A strange affliction in the hills of KwaZulu-Natal still evades medical science, writes Simon Pooley
DRIVE up into the remote Mseleni area in the Ubombo district of northern KwaZulu- Natal and you could be forgiven for thinking you had returned to an African Eden. The rural people live in small kraals, linked to the small sandy roads by footpaths, in the midst of thickets of forest and rolling green grasslands. The vegetation is rich and varied, despite the sandy grey soil. Nearby is the large and beautiful Lake Sibaya.
Yet somewhere within this rich paradise lurks a serpent. Doctors, missionaries and scientists have sought him out, but he disappears beyond our understanding. His work is only too apparent to the eye, however. If you go to the Mseleni Mission Hospital at the appointed time every week, you will see his victims hobbling painfully in for their therapy – the bent, the crippled, the dwarfed.
But let me do as science does, and attempt to demystify this “serpent” by giving it a name. The Mseleni area is plagued by a severe arthritic condition known as Mseleni Joint Disease (MJD). The name describes the symptoms of this disease, but glosses over its – unknown – causes.
Reading through the medical literature, one is struck by the profusion of statements like: “much further research needs to be done …” and “… needs to be investigated further”.
Summing up what was known about MJD in 1993, researchers from the Research Unit for Medical Genetics at the University of Cape Town observed that “the cause of the disorder remains enigmatic, despite more than two decades of extensive research”.
First noticed by the medical profession in the early 1970s, MJD was already known to the Nguni and Tsonga residents of the area when the first missionaries settled in Mseleni around 1912. Their name for it was isindulo or unyonga – “the disease affecting the joints”. MJD was named after the area of highest incidence of the disease, but in fact, it is also highly prevalent in neighbouring areas.
The affliction is first experienced as a pain in the knee and hip joints. As this gets worse, the joints become very stiff and difficulty is experienced in walking. Eventually, the sufferer may not be able to walk at all, or at best with the aid of a stick.
Other features of MJD include malformation of bones and a reduction in bone volume. The growth of long bones is affected, and there is a high incidence of dwarfism in the area. Besides humans, some plant forms are dwarfed, as well as fish in nearby Lake Sibaya.
In 1973, there were 2015 people living in the high incidence area, and of these, 567 were affected by MJD. The highest proportion of these were adult women, perhaps because many of the men leave the area to find work, leaving the women to grow the crops and look after their families. In 1981, 15% of females and 6% of males living in the Mseleni area were affected by MJD.
Many studies have tried to discover the source of all this misery. The local vegetation and the diet of the local people have been identified, with a view to discovering possible nutrient deficiencies or poisons. Some researchers looked into poisons, concluding that these are unlikely to be the cause of MJD.
The water has also been tested – but revealed nothing conclusive. In the light of this failure to find environmental causes for MJD, it was suggested that the disease might be genetic. But research suggested that this possibility was remote.
Is there any hope for sufferers of MJD? One area that seems promising involves the role of trace elements. Researchers note, for instance, that manganese deficiency causes very similar skeletal abnormalities in farm animals to those suffered by MJD victims. Apparently, the very sandy soils found in the Mseleni area contain very little manganese. Furthermore, maize and peanuts, the staples of the locals’ diet, are very low in manganese.
The amount of manganese that a human being absorbs after eating or drinking it is very small, and depends on the chemical balance of the body. To assess manganese levels, the balance between as many as nine mineral elements – iron, copper, manganese, zinc, phosphorus, calcium, magnesium, potassium and sodium – would have to be considered.
No one has experimented on human beings to discover the negative effects of such deficiencies. But if one could confirm such trace element deficiencies in the high incidence area of MJD, and then show that this has an observable negative impact on plant or animal growth, one might have the snake by the tail.
While many studies have suggested trace element deficiencies in the area’s sandy Fernwood soils may play an important role in causing MJD, until recently no in-depth soil analyses have been conducted to test these hypotheses. In 1996, researchers at UCT took soil and water samples from the high-incidence area. Analysis revealed that the soils were indeed deficient – in several important bone-forming elements.
And when maize, the staple food of the area, was grown in controlled conditions – both in Mseleni soil and soil from the surrounding control area, the maize grown in Mseleni soil showed multiple nutrient deficiencies. This suggests a link between the biochemistry of the disease and the soil chemistry.
But as Dr Fredlund of Mseleni Mission Hospital wearily points out, many researchers have come and gone over the years, each pursuing their pet research project, and then disappearing with their result. What is lacking is a co-ordinated approach to the problem, which may be many- faceted rather than caused by one factor. But the rural population of this remote area seems to have little chance of securing the funding necessary for such a project.
So what is being done about this disease that creates so much hardship for this already hard-pressed community? The previous health authorities did not deem a co-ordinated research project into the disease to be a priority, and this is still the case today. Instead, disability grants are paid out, and the local medical authorities spend a small fortune on hip transplants – some patients being flown as far afield as Tygerberg in the Western Cape.
What makes this situation particularly obscene is that about 20km away from the Mseleni Mission Hospital is Sodwana Bay, a holiday paradise for thousands of monied leisure-seekers over the festive season.
There must be few more striking contrasts between South Africa’s wealthy – at play in their ski-boats and scuba equipment at Sodwana – and the grinding poverty of its poor – suffering the mysterious curse of MJD at nearby Mseleni.