Popular technology beats schisto / by Paul Taylor

Popular technology beats schisto 1J he traditional pit latrine smells, breeds flies and prob-ably is the source of more disease in the community than it controls. Most people dislike it and will only use it in an emergen- cy, or in areas of high population density where there is no natural vegetation for privacy. With de- forestation a common problem, the nearest bush for cover is often on the bank of a stream-but washing in the stream after excret- ing increases the risk of schis- tosomiasis. This disease can only be transmitted when first someone contaminates the water with ex- creta, and secondly other people come in contact with the same wa- ter. Over 60 per cent of school- children in some parts of Zim- babwe are infected, making schisto a very big health problem. Better health and better social status are inextricably linked. This is why Zimbabwe has given very high priority to improving water 28 by Paul Taylor supplies and sanitation, expected to have a wide-ranging impact on health and social development. The national policy for schistosomiasis control, as for many other diseases, envisages first improving water supply and sanitation in schis- tosomiasis-endemic areas. This ap- proach will reduce the risk of long- term dependence on the frequent use of drugs, undesirable both fi- nancially and because there could be a catastrophic reversal should the drugs become scarce. Long- term schistosomiasis control is therefore based primarily on im- provements in basic living con- ditions and changes in human behaviour. The Ministry of Health's Health for all action plan estimates that This bucket pump is one of several simple models designed for use and maintenance by the village. Photo WHO/L. Taylor only 15 per cent of the rural popu- lation today have adequate excreta disposal facilities and safe water. The estimated shortfall is some 750,000 latrines and 75,000 pro- tected water-points. An optimum programme calls for the construc- tion of 70,000 latrines and 7,000 water-points each year for 20 years. The Blair latrine, developed at the Blair Research Laboratory, Harare, has a vent pipe fitted with a fly-screen of fibreglass or stainless steel ; a variety of versions are now being built in Zimbabwe. The most important aspect of the sanitation and water programme has been sensitising the community and mod- ifying technology, particularly the latrine, to suit local · customs. Whenever the basic latrine is to be introduced into a new area or coun- try, it should be evaluated with that community, even if it takes several years. The advantage of community responsibility for the construction of the latrines is that people's pre- ferences became immediately appa- rent : they will not build what they do not want. In contrast to the traditional pit latrine, the Blair latrine generally does not smell (if correctly con- structed), actively assists in control- ling flies in the community, and is often used as a bathroom. These features explain the overwhelming support for it in Zimbabwe. A family building a latrine is given cement and a fly-screen to symbolise the importance the gov- ernment attaches to latrines in the family setting. In return, the family digs the pit, collects the sand and gravel, makes the bricks and builds the toilet. The family's con- tribution-whether in cash to pay a builder or in labour to do the job itself- is considered by far the big- gest, and it is the success of this community self-help which has W ORLD HEALTH, July 1987 made the sanitation and water pro- gramme so dynamic. Communal latrines are not recommended, ex- cept at schools, shopping centres or bus stops, for example, because they are too difficult to maintain. People prefer to have their own latrines near to home. The fact that very young children go with their mothers to water is the most likely reason for the high prevalence of schistosomiasis in children under six. It is important to provide not only good drinking wa- ter at a water-point, but facilities for all water-contact activities. In particular, this means washing- slabs, so that women can avoid the most common types of water-con- tact activity by themselves and their children. In one study in Zimbabwe, simple washing-slabs and washing-lines reduced the amount of water-contact at the nearby rivers by 80 per cent. The water programme is much more difficult than the sanitation programme because water-points are entirely communal and the technology is much more complex. Water technologies for use and maintenance in villages include the hand-operated drilling rig, a simple bucket pump, two types of simple hand pump and an improved type of deep well pump. As with the sanitation programme, the em- phasis is on community involve- ment and responsibility for mainte- nance. Every effort is made to see that the most reliable equipment is used, but it must be accepted that there will be breakdowns, so priori- ty technologies are those which can be maintained in the village. The water-point must be repairable with the minimum of delay. It is better therefore to have a pump which is made, and can be maintained, with parts from within the country. Although most large water sup- ply schemes, including deep bore- holes, tend to be set up with minimum community involvement, changes are coming rapidly. Now- adays, the community is often in- volved in digging pipelines and pro- tecting completed boreholes. This last is particularly important: the boreholes of the past had muddy and thoroughly unpleasant sur- rounds, whereas the newer ones have an apron and soakaway as well as a washing-slab built by the community. The community is also involved in the simple maintenance WORLD HEALTH , July 1987 Zimbabwe's favourite, the Blair latrine. It doesn't smell, keeps down flies and can even be used as a bathroom. Photo W HO/L. Taylor of the borehole and pump, such as greasing and tightening of bolts. The community's main contribu- tion has been installing and main- taining simple hand pumps. This became possible when a local com- pany developed the "Yonder Rig" -a robust yet simple-to-oper- ate drilling rig that can be used by local people with very little super- vision. Local people know the best sites for underground water and can be largely instrumental in deciding the location of their water-point. In contrast to human well-diggers, the rig's auger can get to below eight metres in less than a day, and may go down to over sixteen metres. If the drilling is unsuccessful, the rig can be moved to another site with only minor inconvenience. The disadvantage is that the auger can only cut through soil or decom- posed rock, not hard rock or stony substrates. The community gather, often in large numbers, to help in the drill- ing operation. The atmosphere is more that of a social occasion than of a labour gang-perhaps this is what a "working party" really means! Even if the auger is un- successful, progress can still be made by protecting existing wells, again best done with community assistance. The programme attracts enorm- ous community support and en- thusiasm largely due to the efforts of the village health workers and the community involvement and participation method. Water is a felt need, and the community have gained access to the technology that enables them to satisfy their own demands. Although the schistosome's life- cycle can be attacked at several points, with the arrival of new, safe drugs many national control pro- grammes have chosen to rely heav- ily on chemotherapy. This carries the risk of only short-term gains, as mentioned. If however, chemo- therapy is linked with improve- ments in water and sanitation, then the foundation exists not only for a permanent reduction in the schistosomiasis problem but also for a much better overall health and socioeconomic status within the community. • 29