For nearly a century, people have reported mysterious epidemics of permanent paralysis in rural regions of Africa. In 1990, Hans Rosling a Swedish epidemiologist and pop-star statistician, who died of pancreatic cancer earlier this month, linked the malady to cyanide in the staple crop, cassava.
But Rosling would protest if I told you that cassava causes this incurable disease he called konzo. The disease requires more than a poisonous plant. Namely, poverty, severe malnourishment, conflict and a lack of infrastructure – most affected areas are far away from markets, clinics and paved roads. "If you do not find the true cause, you do not act correctly," Rosling told me last September.
To understand the connection between cassava, poverty, conflict and konzo, photographer Neil Brandvold and I traveled to a remote region in the Democratic Republic of Congo (DRC) where more than 3,500 people have been brought to their knees by konzo over the past 20 years. The town is called Kahemba, which, in the region's language, Chokwe, means the "the place of suffering."
In the DRC, cassava is served as a doughy ball called fufu that accompanies stews and greens like cassava leaves and spinach. The dish begins when women unearth thick, starchy cassava roots from the soil, and soak them in a stream for about a week. Then they dry the roots in the sun, and next beat them into flour. Add water, mix, and the fufu is ready.
Whether or not it is intentional, women make cassava safe to eat when they soak the roots. Over time, water degrades cyanide found in bitter varieties of the plant. But sometimes people here in the DRC are forced to skip the time-consuming step.
Jean-Paul Mugisho, a 26-year old man with konzo, told me why he ate cassava that had not been soaked in water when he was young. Since 1996, his area of the country, Kivu, has been mired in violence. Dozens of armed groups—many supported by surrounding nations — and the country's army have been at war. With more than 5 million dead, the ongoing conflict in the DRC is the bloodiest since World War II.
Militias take over towns and loot farms for food, he said. They unearth roots of sweet cassava, but leave the bitter ones in the ground because they taste terrible when raw. So, roots from bitter cassava "hide out" in the ground, Mugisho said. They can remain in the soil for months without falling prey to pests. Researchers suspect that has to do with the toxins that bitter varieties have evolved to contain. So families that flee their farms find their roots safely in the ground when they return. Alternatively, they take the roots on the run. But soaking them requires a stable location, a safe place they can stay at for at least a few days. And baring that, hungry people eat the roots without processing them sufficiently. Mugisho said he remembers not liking the taste, but no one knew they were dangerous.
When asked how to prevent konzo, Mugisho said, "The government needs to stop the army and warring groups."
Born in 1953, Cécile Mwandjombi (far left in the picture) told me how the land has changed since her youth. The population of Kahemba was smaller, she said, and people had space to rotate crops including cassava, cabbage, spinach and onions. That's no longer done because there are more mouths to feed than arable land. Over-farming, and perhaps an increase in droughts, has rendered the soil as cracked and dry as sand.
Mwandjombi said that prior to the country's independence, Belgium colonizers had distributed seeds and farm tools — unlike the country's current government. Now, after a dry season kills all crops except for drought-resistant bitter cassava, people have little to plant. Outbreaks of konzo predictably follow because the disease preys on the malnourished. Eating bitter cassava poses no risk to my health for example, because I eat protein, too. Amino acids from meat and beans help the body detoxify this level of poison. Kahemba's inhabitants aren't so lucky. Mwandjombi's two daughters (pictured above) have been disabled by konzo.
"In the dry seasons, my daughters and I eat just once a day," Mwandjombi said. "We eat fufu alone with nothing else."
Etienne Tshiluanjim, a skeleton-thin 28-year old, does not soak cassava roots because his wheelchair cannot traverse dirt paths leading to the river, his only source of fresh water. His mother cannot stand either. Konzo has come for his two little brothers as well. And his father has abandoned them. Neighbors donate cassava every few days. At dusk, a woman carrying a basket of starchy roots arrived. "I know cassava caused this condition," said Marie Kavumbu, Etienne's mother. "But how can we ask for this cassava to be soaked? We haven't eaten for two days and we cannot wait."
Rosling officially gave konzo its name in 1990. He connected the symptoms he'd seen in Mozambique, Tanzania and the Democratic Republic of Congo to unprocessed cassava, and chose a Congolese tribal word for the condition—konzo. It originally referred to trapped antelopes tethered at their knees. Rosling and his colleagues chose this over a name that indicted cassava. After all, he said, "It is the fifth staple crop of mankind."
Instead, Rosling placed blame on extreme poverty—a condition defined by people living on less than $1.60 per day. But that number implies cash, and people in extreme poverty, in places like Kahemba, have none. They have one or no crops in the ground. Babies are born dangerously below weight. Adults have no access to jobs. Rosling argues that people in this state are sitting ducks for emerging disease and conflict. "You need to lift people out of supreme poverty," he said. "It is misery."
Economic growth, however, is not on the horizon in the DRC. The violence feels relentless. On Valentine's Day, the United Nations reported that Congolese soldiers had killed at least 101 people in the course of five days. It was the most recent event in a wave of instability that surged after President Joseph Kabila refused to relinquish his 16-year reign in December.
In the meantime, the best hope for preventing konzo is education. One Congolese researcher who trained with Rosling, Desire Tshala, now at Oregon Health and Science University in Portland, travels for days on dirt roads to teach communities how important it is to soak cassava before consumption. And minus a cure, the best hope for those stricken with konzo is employment. A nurse who had been crippled in his youth due to tuberculosis, Theodore Nabarhimba, explained how jobs provide money and a sense of community and purpose. "We need to reinsert people into society," he said.
Gaby Ngabu Kasongo, pictured above, told me he might be dead if it weren't for his aunt, who found him a job as a tailor, and a radiant girl friend who sat leisurely by his side. "We — all the konzo people — are suffering," he said, "But though I am not well, I am comfortable."
Science journalist Amy Maxmen traveled to the DRC to write about konzo for Global Health NOW at the Johns Hopkins Bloomberg School of Public Health. Photographer Neil Brandvold's photographs were made possible with support from the Pulitzer Center on Crisis Reporting.