We are studying Ethiopian soils to investigate the role of fine clay minerals in podoconiosis.
Podoconiosis is an unusual form of elephantiasis that causes abnormal swelling of the lower legs. The disease is a considerable public health problem and economic burden in countries like Ethiopia, where it affects up to one million people.
Biological agents are responsible for the most common form of elephantiasis. But research suggests that mineral particles in soils formed from ancient volcanic eruptions could trigger podoconiosis.
We are part of a collaborative project to identify specific podoconiosis-causing triggers within soils and geological deposits. The team includes scientists from the Museum and Brighton and Sussex Medical School, as well as researchers in Ethiopia.
The research is contributing to our understanding and awareness of podoconiosis. Our ultimate aim is to eradicate the disease.
In the 1970s, British leprologist Dr Ernest Price established the link between soils of volcanic origin and a form of elephantiasis. Dr Price described the disease and named it podoconiosis, from the Greek words for foot and dust.
Podoconiosis has been identified in many regions around the world, including Africa, Central America and Asia. It is particularly well documented in Ethiopia, where misconceptions about the cause of the disease have led to social stigmatisation.
The World Health Organization classified podoconiosis as a neglected tropical disease in 2011. Since then, government-backed programmes to address prevention and treatment have been launched.
Research suggests that years of walking barefoot on irritant soils results in abnormal swelling and the growth of lesions on the legs and feet. However, not everyone who lives and works on irritant soils without shoes becomes affected, and our research has identified a strong hereditary susceptibility to podoconiosis.
Jennifer S Le Blond, Peter J Baxter, Dhimiter Bello, Jennifer Raftis, Yordanos B Mollaf, Javier Cuadros, Gail Davey (2017) Haemolytic activity of soil from areas of varying podoconiosis endemicity in Ethiopia. PLoS ONE, 12, e0177219.
Jennifer S. Le Blond, Javier Cuadros, Yordanos B. Molla, Tadesse Berhanu, Mohammed Umer, Peter J. Baxter, Gail Davey (2015) Weathering of the Ethiopian volcanic province: A new weathering index to characterize and compare soils. American Mineralogist 100, 2518-2532.