Nodding disease

	Africa portal
	Medicine portal

Nodding disease or nodding syndrome is a new, little-known disease which emerged in Sudan in the 1980s.^[1] It is a fatal, mentally and physically disabling disease that only affects young children typically between the ages of 5 and 15. It is currently restricted to small regions in South Sudan, Tanzania and Uganda.^[2][3]

Symptoms

The symptoms of nodding disease are very peculiar. When a child is affected by it, his/her growth appears to be completely and permanently stunted. The growth of the brain is also stunted, leading to mental retardation of the victim. The disease is named nodding disease since it causes pathological nodding. This is a seizure which begins when the victim begins to eat food, or when he/she feels cold.^[4] As soon as either of these conditions is met, the afflicted will immediately begin to nod. These seizures are brief and halt after the child stops eating or when they feel warm again. However, this symptom is very unusual as the victims don't appear to suffer from seizures when they are given an unfamiliar food, for example a candy bar. The seizures can be severe and cause the child to collapse, leading to further injury.^[5]

Diagnosis

Diagnosis is not very advanced and is based on the telltale nodding seizures of the victims. Stunted growth and mental retardation along with the seizures means there is a high probability that the disease is present. Neurological scans may also be used in attempts to diagnose symptoms of the disease in the future.

Prognosis

As the disease is not well known, little is known about the prognosis. It is thought to be a very debilitating disease physically and mentally. While a few children are said to have recovered from it, many have died from the illness.^[4] The seizures, as mentioned before, could also cause children to collapse and further injure themselves or die, for example, by falling into an open fire.

Possible causes

It is currently unknown what causes the disease. Some believe it may be due to chemicals from the use of biological and chemical weapons in the area. Another possible cause is tainted food such as spoiled plants or meats: tainted monkey-meat is one possible suspect. People in the area have also admitted to eating seeds that were provided by relief agencies and were meant for planting and were covered in toxic chemicals.

Another theory is that the disease is connected to a parasitic worm, Onchocerca volvulus, which is carried by a black fly and which causes river blindness. Most children suffering from nodding disease live close to the Yei River, and 93% of the victims carry the parasite.^[6] A link between river blindness and normal cases of epilepsy,^[7] as well as retarded growth,^[8] has been proposed previously, although the evidence for this link is inconclusive.^[9]

Prevalence

The map of Sudan districts affected by nodding disease. Red district was already affected in 2001, yellow districts are prevalent in 2011 and in green districts there are only sporadic reports^[10].

The disease is currently known to be prevalent in the Sudan region, where over 300 children are afflicted with it, and in Uganda's Kitgum district^[2]. Due to poor living conditions and poor healthcare in the regions where the disease is prevalent, little is known about the disease,^[11] although neurological scans have been performed on some sufferers.

References

1. ^ Lacey M (2003). "Nodding disease: mystery of southern Sudan". Lancet neurology 2 (12): 714. doi:10.1016/S1474-4422(03)00599-4. PMID 14649236. 
2. ^ ^{a b} UGANDA: Nodding disease or "river epilepsy"? IRIN Africa. Accessed 19 October 2010
3. ^ "Nodding disease in East Africa". CNN. http://edition.cnn.com/video/#/video/world/2011/06/05/africa.dowell.nodding.disease.cnn?hpt=hp_mid. Retrieved 6 June 2011. 
4. ^ ^{a b} 'Nodding disease' hits Sudan Andrew Harding BBC News 23 September 2003, Accessed 19 October 2007
5. ^ Bizarre Illness Terrifies Sudanese - 'Nodding Disease' Victims Suffer Seizures, Retardation, Death Emma Ross, CBS News, Jan. 28, 2004. Accessed 19 October 2007
6. ^ When Nodding Means Dying: A baffling new epidemic is sweeping Sudan. Lekshmi Santhosh The Yale Journal of Public Health Vol. 1, No. 1, 2004. Accessed 19 October 2007
7. ^ Druet-Cabanac M, Boussinesq M, Dongmo L, Farnarier G, Bouteille B, Preux PM (2004). "Review of epidemiological studies searching for a relationship between onchocerciasis and epilepsy". Neuroepidemiology 23 (3): 144–9. doi:10.1159/000075958. PMID 15084784. 
8. ^ Ovuga E, Kipp W, Mungherera M, Kasoro S (1992). "Epilepsy and retarded growth in a hyperendemic focus of onchocerciasis in rural western Uganda". East African medical journal 69 (10): 554–6. PMID 1473507. 
9. ^ Marin B, Boussinesq M, Druet-Cabanac M, Kamgno J, Bouteille B, Preux PM (2006). "Onchocerciasis-related epilepsy? Prospects at a time of uncertainty". Trends Parasitol. 22 (1): 17–20. doi:10.1016/j.pt.2005.11.006. PMID 16307906. 
10. ^ Meredith Wadman (13 July 2011). "Box: A growing threat". Nature. http://www.nature.com/news/2011/110713/full/475148a/box/1.html. Retrieved 11 July 2011. 
11. ^ Sudan A Hotbed Of Exotic Diseases - Country Has Unique Combination Of Worst Diseases In The World Emma Ross, Sudan, Feb. 3, 2004, CBS News. Accessed 19 October 2007

External links

• Mann, Jonathan; CNN, CNNstaff (2011-06-05). Nodding disease in East Africa. CNN. http://edition.cnn.com/video/#/video/world/2011/06/05/africa.dowell.nodding.disease.cnn?hpt=hp_mid. Retrieved 2011-06-07