Nodding syndrome is a bizarre new disease discovered that has been afflicting children in southern Sudan. The most common characteristic of this condition is uncontrollable nodding at the mere sight of food. This horrible condition progresses from there to severe seizures, mental retardation, and even death. The mortality of it can come by either brain damage from the nodding or starving to death because of the inability to eat.

The disease first began getting major press on Saturday, January 31, 2004. An article on focuses on a 13 year old girl named Martha Halim. She was afraid of food and eating, among other things. Her parents tried traditional medicine, like taking her to a hospital to get anti-epileptic drugs. Those did not work. Then they tried the use of a witch doctor and doing a ritual where she crawled through a termite mound while her mom and dad slit the throat of goat. Guess what? That didn't work, either.

Almost like something out of a Stephen King novel, what Martha describes experiencing just before the seizure is both baffling and frightening: "When it comes, it looks like a black cloud but in the shape of a human. That's all I know. At the end, I find myself on the floor."

Nodding syndrome has so far bewildered the experts and afflicted more than 300 children. The World Health Organization began investigating it in 2002, which was around a year after Martha's first symptom of nodding syndrome. Peter Spencer, an American neurotoxicologist working for WHO had a strange encounter with another 13 year old stricken with the disease.

He said: "I was able to demonstrate with her that she was a regular nodder with local food and by contrast she did not nod when eating a variety of American food — candy bars or whatever. It was absolutely staggering."

Desperate for some way, any way, to help Martha and others like her, Sudanese have delved into superstition, trying things like washing the bad spirits away and sacrificing sheep. Doctors working with WHO have only one working theory, that it might be related to a disease seen in Uganda called Nakalanga syndrome which indeed also features convulsions, but stunted growth, and, yes, sometimes nodding.

One theory was that the condition arose from the eating of monkeys; it was thought to perhaps be something similar to mad cow disease or ebola. But this has been ruled out. The connection might still be food, but it is unlikely, according to Spencer. He has also found no obvious environmental causes. The disease continues to baffle all who study it.

Updates 2/10/09: More theories on possible causes:

  • Chemicals from usage of biological and/or chemical weapons in the area
  • Consumption of seeds tainted with toxic chemicals that had been provided by relief agencies for the purposes of planting for crops
  • A parasitic worm called Onchocerca volvulus which is carried by the BlackFly and causes river blindness. (Most children with nodding syndrome live(d) close to the Yei River and 93% of the victims carry the parasite.) Evidence is inconclusive on a proposed link between river blindness and epilepsy and retarded growth.

Update 12/5/11: What the CDC thinks, most authoritative on the cause (thanks Tem42) apparently the they think it's a form of epilepsy but still isn't sure of the root cause.

Update 3/7/17: According to a February, 2017 report by NPR, scientists may have finally solved the mystery. It was one of the proposed ideas in the 2009 update... sort of. The parasitic worm that causes river blindness is indeed now the prime suspect, but indirectly. The cause is the immune system's response to the worm:

Tory Johnson, an assistant professor of neurology at Johns Hopkins University, seems to have finally cracked the case. She worked with Avi Nath - an author of a study about Nodding Syndrome who is chief of the section of infections of the nervous system at the National Institute of Neurological Disorders and Stroke. Johnson found that in people with the disease the immune system targeted a protein in certain muscle cells, a protein that unfortunately looks a lot like a target protein in the parasite. She looked at the brain to see if the protein was there as well. And it was... in abundance. So nodding syndrome seems to be caused from the body attacking its own muscle and brain cells in an effort to kill the parasite. Treatment efforts will include drugs to kill the parasite as soon as possible, and also drugs to temporarily suppress the immune system.