Even in good times, staples such as cassava and sorghum can put children at risk. Both contain chemicals that break down into cyanide, a potentially lethal compound beloved of Victorian murderers. They’re thought to protect the plants from being eaten by insects and have already been implicated in the crippling neurodegenerative disease konzo, which has been stalking the poorest and hungriest parts of East and Central Africa for generations.

Though cassava root is rich in carbohydrates, calcium and vitamin C, if it’s not properly processed – chopped up and soaked in water for several days, to reduce the cyanide content – then it will slowly poison whoever is desperate enough to eat it. The toxin destroys the neurons that carry signals from the brain to the muscles, and the end result is irreversible paralysis. Many victims end up as quadriplegics.

If nodding syndrome has a dietary cause, then uncovering it could have a significant global impact, as the disease’s strange twin has already shown; since the discovery that BMAA could be driving lytico-bodig, scientists have checked to see if it could also be involved in the development of other neurodegenerative diseases. It turns out that this might be the case – and a chemical known to protect against such damage is currently in clinical trials. It may soon provide a new way of treating patients with ALS and early-stage dementia.

“I can tell you that I am totally committed to continuing this research and I will be assembling a multi-disciplinary team that I believe will make a significant contributions,” says Pollanen. “This work can only be done as a team, and it is obvious that no one expert is going to have the total knowledge needed to solve this problem. So that is the approach that we are going to take.”

For now, the mystery of nodding syndrome drags on. Who knows, perhaps one day this obscure East African illness could provide a vital clue that unlocks treatments for many other diseases worldwide. But Pollanen is keen to point out the dangers of viewing the human tragedy in entirely clinical terms – almost as though it’s an experiment. “Particularly in my discipline, we tend to focus on the immediate consequences of internal armed conflict. We forget that these acts resonate for far longer,” he says. “And what we are seeing with nodding syndrome is part of a humanitarian crisis in the region. There’s more than a scientific reason to ensure the welfare of these children.”

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