animal parasites and bacteria. (If you have ever given a dog a heartworm pill, you have likely handled ivermectin.) Dr. Campbell suggested testing ivermectin against river blindness. The drug was safe, stable, and highly effective. Just as OCP was approaching its geographical limits, Merck’s CEO, Roy Vagelos, announced that Merck would donate ivermectin to countries endemic with river blindness, “as much as needed, for as long as needed.” The commitment was a milestone not only for river blindness but for inspiring drug donations by other pharmaceutical companies. But how could ivermectin reach remote villages that badly needed it? The solution, which resulted in soaring coverage, was Community Directed Treatment with Ivermectin, by which villagers controlled the drug’s distribution.

As of December 2018, WHO has verified the elimination of river blindness in Colombia, Ecuador, Guatemala, and Mexico. The elimination of trachoma and LF as public health problems has been validated in ten countries. As Under the Big Tree’s chapter one concludes:

With much success behind us, and more work to do, we are at a tipping point for NTDs. What will the future be? It could be this: These diseases plagued humans for thousands of years. Then, following radical advancements in medicine, technology, and global collaboration, they didn’t.

Ellen Agler is the CEO of the END Fund. Mojie Crigler is the author of Get Me Through Tomorrow: A Sister's Memoir of Brain Injury and Revival. Together, they are the authors of Under the Big Tree: Extraordinary Stories from the Movement to End Neglected Tropical Diseases.