This paper is concerned with the role of the economist in the planning and appraisal of tsetse and trypanosomiasis control (TTC) operations and related research. The importance of economic analysis in decision-making is widely acknowledged, and a number of economic studies have now been completed in various parts of Africa. However, many African countries have given insufficient priority to developing their own institutional capability for veterinary and livestock economic analysis. This paper argues that more attention needs to be paid to developing such capability with in the continent, either by establishing and strengthening national veterinary economics units and/or by setting up regional units to provide economics support to national agencies.
Zimbabwe provides an example of a country which has actively explored the role of the economist in tsetse and trypanosomiasis control. Various aspects of Zimbabwe's experience and the lessons it provides for other countries are described in this paper.
1 Tsetse and Trypanosomiasis Control Branch
Department of Veterinary Services
P.O. Box 8283
1. The Origins of Concern about the Economic Justification for Tsetse and Trypanosomiasis Control
Although trypanosomiasis control has been carried out in many parts of Africa for almost a century, financial and economic analysis of this activity is a comparatively recent phenomenon. Several reasons can be suggested:
Like many other public services, trypanosomiasis control does not generate direct revenue to the Government department which carries out the task, so there is no obvious financial profit to be monitored and evaluated. Benefits all accrue privately to farmers.
Prior to the advent of chemical methods for tsetse control, most campaigns were concerned with managing almost crisis situations of human or animal trypanosomiasis outbreaks, where there was little doubt about the justification of control.
There was little choice about how to approach the disease problem: if something appeared technically effective, it was worth doing.
The effects of trypanosomiasis on livestock productivity are complex and difficult to quantify.
Accurate background information on people, livestock and land use in tsetse-affected areas was often very limited outside commercial ranching areas.
With the advent of comparatively cheap insecticidal methods of tsetse control in the late 1950's and early 1960's, a new era had arrived. Across Africa, well-organised trypanosomiasis control organisations showed that it was possible to move from defence to attack in the battle against tsetse and trypanosomiasis. Ambitious campaigns were undertaken to clear very substantial areas of land previously infested with the fly, for example in Northern Nigeria (from 1955 onwards), in East Africa and in Zimbabwe (from 1961 onwards). For a brief period chemical control gave prospect of continent-wide eradication of Africa's bane, as Nash (1969) had described the tsetse fly, culminating in the FAO/WHO Programme of Action (FAO, 1974) - a forty-year plan to control the fly over some five million sq. Km of the continent.
It is around this period that interest in economic aspects of trypanosomiasis began to appear more frequently in the literature (Nash, 1960; Jordan, 1961; Wilson et al., 1963). Some papers assessed costs of operations (e.g. Whiteside, 1962), while others began to examine the economic impact of trypanosomiasis in the context of justifying control operations. At first this discussion was qualitative (e.g. Nash, 1960) and then in simple quantitative terms. For example, Wilson et al. (1963) attempted a gross statistical evaluation of the economic importance of trypanomosiasis in Africa as a whole, based upon a crude calculation of area infested, potential livestock carrying capacity and potential demand for meat for domestic consumption in African countries.
Goodwin (1973) estimated that trypanosomiasis in cattle cost at that time about US$ 5 billion per year. At FAO, Finelle (1974) attempted to review the economic problems raised by African animal trypanosomiasis and had little to add to the previous appraisals, concluding that “data are so limited that it is almost impossible at present to draw up even an approximate report”. FAO commissioned a number of short economic studies of projects being implemented in Botswana (Negrin and Mac Lennan, 1977) Nigeria (Jordan et al., 1978) and in 1977 organised a special conference in Rome to consider economic aspects of tsetse and trypanosomiasis control (FAO, 1977). As noted by Shaw (1986), the costs of control operations were usually well-documented in these reports, but benefits were commonly discussed rather than quantified.
Perhaps the period of almost zealous euphoria that accompanied the introduction of cheap, effective chemical methods of tsetse control was the point at which people began to seriously question whether tsetse control was after all such a good thing. The need began to be felt for more detailed justification for such expenditure than had hitherto been produced. Other factors undoubtedly contributed to the increased attention to economic analysis of trypanosomiasis control in this period. From the mid-1950's onwards African countries gained independence from previous colonial rule, leading to an era in which TTC operations were increasingly organised as aid projects funded by Western donor nations and multilateral organisations such as FAO, for whom detailed economic justification was to become prerequisite.
2. Objectives in Economic Analysis of TTC Operations
Standard methodologies for economic appraisal of investment projects and public sector expenditure in developing countries are well documented in texts such as those by Mishan (1971), ODA (1971), Gittinger (1972), Little and Mirrlees (1974) and others. Chapters on economics are even appearing in reference texts on trypanosomiasis (e.g.Jordan, 1986, Chapter 11). The two main objectives in economic analysis of TTC operations have been:
(a) Benefit-cost Analysis
One objective is to examine the justification of spending a given amount of money for a specified activity, by identifying, quantifying, valuing and comparing the benefits and the costs associated with that activity. Such benefits and costs are to include those arising outside the direct boundaries of the project or activity itself.
Prices for inputs and outputs are adjusted to reflect true value to the economy rather than prevailing domestic market prices, where these are distorted for example by government subsidy, tax or other form of control.
As costs and benefits are likely to raise for many years after the investment, future cash flows are projected. These are translated into equivalent current values by a discounting process in order to arrive at the net present value (NPV) of the investment, or a benefit-cost ratio, or the internal rate of return which is a measure of the interest rate earned by investment in the project. These parameters can be used as criteria for deciding upon the allocation of resources.
(b) Comparative cost analysis
There are usually several technical options available for dealing with a given tsetse and trypanosomiasis situation. Economic analysis provides a framework for deciding which is the most cost-effective way to proceed, through comparative cost analysis. By identifying those assumptions which are crucial to making one method financially superior to another, it is then possible to identify critical points when one technique becomes superior to another. Some techniques are more capital intensive and require foreign exchange for import of chemicals, equipment and expertise. Other techniques may use a higher proportion of locally available materials and labour. By using economic (so-called shadow) prices, cost-competitiveness can be assessed rigourously and consistently to reflect for example national shortage of foreign exchange and government policies to promote employment.
3. Previous Economic Studies
The first economic evaluation of TTC was carried out in Uganda in the late 1960's (Jahnke, 1974 and 1976). The main thrusts of this study were:
cost-comparision of game elimination, bush clearance and ground spraying as methods for control of savanna species of tsetse; and
economic benefit-cost analysis of beef production (commercial versus pastoralist) under scenarious with and without tsetse control, in the latter case with prophylaxis and/or using trypanotolerant cattle. Wildlife utilisation was also evaluated as an alternative land use.
Camus (1981a) carried out a thorough and detailed study in the Ivory Cost to establish the effect of trypanosomiasis on the productivity of four types of cattle and extended this work (Camus, 1981b) to an assessment of the economic impact of the disease. However, he did not assess the economics of intervention in any detail.
In Nigeria and Mali, Shaw (1986; Putt et al., 1980) took Jahnke's work several stages further, her main contribution possibly being the development and application of computer models for improved analysis of projected benefits from TTC, particularly in relation to herd growth and productivity with and without veterinary intervention, and different scenarios of human population density. Shaw also put much effort into identification and accurate assessment of all the direct and indirect effects of trypanosomiasis and its control. Her comparative cost analysis was mainly concerned with tsetse control by insecticidal ground spraying versus drug treatment of cattle.
Habtemarian et al. (1983a, b) developed a computer model which they used for benefit-cost analysis of trypanosomiasis control in Ethiopia, comparing insecticidal ground spraying with game reduction.
Brandl (1985, 1988a and 1988b) has reported on economic studies of trypanosomiasis control in Ivory Coast and Burkina Faso. He compared the cost-effectiveness of the sterile insect technique with aerial application of residual insecticides and the use of insecticideimpregnated traps, mainly in the context of control of riverine tsetse species. He carried out economic benefit-cost analysis of tsetse control in areas of pastoralist cattle production in which projected livestock revenues were confined to herd growth, milk, slaughter offtake and live sales.
The large-scale ODA-funded tsetse eradication programme carried out in Somalia in the 1980's has included attention to economic and land use issues, which revolved around the effects of pastoralist use of riverine grazing areas along tsetse-infested major rivers (Putt, 1983; Hendy, 1986 and 1987; Hendy and Daniels, 1987).
In addition to these major studies, more limited economic studies have also been carried out in Botswana (Putt, 1985), Kenya (Wilson et al., 1981 and 1986), Tanzania (Matteucci, 1971), Zambia (Leslie, 1987; Putt et al., 1988) and Zimbabwe (Falkenhorst, 1983). Other reports and papers relevant to economic assessment of trypanosomiasis control include those by Aldhelm (1980), Finelle (1987), Griffin and Allenby (1979), Shaw (1989) and Toure (1981).
4. The Present Study in Zimbabwe
The Tsetse and Trypanosomiasis Control Branch in Zimbabwe is now approaching the end of a four year ODA-funded project to examine social and economic aspects of the Government's tsetse and trypanosomiasis control operations. As with previous studies, the central concerns were to examine the economic justification for tsetse control and to carry out detailed cost studies of the alternative methods of control.
Comparative cost analysis of alternative methods of control has been extended (Allsopp and Barrett, 1988; Barrett, 1989a; Barrett, in preparation) to include:
the use of odour-baited insecticide-treated screens (targets);
direct application of synthetic pyrethroid insecticides to cattle;
aerial application of non-residual insecticides;
ground spraying with DDT versus synthetic pyrethroids; and
drug management of trypanosomiasis.
Direct application of synthetic pyrethroids to cattle appears to be the cheapest way of controlling tsetse flies, where cattle are present, well-distributed, and veterinary infrastructure is adequate. The use of targets for tsetse eradiation appears cost-competitive with DDT ground spraying for control of Glossina morsitans, and significantly cheaper in the case of G. pallidipes, with the added advantage that targets have much less environmental impact than other forms of chemical control. Aerial application of non-residual insecticides is the most expensive of the techniques recently used on a large scale in Zimbabwe. Apart from the advantage of being able to cover large areas in a small time, this technique does not require the very large and well organised force of vehicles and trained manpower which is involved in ground spraying operations.
Cost analysis has impinged upon the planning of research projects as well as control operations in Zimbabwe, particularly in relation to targets. Through analysis of the contribution to total cost arising from each component of the technique, including labour and vehicles as well as chemicals and materials, it has been possible to identify opportunities for modifying the technique to improve cost-effectiveness. For example, possible improvements included:
increasing the total amount of odour per target in order to minimise the number of targets per sq. Km that need to be deployed (mainly a trade-off between chemical cost and materials cost); and
increasing the amount of insecticide used per target in order to reduce the number of visits required per year for servicing (mainly a trade-off between chemical cost and manpower/vehicle costs).
Assessing the Economic Justification for Trypanosomiasis Control
Attention has focused on small-holder agropastoral farming systems (the so-called communal farming system in Zimbabwe), where the economic outputs of livestock production are firstly draught power and secondly milk for domestic consumption. In most previous studies the emphasis has been on beef production or pastoral production systems.
The economic appraisal of veterinary interventions in small-holder mixed farming systems is difficult because most of the output from livestock production is not marketed but consumed within the household. Also, provision of draught power is an intermediate output ultimately represented by increased crop production by the rural household. Attention has been given, therefore, to assessing the economics of livestock production in small-holder farming systems in Zimbabwe (Barrett, 1991). This has provided a basis for modelling the economics of interventions into the livestock production system, such as tsetse and trypanosomiasis control; a report on this subject is currently in preparation.
Appraisal of the economic justification of trypanosomiasis control requires projection of what is likely to happen with, versus without, intervention. The robustness of the analysis is completely dependent upon the assumptions which underlie the projected scenarios, possibly more so than upon the precision with which disease impact upon livestock productivity can be measured. For this reason, the work in Zimbabwe has put emphasis on examining the assumptions which underlie the benefit-cost analysis of trypanosomiasis control (Barrett, 1989b).
In particular, attention has been given to the issue of whether land use in tsetse-free areas is likely to be sustainable. It has usually been assumed that appropriate land use plans will be prepared and implemented. Some conservationists have argued that tsetse control is promoting inappropriate and unsustainable land use in fragile environments liable to rapid and severe degradation. In Zimbabwe, the mid-Zambezi Valley is one area where such concern has been expressed. The Government of Zimbabwe and the international donor community are very sensitive to these issues. Accordingly, an interdisciplinary case study of land degradation associated with agropastoral land use in tsetse-freed parts of the midZambezi Valley was carried out in part of the Zambezi Valley, under the auspices of the Tsetse and Trypanosomiasis Control Branch (Barrett, Brinn and Timberlake, 1991).
For the international tsetse control community, the study has provided objective evidence that not all parts of Africa's tsetse-infested lands are Grenzwildnisse (Ford, 1971), tsetse-infested only because they are useless to man and intrinsically unsuited to agriculture. On the other hand, the study has shown that accelerated livestock development in an area following tsetse control can lead to environmental degradation as a consequence of inappropriate land husbandry, which needs to be addressed through appropriate agricultural extension programmes coordinated with tsetse control operations.
The study also reveals quite starkly that tsetse control is often neither necessary nor sufficient to promote livestock development in a tsetse-affected area. Livestock development is dependent upon a much broader range of factors than the veterinary situation alone: this points to the fact that economic appraisal of tsetse control operations which does not take proper account of the broader development initiatives and constraints affecting a tsetseaffected area is unlikely to be very meaningful in practice.
This study demonstrated that it is feasible, for organisations involved in the funding or implementation of tsetse and trypanosomiasis control operations, to address issues relating to land use using limited-resource studies: so-called rapid rural appraisal. Similar exercises should be carried out at other locations where environmental concerns arise in relation to tsetse and trypanosomiasis control programmes.
5. Limitations in Studies Carried out to Date
As with previous long-term economic studies of trypanosomiasis control, the Zimbabwe study was essentially an economic research project with specific objectives to address certain issues. Strategic economic studies of this nature are undoubtedly worthwhile and provide valuable insights into strategy and policy, but almost inevitably tend to be ex post (after the event) evaluations as opposed to ex ante (before the event) appraisals.
The detailed and rigorous methodologies that tend to emerge from ex post evaluations are often too sophisticated and data-demanding for application by trypanosomiasis control organizations for ex ante planning appraisal purposes on a routine basis, especially if resource allocation is being made by a manager or planner with little, if any, economics background.
Yet one of the clear messages from the economic studies carried out to date, and in particular from Zimbabwe, is that generalisation is almost impossible in respect of where and when trypanosomiasis control is justified and how such control is to be accomplished in the most cost-effective way. The entire rationale for development of economic methodologies for improved resource management disintegrates if there is no effective translation of economic research into the world of the tsetse control practitioner.
The power of economic analysis does not rest in improving our hindsight but our foresight - money spent on economic analysis is wasted if it does not improve our ability to make better decisions in the future. This is a lesson well understood by the international agencies and western donor nations, who widely employ economists to participate in decision making over resource allocation. But where are their counterparts in the trypanosomiasis control agencies of the African nations ?
I suggest that African countries with substantial tsetse and trypanosomiasis control operations should consider developing their own institutional capability for economic analysis of their activities. Indeed, Zimbabwe is already moving in this direction. Donor agencies should consider whether future economics support to tsetse and trypanosomiasis control should place more emphasis on institutional development and less on strategic studies and policy analysis by external organizations, although such studies are important and should continue.
6. Institutional Development
There are several ways in which African nations, possibly with donor assistance, could develop their own capability for economic monitoring, evaluation and appraisal of their trypanosomiasis control operations. These include:
giving economics training to senior technical staff in trypanosomiasis control organizations;
strengthening economics capability within the country outside the tsetse control agency;
establishing regional units with specific mandate to provide economics support to member nations.
Each option has its problems and none appers likely to be universally the preferred approach.
Development of an Economics Capability within the Trypanosomiasis Control Agency
Few tsetse and trypanosomiasis control organizations in Africa could justify the permanent recruitment of an economist. The work load may not be full-time. In the era of structural adjustment, African governments are trying to cut down their expenditure on the civil service, and funding for additional staff is hard to find. Even if this were feasible, such a post creates substantial institutional problems. The economist has little prospect of promotion within the organization and so is likely to leave after a short number of years in order to advance his career elsewhere. Continuity of economics support is therefore unlikely.
The alternative is to identify suitable technical staff within the organization to whom economics training can be given. This has merits in that career prospects for such individuals are likely to be enhanced within the organization rather than hindered. The disadvantage is that such staff may be able to carry out relatively routine cost analysis and even rudimentary benefit-cost analysis but will not have sufficient time, expertise or experience to carry out the in-depth strategic studies and policy analysis which may be needed.
Development of an Economics Capability outside the National Trypanosomiasis Control Agency
Many trypanosomiasis control organizations have close links to a veterinary department which usually also lacks a much-needed capability for economic analysis. There may be scope for establishing or strengthening veterinary economics and epidemiology units in tsetse-affected countries and improving the institutional linkage of such units to the trypanosomiasis control organization. This is one part of the approach being adopted in Zimbabwe. In other African countries alternative institutional linkages may be appropriate -for example with government units concerned with livestock development planning, or monitoring and evaluation of other agricultural pests and vectors.
The disadvantage of this arrangement is that the economists in such a unit are likely to be involved in a wide range of livestock disease issues other than trypanosomiasis. They may find themselves too heavily involved in other areas of work to provide the support required by the trypanosomiasis control organization, which will not have direct control over these staff.
Development of a Regional-based Economics Capability Specifically for Trypanosomiasis Control
A third possible approach is to consider the establishment of regional units to provide economics support to national trypanosomiasis control organizations in different parts of Africa. Such regional units could be funded by member countries or, possibly, through donor agencies and would hopefully be staffed by nationals from the region, perhaps after an initial phase of establishment with expatriate support.
Economics support on a regional basis would make most sense in the context of other arguments for establishment of regional units to support national tsetse and trypanosomiasis control agencies. The thrust of the present paper has been concerned with economic aspects of tsetse and trypanosomiasis control, but there are numerous other issues which are going to become increasingly important in future planning and appraisal of control operations, issues which are equally difficult for individual agencies to handle adequately with their own limited staff resources. These will include social issues, land use issues, environmental impact assessment and regional collaboration where operations cover more than one country.
Reliance on Independent Research and Advisory Organizations
The last alternative is for African governments to continue relying upon independent organizations for economics support in tsetse and trypanosomiasis control. This could include bilateral and multilateral donor funding of research intitutes, or consultancy companies, in Africa, or elsewhere, for implementation. As was discussed earlier, such sources of expertise and advice can be effective in addressing strategic issues, but are not well placed for assisting in routine economic support.
The Best Solution may be a Mix of Assistance
The alternatives discussed above are not mutually exclusive. A trypanosomiasis control organization could give its senior staff economics training to enable them to carry out cost analysis for operational planning while relying on external support, from a veterinary economics unit or a consultancy source, for its strategic study needs.
7. Trypanosomiasis Control as an Element of Sustainable Agricultural Production
The theme of this meeting, as I understand it, is that trypanosomiasis is to be viewed as one element of an overall approach to rural development in which the emphasis is on sustainable agriculture. This means improving the coordination between the planning and appraisal of tsetse control operations and rural development planning, in particular land use planning. In practice, this coordination is very difficult to achieve. The development and strengthening of the institutional capability of trypanosomiasis control organizations in the sphere of agricultural economics may contribute to more effective communication and liaison between the trypanosomiasis control organization and other agencies involved in developing a sustainable future for rural people in tsetse-affected parts of Africa.
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LE ROLE DE L'ECONOME DANS LA PLANIFICATION ET L'EVALUATION
DES OPERATIONS POUR LE CONTROLE DE LA TRYPANOSOMIASE
- L'EXPERIENCE ACCRUE AU ZIMBABWE -
Bon nombre d'études réalisées depuis le début des années 1970 ont montré que les analyses économiques ne servaient pas seulement à justifier les dépenses pour contrôler les tsé-tsé et la trypanosomiase mais pouvaient également contribuer à l'amélioration de la répartition des resources dans de telles opérations. Cet article reprend brièvement les autres études économiques qui ont été réalisées autrepart en Afrique et ensuite étudie en détail un projet d'une durée de 4 ans qui a débuté en 1987 avec pour but d'examiner les aspects économiques et sociaux du contrôle des tsé-tsé et de la trypanosomiase au Zimbabwe.
L'analyse coût-bénéfice a pris en considération l'éventuelle dégradation environnementale associée à un développement acceléré de l'élevage dans des zones infestées par les tsé-tsé au Zimbabwe et accru les connaissances sur la rentabilité de la traction animale. Des études comparatives ont couverts la pulvérisation au sol avec le DDT et les pyréthroides synthétiques, l'application par pulvérisation d'insecticides non-résiduels par avions ou hélicoptères, l'utilisation d'écrans appâtés aux odeurs et imprégnés d'insecticides et l'application de pyréthroides synthétiques sur le bétail par bains ou applications.
En tant qu'étude stratégique, le travail au Zimbabwe a fourni des méthodologies adaptées au sud de l'Afrique pour les analyses coût-bénéfice des opérations de contrôle de la trypanosomiase et des tsé-tsé et pour des analyses comparatives des coûts des différentes techniques de contrôle. Cependant, pour que des crédits soient régulièrement alloués pour ces opérations, ces méthodes doivent être proposée chaque année dans les plans de travail. Cela démontre un besoin de connaissance en matière d'analyse économique dans la maison, que le Gouvernement du Zimbabwe s'attèlle régulièrement à renforcer.
Il existe un manque apparent de connaissance des analyses économiques des opérations de contrôle de la trypanosomiase et des tsé-tsé en Afrique. Cet article démontre que la situation n'est pas adéquate et expose diverses options de développement institutionnelles afin d'améliorer la gestion des opérations de contrôle de la trypanosomiase et des tsé-tsé, en Afrique.