The disease is named for the characteristic, pathological nodding seizure, which often begins with the sight of food or dropping temperatures.

[8] Sub-clinical seizures have been identified in electroencephalograms, and MRI scans have shown brain atrophy and damage to the hippocampus and glia cells.

[6][8][9] As of 2024[update] the cause of the disease was not known,[2] but a link has been found between nodding syndrome, infestation by the parasitic worm Onchocerca volvulus prevalent in all outbreak areas, and exposure to black-fly bites which transmit it.

[10] Andrea Winkler, the first author of a 2008 Tanzanian study, has said of the connection: "We could not establish any hint that Onchocerca volvulus is actually going into the brain, but what we cannot exclude is that there is an autoimmune mechanism going on.

[4] Older theories include a 2002 toxicology report that postulated a connection with tainted monkey meat, as well as the eating of agricultural seeds provided by relief agencies that were covered in toxic chemicals.

[17] As of 2024[update] no cure was known for the disease,[2] so treatment has been directed at symptoms, and has included the use of anticonvulsants used to treat epilepsy such as sodium valproate[10] and phenobarbitol.

[6] While the majority of occurrences of the disease known as "nodding syndrome" have been relatively recent, it appears that the condition was first documented in 1962 in southern Tanzania.

By 2009, it had spread across the border to Uganda's Kitgum district,[3] and the Ugandan ministry of health declared that more than 2000 children had the disease.