The people who get Podoconiosis must spend a lot of time barefoot in contact with silicate rich soil: this means that agricultural workers who cannot afford shoes are the prime sufferers. In the past this would have meant that Mossy Foot was much more widespread and In fact there is an image of a British Mossy Foot sufferer in the medieval Mappa Mundi displayed in Hereford Cathedral. The only reason that podoconiosis no longer occurs in Europe is that everyone now wears shoes. There is also a genetic factor which means that some are at greater risk than others. Today, podoconiosis affects about 10% of the population in highland tropical areas with volcanic soils and lots of rainfall.