Konzo

Konzo (also called mantakassa) is a paralytic disease associated with several weeks of almost exclusive consumption of insufficiently processed bitter cassava. It has mainly been reported as epidemic outbreaks among women and children in remote rural populations in East and Central Africa. It was first discovered by Trolli in 1936. Paralysis (hypertonic paraparesis) is sudden, symmetrical and permanent, but does not progress. The disease onset is associated to high dietary exposure from cyanide liberated from the naturally occurring glucosides that normally are removed by processing before consumption of cassava roots. However, the full etiology remains unclear but the simultaneously low intake of sulphur aminoacids needed to detoxify cyanide have been implicated as an etiological factor. It is noteworthy that no similar type of upper motor neuron damage have been reported from cyanide exposure without simultaneous protein malnutrition and even more that no case of konzo have yet been reported from poor cassava eating populations in South America. Familial clustering is observed. Epidemics typically occur in the dry season in households living in absolute poverty that have sustained themselves for weeks or months on bitter cassava.

"Konzo" means "bound legs" in the Yaka valley, aptly descriptive of the typical hypertonic gait of those afflicted. Although no treatment has been found it has been shown that affected individuals benefit considerably from reabilitation and use of adequate walking aids.

Dr Howard Bradbury, an Australian plant chemist from the School of Botany and Zoology, at the Australian National University in Canberra, has developed a simple new method of removing cyanide from flour made from cassava that will help that can benefits millions of people who are at risk of this disease.