Salient. Victoria University Students' Newspaper. Volume 39, Number 25. October 4, 1976
An Inexpensive Cure — Controlling Disease -
An Inexpensive Cure
Controlling Disease -
The Chinese Way
Schistosomiasis, known in Africa as Bilharzia and in China as mail fever, affects 200 million people in over 70 nations. It is a less spectacular, and therefore a lest well-known disease than malaria or cholera, but in its own quieter way it is probably the most serious off all the major diseases of the Third World. As a debilitating disease, causing general ill health and listlessness its effect on economic development is enormous. As a progressive disease, causing the eventual disruption of the liver and spleen; it can kill.
The disease is caused by worms which live in water and which can penetrate the human body on contact. The worms then breed inside the liver and produce spined eggs which pass out of the body again in a the faeces and urine. The worms life-span can be up to 30 years and it can produce about 300 spined eggs a day. In areas where water supply and sanitation are inadequate, the faeces and urine containing the eggs, usually end up in the ponds, lakes and streams which are often the main source of water for washing, cooking, and drinking. There, the eggs hatch into larvae which enter small fresh-water snails and change into fork-tailed infective larvae which can penetrate the human skin and re-enter the body.
Dr Letitia Obeng, former Director of Ghana's Institute of Acquatic Biology and now a Senior Executive with the United Nations Environment Programme in Nairobi, has made a special study of the disease as part of UNEP's programme to find environmental ways of controlling it. She has recently returned from the People's Republic of China which, until recently, was one of the nations hardest hit by schitosomiasis. She was interviewed by the New Internationalist magazine.
Why was China chosen for the study tour of Schistosomiasis?
Schistosomiasis, or "Snail Fever" as the Chinese call it, has affected vast numbers of people in the countryside of China for over 2,000 years. In 1949, an estimated 10½ million perople were infected and 100 million more were at risk.
Today, two thirds of the previously infected people are cured and more than two thirds of the areas affected by schistosomiasis are now free of the disease. In a commune in Kiangsi Province, for example, the actual incidence of the disease has dropped from 50% of the population in 1949 to 0.3% in 1968. In China today, schistosomiasis is no longer a major public health problem.
This is what makes the Chinese experience so potentially valuable to the world-wide effort against schistosomiasis. It was one of the hardest-hit countries and yet they have succeeded in bringing it under control. From my particular point of view, there is special value in the fact that the disease has been defeated largely by environmental action to break the life-cycle of the snail and to prevent the parasite coming into contact with the human body. This is UNEP's special interest. I joined the study tour to China to find out how the Chinese experience could provide guidance for other countries in dealing with this major health and development problem.
What kind of environmental action has been taken?
The Chinese have based their campaign on sound ecological knowledge and management. Knowing that the disease was spread by the disposal of human body wastes in water systems, they have put the major emphasis in providing clean water and safe sanitation and sewage disposal. Knowing that the snail is amphibious and cannot survive for many months in either soil or water alone they have 'drowned' and 'buried' millions of snails. Knowing that the snail thrives in slow-running waters they have increased the flow of streams and canals. Knowing that the preferred habitat of the snail is often around the roots of weeds, they have cleared vast amounts of weeds from the waterways. Knowing that the snail lives in the top 6 centimetres of soil when the weather is hot, they have concentrated their offensive in June and August. Knowing that over a third of the snail population lives on muddy banks within one third of a metre above or below the waterline, they have scraped the banks clean of snails and re-dug the side of waterways to make them steeper.
How has China been able to implement this programme on such a vast scale?
By a commitment to the campaign at the very top and by mass involvement in mass dedication to the task of ridding the country of the disease.
Perhaps the most remarkable thing of all is that century old practices have been changed very very quickly. Faeces has been regarded as valuable manure for centuries in China and buckets of untreated faeces have been traditionally used on paddy fields. It is a good method of fertilizing the land, but it is also a good method of inoculating the fields with the eggs of the schistosomiasis worm. So and important part of the campaign has been the change in the system of faeces disposal. The peasants have developed new methods consisting basically of a three-chamhered pit latrine which is clean, convenient, odourless and in which the new sewage ferments into a safe liquid fertilizer. By adding straw, methane
Disposal of raw faeces and rinsing of buckets in canals and rivers is now forbidden. To make sure that the disease does not launch a counter-attack, the communes organise regular surveillance for infected people and snails. In the East Wind Production Brigade near Wushi, for example, 300 men search the area for snails twice a year for three or four days.
Side by side with the new sanitation methods, the Chinese have worked hard to supply clean water to homes in rural areas. Wells have been sunk to serve small groups of homes and in one kitchen which I visited there was even a 'kitchen well' just next to the cooking stove. Bottles of soldium hypochloride are hung inside the wells to sterilise the water.
This achievement is a tribute to the Chinese information, and education machinery. They have used slides, they have used films, they have used radio broadcasts, they have used pictures, they have acted plays, they have erected huge hoarding boards, they have piped messages and music by loudspeakers to the fields, they have disected infected rabbits, they have used demonstrations - all this at the village level. So everybody really understood and everybody was really involved. Even young children were picking snails out of river banks with chop sticks and old people were taking tea to the snail control workers in the fields. Almost everyone, even though many are still illiterate, understands the causes of snail fever and knows how the pit latrine system works and why it is safe.