Financial Journalist

African Health August/September 1986

Hydatid disease in Turkana: drugs promise help with awkward patients. Turkana people live so intimately with their dogs and camels that the hydatid parasite is difficult to eradicate. Journalist Gerry O’Kane reports.

KENYA’S most north-western province, Turkana, suffers more than and poverty and prickly thorn bushes. More people are affected by the parasitic Hydatid disease than any other place in the world. Caused by tapeworm in animals, eggs pass through the animals’ excreta and if man should happen to take the eggs orally, cysts can develop.

1983 saw the beginning of an effort to tackle the problem and the African Medical and Research Foundation (AMREF) set up Africa’s first hydatid control programme. Although only a pilot scheme, Eberhard Zeyhle, a West German parasitologist working for AMREF points cut “We cover the north-west area of Turkana, some 9,000 km sq. with about 15 000 Turkana people - not an easy task.” Officially AMREF say that the programme is to provide “an integrated multidisciplinary approach which will examine the epidemiological factors which create the problem and simultaneously develop new strategies to provide the economical and effective means of controlling it.”

What this means is that they have set themselves a task not only to eradicate its causes but also to pioneer the use of new drugs to cure it. Three years later their progress is still agonisingly slow - operations that physically remove the cyst remain the only cure for hydatid sufferers - but solutions are being put into effect.

“I’m convinced that we’ll be successful” said Zehle “but it is so frustrating. Sometimes when you think you have a good line, the parasite hits back and leaves you more confused . . .” Not only is the project faced with covering a large area of hostile terrain but also a population that is suspicious of modern medicine and can be incredibly uncooperative. On the research front, there is no routine method for distinpuishing the hydatid organism (Echinococcus) from some other species of organisms.

The solution that the programme is trying to produce involves devising new techniques of parasitic analysis, developing new methods of treatment, educating the Turkana to new standards of health and dramatic changes in their social lifestyles. Add to that the pressures of only another three years’ funding and their project seems doomed to failure. But AMREF has made steps forward. It was in 1958 that the Medical Officer in Kitale first noticed the unusually high incidence of hydatidosis in the Turkana. Although it was not uncommon in animals in the rest of Kenya, indeed cases of it in farm animals are still found in Britain, it was rarely seen in man. Between 1960 and 1980 AMREF have been directly involved in treating over 1,500 cases. For such a large region populated by a nomadic tribe averse to modern methods, the figures probably do not reflect the true incidence of the disease. Until then Cyprus was believed to have the highest rate for hydatid. Zeyhle admitted that one of the reasons he joined AMREF’s research project was the enormous number of cases, “We saw 14 cases in the first week here, mostly children. I couldn’t see that many cases in Germany in a year.”

Recent surveys are more detailed, now estimating that as many as 200 per 100,000 get hydatidosis, with females in the child-bearing age group having over three times the infection rate of men. Earlier research from countries like Iceland and Egypt pointed to animals as being an essential link in the chain of transmission to man, particularly domestic animals.

In Turkana it was discovered that 19 out of every 27 dogs were infected with the Echinococcus worms, a higher rate than any wild or domestic animal tested. The Echinococc s organism is suitable for developing mutant strains and this is one explanation of Turkana’s high rate of infection, also making it more difficult to find a solution. While the horse strain found in Britain rarelv affects man, the strain in Turkana is obviously highly infective. Man is not just an intermediate host but a victim.

The unhygienic lifestyle of the people and their harsh living conditions also make infection more likely. A tapeworms eggs are passed through the infected animal’s excreta. Man then gets the disease when he swallows the parasite. The eggs hatch in the part of the gut joining the stomach to the small intestines and on becoming larvae enter the blood by penetrating the intestinal walls. Travelling around the blood stream, the larvae eventually lodge themselves in various parts of the body and develop into a cyst.

In Turkana the dog is the major carrier. AMREF see several ways in which they originally get the disease. Although fewer other farm animals compared to the rest of Kenya are infected, camels have been found to be heavily diseased. Often their remains are fed to dogs and their contaminated meat can pass the organism on.

Dogs also have the opportunity of feeding off humans who may have been suffering from hydatid cysts. It’s not unusual for the ‘l’urkana to leave the dead or dying where they fall, especially if the tribe is on the move. Even for buried dead the graves are normally shallow, consequently dogs often feed on the corpses.

The dog plays an important social role in the Turkana’s lifestyle and its intimacy with the people explains how high transmission rates occur. Dogs are used as “nurses” for infants and women usually have one during the child-rearing period. This would help explain why women are three times more likely to get the disease. Specially trained, the dogs lick up children’s vomit and faeces in the manyatta (hut) and also lick the children’s face and anus when they soil themselves. This gives ample opportunity for the people living in the manyatta to become, infected by the Echinococcus eggs entangled in the beasts’ muzzle and fur.

But there are numerous other ways in which infection can be spread. The tribe often use faeces as an ingredient in the preparation of dressings on cuts or as part of a lubricant mixture used on their heavy necklaces. Producing their locally dried milk also creates a risk since it is laid on skins and left in the sun to dry. Not only is the milk open to interference from dogs as it dries, but the skins on which it is drying are often the dogs’ sleeping mats.

Although there is some doubt as to how resistant the Echinococcus eggs are to heat, involved in the other processes, there is no doubt that the eggs can be spread through water holes. Not only do the people and animals drink from them but the animals also wash and defecate in them. The water is often stagnant and Zeyhle suggests that over 700 eggs per litre can survive.

“Essentially the disease is caused by unhygenic conditions and it’s only through the long and arduous task of education that we can combat the problem” he said. Quoting Dr. MacPherson, head of the AMREF project, Zeyhle noted “The solution to the disease lies with the Turkana. themselves.”

Although the people are aware of hydatid, (they call it espeses) educating them in methods to control it has meant setting up education groups led by elders, chiefs and in many cases school children. But this type of change will be slow. “The Turkana are a tough people and frankly, don’t cooperate. We are far away from education,” sighed Zeyhle.

Nevertheless progress has been made and AMRFF are following the successful dog eradication programme used in Cyprus. Acceptance of the programme has been gained and the killing of unwanted puppies is encouraged, as is the sterilisation of bitches. Zeyhle estimated that 60% to 70% of the dog population would have to be killed. Following the eradication scheme AMREF intend to register the dogs and treat them with Praziquantel. While a single dose will kill the dogs’ eggs and tapeworm, the animal can be reinfected -Within six hours but it takes at least 42 days for the worms to produce more eggs. AMREF plan successive doses every 42 days.

This is only part of the plan to combat the problem. Keeping dogs away from sources of infection is also planned, for example preventing the dogs access to offal by fencing off abbatoirs and cemetery areas. Naturally this means the Turkana must bury their dead in particular areas and kill their livestock in a controlled way. Hanging meat out of animals’ reach is another option. “We also want to get the Turkana to keep the dogs out of their homes but it means avoiding the close contact with the animal that they are used to,” said Zeyhle. Again it returns to the frustrating area of education.

Unfortunately treating victims of hydatidosis hasn’t made many strides forward, still depending upon surgery. it has, however, highlighted yet more anomalies of the organism. If during the operation the cyst should burst, it releases more organisms which begin to grow again. “I suppose the postoperative recurrence rate is about 20%. Usually you can’t operate again,” said Zeyhle.

What is interesting about any cyst bursting during an operation is that the shock of the alien organisms flooding the body would, in 9 out of 10 cases, kill the patient. “They should die from the shock to the system but for some reason the Turkana survive. We think it might have something to do with their normally malnourished state - their immune systems simply haven’t got the energy to respond and so they avoid shock. But we don’t know for sure,” revealed Zeyhle. On the chemical front AMREF are working with the Kenya Medical Research Institute (KEMRI) to find a drug that can cure patients. At present the future looks not too dark with Albendazole signalling that this might just he the breakthrough the project has been looking for.

Hydatid disease in Turkana, Kenya, parasites