The medical importance of shoes
Podoconiosis is one of a number of neglected diseases causing pain, disability and disfigurement that are responsible for maintaining the world’s poorest and most vulnerable communities in a cycle of poverty and disease. Recognising the importance of these neglected conditions on global health the Trust has made significant research commitments in this area over many decades. Here Marta Tufet, Wellcome Trust International Activities Adviser, raises awareness of this disease, and highlights some research studies that the Trust currently supports, that may provide solutions for its control.
Some years ago my friend Zsofia asked me to accompany her to buy a pair of “the ultimate hipster shoes”. So off we went to fight the masses on Oxford street. When Zsofia presented me with the shoe, I was surprised to learn I had actually been a hipster all my childhood. Basically this shoe was what as a Catalan I would call an “espardenya” (or as a South American an “alpargata”) – traditional footwear from the Pyrenees dating back to the 14th century, comprising canvas fabric and a sole made of rope or more recently rubber. These only cost a couple of euros in Spain, so why was Zsofia prepared to pay over twenty pounds? She educated me, “well it’s kind of a rip off, but it’s for a good cause. For every pair of shoes I buy, TOMS, the company gives a pair to a kid in a developing country”.
Shoes. Really? Would it not be better to advocate real life-saving solutions such as bednets, vaccines or even food? It’s true that shoes protect us from some injuries and they may even give us a better grip on car pedals, but millions of people walk barefoot, so why should we impose our social norms on other communities?
Working on Global Health at the Wellcome Trust I have now come to learn that, for certain communities in the tropics, wearing shoes can indeed be life saving. They provide protection from a range of conditions such as parasitic worms, tetanus, jiggers, snakebite, Madura foot and, importantly, from an unfamiliar and neglected disease called podoconiosis (or “podo” for those of us who can’t pronounce it).
Not to be confused with lymphatic filariasis (a form of elephantiasis caused by worms), podo is not an infectious disease. It is not caused by bacteria or parasites, but by an unusual reaction to irritant minerals found in red clay soils of volcanic origin, such as those found in the highlands of Ethiopia. Little is understood about the mechanisms causing podo but it seems that minerals enter the lymphatic system through the exposed feet of many subsistence farmers and trigger an abnormal inflammatory response that creates severe foot swelling leading to elephantiasis. This painful and disfiguring ailment prevents around four million affected people in highland areas of Africa, Central America and north-west India, from walking, working and ultimately feeding their families and themselves. Feet are enlarged and disfigured, they ooze and smell, and although it is not contagious, podo often runs in families, implicating that there is a hereditary component. This, coupled to a lack of understanding in the rural communities, has led to huge stigma associated with podo and most afflicted individuals are shunned from their communities.
Podo is completely preventable by wearing shoes, but shoe-wearing is not solely an economical matter, there are many social, cultural and behavioural barriers to this. Treatment of those already affected may also be possible but more research is needed to better understand the disease and inform potential solutions. Prof. Gail Davey, a medical epidemiologist at Brighton and Sussex Medical School and Executive Director of Footwork has dedicated the past decade of her life to combating podo. Through Footwork she co-ordinates international research teams that investigate the causes and pathogenesis of the disease, its distribution, social and economic implications, as well as clinical and community management and behavioural interventions to improve prevention.
This coordinated research effort is paying off. Last year, Wellcome Trust-funded researcher Prof. Melanie Newport, also at Sussex, led a genome study that identified genes in certain individuals that increased the risk of developing podo. The region in which these genes were found (HLA class II) plays an important role in the control of our immune system, confirming that there is indeed an immunological basis to the disease. This discovery suggests that drugs targeting immune responses could be useful.
Gail’s own research has shown that simple and cheap lymphoedema management, such as washing feet with water and antiseptic, applying emollient, bandaging, and wearing of socks and shoes can reduce the swelling and improve the appearance and quality of life of patients. Gail says that “following treatment even for a couple of months, our patients become able to attend social gatherings, sometimes after more than a decade without human contact beyond the family”.
Funded by the Joint DFID/MRC/Wellcome Trust Global Health Trials Initiative, Gail and her team in Ethiopia will be recruiting patients this year for a trial to formally test whether this type of intervention can successfully and cost-effectively improve clinical outcomes for affected patients.
In parallel, an Ethiopian researcher and recipient of a Wellcome Trust Training Research Fellowship, Kebede Deribe, is mapping the distribution of both podo and lymphatic filariasis through the use of smartphones with the hope that these data will be able to inform future interventions.
Unlike many other neglected diseases podo, is completely preventable and potentially treatable, but the current lack of awareness of this disease means that there are no aid programmes focused on it and most governments have no programmes to assist the afflicted communities. Gail, Melanie, Kebede and Blake Mycoskie (founder of TOMS) have a vision to eliminate podo within their lifetimes, but they know this will require more than giving shoes. They are working towards an integrated approach combining prevention, treatment and education to combat podo, and with our engagement in higher income societies, elimination may indeed be within our reach.