Rev. sci. tech. Off. int. Epiz., 1996, 15 (3), 797-812
The nature of animal health economics in
relation to veterinary epidemiology
J.E.D. MLANGWA(*,**)and K.L. SAMUI (*)
Summary: Animal health economics is being formally integrated into such
institutions as sub-Saharan African universities and Veterinary Services.
Unfortunately, the nature of the relationship between economics and
epidemiology is not clearly understood. Economics has an extensive
theoretical apparatus and an array of methods and techniques. Animal health
economics has two interrelated branches: economics for the planning and
management of animal health services and economic analysis of diseases and
interventions.
Epidemiology and economics, although separate scientific areas, are
complementary when the goal is efficient management of animal health and
associated delivery systems. In performing economic analyses, an 'economic
model' should determine data requirements (epidemiological and socio­
economic), as such analyses invariably require epidemiological inputs. The
core concepts in economic analysis are as follows: conceptual models,
opportunity cost of resources, marginal analysis and partial analysis.
Important methods include statistical models, mathematical programming,
budgets, cost minimisation, decision analysis, variants of cost-benefit analysis
and simulation.
Given the nature of animal health economics, veterinarians who want to
practise as economists need a thorough training in economic principles and
methods, in addition to training in basic epidemiology.
KEYWORDS: Animal health economics - Economics - Epidemiology and
economics - Institutional economics - Veterinary economics.
INTRODUCTION
Progress in any subject depends largely on the way in which that subject is
perceived by practitioners in the discipline, and the way in which future practitioners
are trained. Animal health economics appears to be a fashionable subject in Africa at
present, as shown by the development of Veterinary Epidemiology Units in countries
such as Kenya, Tanzania and Zambia, and by the establishment of epidemiology and
economics courses at both undergraduate and post-graduate levels in sub-Saharan
African universities (38, 39; J. Cleese, personal communication).
* School of Veterinary Medicine, University of Zambia, P.O. Box 32379, Lusaka, Zambia.
** Department of Veterinary Medicine and Public Health, Sokoine University of Agriculture,
P.O. Box 3021, Morogoro, Tanzania (to 30 June 1997).
798
On an historical note, veterinarians, especially epidemiologists, being practical in
approach, have not wanted to limit veterinary work purely to technical areas and, as
a result, have also entered the field of the socio-economics of animal health.
Unfortunately, there appears to be some misconception as to the nature of animal
health economics (what it is and how it should be applied to increase the efficiency
of animal production systems and product marketing chains) in relation to veterinary
epidemiology. To quote Grindle, 'The rigor which epidemiologists apply to their own
scientific area should apply when they cross the disciplinary boundaries into financial
and economic analysis' (19). This paper addresses the issue, in addition to exploring
the implications for the practice of and training in economics.
ANIMAL HEALTH ECONOMICS
Economics is a science of making choices. It analyses allocation of scarce resources
in the realm of competing human demands. Economics is divided into
microeconomics, which deals with economic principles and methods relevant to a
particular sector of the economy, and macroeconomics, which studies the economy as
a whole, i.e. economic aggregates and interrelationships between sectors. The field of
agricultural economics has been developed to deal with problems in the agricultural
sector, including links between agriculture and other sectors of the economy (7).
Economics comprises both economic theory and methods, which form the
framework or tool kit used to analyse economic problems or to plan for the future (12,
30). To apply economic principles to agriculture effectively, the economist must also
understand the biology of agricultural production (12).
Animal health economics is the area of economics or, more particularly, of
agricultural economics that applies the principles and methods of economic analysis
to animal health problems. The need for veterinarians with economic skills in
sub-Saharan Africa has already been described (35, 37).
Institutional economics is a useful addition to neo-classical economics when
analysing animal health problems. Institutional economics may be described as the
economic analysis of organisations and other economic agents, taking into
consideration transaction costs and the roles of incentives and social institutions (28).
Institutionalists seek to understand what motivates economic agents in order to
develop effective reform strategies, e.g. privatisation of delivery systems (44).
In animal health economics, the task is either to analyse the consequences of a
change, e.g. introducing a new vaccine or policy, or to make a judgement on how
desirable such a change would be. The former activity falls into the category of
positive economics, whereas the latter is normative economics (26). Normative
economics, or welfare economics, evaluates the consequences of proposed changes
and makes recommendations on the desirability of such changes. It is prescriptive and
value judgements are involved. Economic policy may be placed in the category of
normative economics.
As regards the scope of animal health economics, most of the work reported in
veterinary journals has been in the area of losses due to diseases and cost-benefit
analysis of control strategies. This work may be called the economic analysis of animal
diseases and intervention strategies. In the past, little use was made of economic
principles and methods to analyse veterinary delivery systems and the management of
799
such systems (animal health services economics). This situation appears to be
changing, with recent contributions from livestock development specialists, political
scientists, economists and veterinarians, who are all concerned with the management
of veterinary delivery systems, especially in developing countries. Economics has
made a positive contribution to the analysis of:
- financing of veterinary delivery services in Africa (2)
- provision of Veterinary Services and the roles of the State and the private sector
in such provision (9, 10, 27, 28, 36, 47)
- planning for staff, budgeting and public finance (25).
Animal health economics should encompass the following components:
- animal health services economics (management and economics of delivery
systems, veterinary finance and animal health policy analysis)
- economic analysis of animal diseases and intervention strategies, including the
efficiency and equity of veterinary interventions.
THEORY, CONCEPTS, MODELS, METHODS AND
TECHNIQUES IN ANIMAL HEALTH ECONOMICS
There is a need to distinguish between economic theory (concepts and models),
methods and techniques.
A concept is an idea or general notion which is an abstraction from the particular.
Concepts help to simplify and classify our observations about the real world (21).
Some examples of important concepts in economics are the notions of the marginal
principle, the opportunity cost and the disease cost. The disease cost concept evaluates
the losses caused by a disease, plus the expenditure incurred in lessening the effect of
that disease (32).
Methods are general and widely applicable procedures or plans of action or enquiry
for solving problems (e.g. budgeting), whereas techniques are typically variations of
particular methods, and apply to relatively specific contexts, for example, partial
budgeting (16). Techniques abound in applied fields.
Economic theory is a collection of interrelated propositions or hypotheses. These
hypotheses take the form of models of economic behaviour, with each model capable
of being tested empirically. Economic models are abstract, logical constructs
comprising two components: assumptions and the implications of such assumptions
(43). Theory may be used to describe, explain or predict the economic behaviour of
agents or economic variables. Furthermore, theory guides research. It is theory,
therefore, that guides economists in choosing appropriate concepts, models, methods
and techniques for investigating economic problems and for analysing data in both
basic and applied work.
Most of the work on animal health delivery systems uses extensive economic theory
with little statistical analysis (2, 9, 10, 27, 28, 36, 47) but, as the field develops, one
would expect to see the application of more statistical and econometric methods and
techniques. Methods and techniques in animal health economics will be discussed after
this paper has analysed the relationship between animal health economics and
800
veterinary epidemiology. This analysis will place the two closely related applied
sciences in context and guide the reader in designing appropriate research programmes
to generate data required in economic analyses of animal health problems.
ANIMAL HEALTH ECONOMICS AND VETERINARY
EPIDEMIOLOGY
There are two principal ways of classifying the relationship between animal health
economics and veterinary epidemiology: the hierarchical classification and the
methodological classification.
Hierarchical classification
Under hierarchical classification, two approaches have
consider that animal health economics is an integral part of
(1, 2 1 , 22). This is also implicitly acknowledged in some
texts, in which there is, usually, only one chapter devoted to
(48, 49).
been used. First, some
veterinary epidemiology
veterinary epidemiology
animal health economics
For example, one textbook defines epidemiology as the study of the behaviour and
determinants of disease and impaired productivity in populations; a study whose
purpose is to recommend actions for prevention, control or treatment of the problem
being studied (1). Epidemiology is further described as an eclectic field, primarily
combining concepts, methods and methodologies of medicine, biology, mathematics,
statistics, economics and management to achieve objectives.
The second approach is to regard animal health economics and veterinary
epidemiology as complementary subjects in the wider field of animal health. This is
the view taken by three textbooks (33, 45, 50). Interestingly, most leading texts of
medical epidemiology do not cover topics of medical economics (20, 29, 34). Such
topics are covered in separate texts, such as those by Drummond and Drummond et
al., thus making a clear distinction between medical epidemiology and health
economics (14, 15). However, the economics texts do emphasise the role of
epidemiology in economic analysis.
Methodological classification
In the literature on animal health economics - more specifically on the economics
of disease and disease control - again, one finds two types of approach.
First, there is the 'epidemiology-centred approach', whereby economic values (such
as costs and revenues) are attached to epidemiological results to obtain the cost of
diseases or the economic benefit from controlling diseases.
The 'economic model-centred approach' argues that the economic framework,
usually a model, is the most fundamental component in the economic analysis of
diseases and disease control. The model should, where appropriate, be informed by
both economic and epidemiological data. The main proponents of this approach are
economists. There is also a new breed of 'veterinary economists' who employ this
method. The case for the 'economic model first approach' has been well argued by
Howe, Grindle, McInerney et al. and Buhr et al. (5, 19, 23, 30, 32).
801
It is almost universally accepted that epidemiological theories and methods are
distinct from economic theories and methods and, in fact, one may perform an
epidemiological study without the use of economics. The reverse is difficult to prove
even in purely theoretical analysis.
The hierarchical classification and the methodological classification are not
exclusive. Moreover, and importantly, these two ways of regarding the relationship
between epidemiology and economics are not mirror images, in terms of the further
divisions to be found within each method. The methodological classification is more
profound than the hierarchical classification. Most articles on veterinary economics in
veterinary journals show this distinction between the two approaches (23, 32). This
issue has a bearing on the development of veterinary epidemiology and economics in
sub-Saharan Africa, as choices have to be made among different graduate programmes
required to train professional staff. Training courses in sub-Saharan Africa are likely
to reflect the particular approach favoured by the developers of these courses.
METHODS AND TECHNIQUES IN ANIMAL HEALTH
ECONOMICS
Choice and opportunity costs
In the traditional area of the economics of disease loss and disease control, many
methods and techniques have been used for analysis. The idea of choice is central to
any economic analysis. The basic premise in analysis is to compare a single disease
control strategy with the consequences of doing nothing.
In allocating resources to one activity (say, activity A), rather than to other activities
(ranging from B to Z), a cost is incurred. Economists call this the opportunity cost of
a decision, i.e. the benefit that one foregoes by not selecting the best alternative course
of action among the choices available (B). The benefit obtained from performing A can
then be compared with the associated economic cost of carrying out B, i.e. the
opportunity cost. As long as this benefit exceeds the cost of B, project A is worth
undertaking. In animal health one examines the marginal gain of this allocation against
the marginal cost (the opportunity cost). Using this methodology, one can rank
different activities on the basis of net benefit value, in descending order of preference.
Although the opportunity cost is real, it is convenient, when analysing the costs of
economic activities, to value such activities in common monetary accounting units,
such as the dollar (43). In economies without distortions, the economic cost will be
equal to the historic cost using actual prices paid. Where there are distortions, the two
types of costs diverge. It is therefore important that any economic analysis should be
consistent in pricing inputs and outputs. This consistency can be achieved either by
using historic prices (financial analysis - which may be regarded as an exercise in
accounting) or by using the real economic cost (the opportunity cost), in which case
all price distortions must be identified and corrected.
The marginal principle
When shifting resources from one activity to another, one should examine what
happens at the margin by comparing the extra benefit that will result from this shift
802
and the opportunity cost of the extra resources. Economic theory states that one should
spend more and more resources until the point at which an additional dollar spent earns
exactly one dollar. This is the marginal principle of all economic analyses (32). Thus,
in carrying out economic evaluation of animal diseases, one has to apply the two
concepts of opportunity cost and marginal principle consistently. McInerney further
argues that in animal health economics one should examine the avoidable losses and
not the total cost of disease (30, 32).
Partial analysis
In economic and financial analyses, comparing the situation without the project to
the situation with the project (the 'with and without project methodology') is
preferable to comparing the situation before the project with the situation after the
project (the 'before and after methodology'). By using the 'with and without project
methodology', one can correctly attribute the net benefit to the project in question (18,
45). This 'with and without' methodology is closer to experimental methodology than
the 'before and after' methodology. The basic structure of the analysis compares
(marginal) changes in costs and benefits which result from undertaking the project.
This is called the partial analysis approach (45).
Level and type of analysis and data requirements
Within any economy, animal diseases will affect the following groups: producers,
consumers, associated agribusiness, government and society. In any analysis,
therefore, one must:
- decide on whose behalf the analysis is being conducted
- identify the relevant costs and benefits to these groups (11, 46).
Table I provides a guide.
In order to measure the effect of disease on economic agents, the following
information is required:
- data on changes in productivity and production (e.g. mortality, daily weight gain,
etc.)
- socio-economic data (e.g. use of labour and services) on the farm and off the
farm, depending on the level of analysis.
It is not an easy task to isolate and quantify the impact of an animal disease because
the effects:
- are not always obvious and pronounced
- are influenced by other factors, such as management and environment (i.e.
production and productivity losses can have causes other than diseases and are thus
multifactorial)
- will be different at different stages in time, thus adding to the complexity of
evaluating the impact of the disease
- are often seen in a complex with other diseases (40).
A number of mathematical and 'simulation' models have been developed in an
attempt to try to isolate the effect of disease on livestock and the livestock industry.
803
TABLE I
Losses due to animal diseases, considered at different economic levels
Economic level
Endemic disease (A)
Non-endemic disease (B)
Foreign trade
No restriction on
restriction (Bl)
foreign trade (B2)
1. Farm or herd
(individual
producer)
Direct relationship
between loss and degree
of occurrence of the
disease per farm or herd
Large incidental
loss, even if the
farm or herd is
not affected by
the disease
(possible
compensation for
destroyed
animals)
Great loss for
affected farms or
herds (possible
compensation for
destroyed
animals); an
advantage for
farms and herds
not affected by the
disease
2.
Sector (national herd)
Loss, insofar as the price
does not adapt. In a
sufficiently large market
(e.g. the EU), hardly any
relation between level of
disease and income of
producers, owing to
price adjustment
Significant loss,
particularly in
the case of
export products,
resulting from
dropping prices
due to
decreasing
demand
Moderate loss
(depending on
possible
compensation and
on degree of price
adaptation)
3.
Supply and
processing
industries;
service and
trade *
Pro memoria
Pro memoria
Pro memoria
4.
Consumer
Loss due to higher
prices; in case of
zoonoses, loss due to
morbidity and mortality
Incidental
advantage
Slight loss
5.
Society
(national
economy)
Loss due to inefficient
use of resources
Disadvantage
considerably less
than loss to
sector (national
herd) (2.B1)
Disadvantage can
be greater than
total loss to the
national herd
(2.B2), but less
than loss to
society (national
economy) (5.B1)
* Possible effects have not been specified. Price changes are presumed to pass to the consumer immediately
and completely
EU: European Union
Source: Adapted from Renkema (46), with minor modifications
804
Useful models are those that treat disease as an economic phenomenon, and identify
all the ways in which the disease impinges on economic values. Such models should
start from the animal herd, developing links that encompass the entire livestock sector
and the wider .economic system. This entails linking epidemiological models and
adding data to the economic models (Fig. 1).
FIG. 1
Linking epidemiological models and data to economic models in
animal health economics
The economic model then indicates what type of data and what level of aggregation
are required. The data, in turn, are obtained via socio-economic surveys and
epidemiological investigations. Hence, economic analysis demands the integration of
both epidemiology and economics (5, 30). Models used include theoretical economics
models (e.g. farm-level models and industry-level conceptual models) and those given
below.
Techniques
Quantitative modelling
techniques
Quantitive modelling techniques may be used to forecast technical and socio­
economic quantities or to study associations. Statistical and epidemiological models
are explained by Ngategize and Kaneene (40), whereas Hurd and Kaneene review in
detail the application of 'simulation' models (24). Vagsholm, Vagsholm et al,
Carpenter and Buhr et al. show the usefulness of econometric methods in dealing with
repeated measures and simultaneous relationships in both epidemiology and
economics (5, 6, 5 1 , 52). The use of 'economic' quantitative modelling techniques in
livestock health and disease control decision-making is reviewed by Bennet (3),
Dijkhuizen et al. (11), Ngategize and Kaneene (40), Renkema (46) and Ellis and
James (17).
805
Decision
analysis
Decision analysis techniques are helpful when making choices under conditions of
uncertainty, especially with complex but poorly structured economic problems. Risk
analysis is incorporated in the technique. Data on risk probabilities (empirical or
imputed) are essential. The technique can be used at the producer level or at higher
levels of aggregation. Techniques used may be divided into the following:
-
mathematical
- process diagrams
- pay off matrices
- decision trees.
Ngategize et al. give a good description of decision analysis in animal health
programmes (41). Davidson et al. also provide an example of this approach in relation
to thrombo-embolic meningo-encephalitis in feedlot cattle (8).
Simulation
Simulation attempts to mimic real-life occurrences of variables (states and
quantities) over time. Figure 1 demonstrates the link between the epidemiological
model/input and the economic model. Epidemiological simulation can take one of two
forms. Either individual animals within a herd are 'observed' over time, their states
changing stochastically, i.e. as governed by the laws of probability. Alternatively, a
herd of animals is moved through time, with these animals changing states
deterministically using fixed transition coefficients. In stochastic modelling, risk is
taken into consideration by the use of probability distributions (i.e. Markov chain
models) or by using random numbers drawn from probability distributions (i.e. Monte
Carlo simulation). Simulation is a non-optimising method useful in analysing variable
dynamics in different scenarios. Economic variables may also be simulated (3).
Optimising mathematical
models
Optimising mathematical models makes use of linear programming and variants
which, although purely mathematical procedures, are useful aids in resource allocation
work where constraints abound (3, 11, 40).
Budgeting techniques and cost analysis in animal health
economics
Budgets are a planning tool in animal health economics (Table II). Partial budgets
use the partial analysis methodology.
Cost-benefit
analysis
When the planning framework covers more than one year, cost-benefit analysis,
employing the methodology of partial analysis, is the technique used. The main
variations are given in Table III.
806
TABLE II
Budgets and cost analysis in animal health economics
Reference
Level of analysis
Technique
Indicator
Farm/producer/
herd
Enterprise budget
Gross margin
(53)
Total disease cost
minimisation
Loss expenditure frontier
and avoidable losses
(32)
Partial budget
Incremental net gain as net
profit or gross margin
(32)
A s the plan covers m o r e than o n e year, adjustments should be m a d e for time value
of m o n e y (opportunity cost o f capital), inflation and uncertainty (about values o f
variables and relationships b e t w e e n variables in d y n a m i c p r o c e s s e s ) (Table IV). T h e
analysis should also take into consideration the attitude o f the 'decision-maker' to risk.
TABLE III
Cost-benefit analysis in animal health economics
Level of analysis
Technique (indicator)
Basic concept
Farm/herd level
Net present value (NPV) *
Partial budget set up over
time
National or subnational herd
As above but higher level
of aggregation (NPV) .
Shifts in supply and demand
possible
-
Industry level
analysis
Cost-benefit analysis
(NPV)
Shifts in supply and demand
(5)
Social cost-benefit analysis
(NPV)
Differential weighting of costs
and benefits according to
socio-economic strata of
stakeholders affected
(4)
Cost-effectiveness (natural
units, e.g. number of
animals vaccinated per
$100 spent)
Goal is to produce desired
outcome at least cost
All levels
Reference
• (17)
(15)
* McInerney (31) shows the superiority of the NPV criterion over the internal rate of return and the benefit
cost ratio when ranking projects. The NPV is based on marginalist principles, whereas the other two are not
807
TABLE I V
Techniques for incorporating time value of money, inflation uncertainty and
uncertainty into an analysis
Problem
Technique
Purpose
Time value of money
Timing consumption
Discounting using interest
rates
Have comparable monetary flows
Inflation
Use real values
Remove the effect of inflation
Uncertainty
Sensitivity analysis
To test the effect of variations in
the basic assumptions used in
economic analysis
Risk (probability of
outcome known
subjectively or
empirically)
Risk analysis
(26)
Decision analysis
(see above)
To compute the value of different
courses of action by incorporating
risk (probabilities) and attitude
towards risk into the analysis
IMPLICATIONS FOR INSTITUTIONALISATION OF ANIMAL
HEALTH ECONOMICS
Mlangwa and Kisauzi have described the need to teach economics in the
undergraduate curriculum in sub-Saharan Africa, in addition to examining the
organisation of such courses, the curriculum and the resources required (35).
The authors have described how economic analysis is the application of economic
methods based on the theoretical framework (i.e. concepts and principles).
Veterinarians wanting to practise as economists (working in research, animal health
policy formulation and evaluation or economic analysis of interventions) should be
thoroughly trained in economic theory and methods, preferably via courses in
agricultural economics, including macroeconomics or the links between macro and
micro economics. These courses should be supplemented by training in
epidemiological principles and methods. Sub-Saharan Africa needs to institutionalise
animal health economics and policy, and to offer graduate-level courses in veterinary
economics (39, 42). The objective must be to ensure that agricultural economists
become interested in animal health economics, or that veterinarians are trained as
animal health economists, or both. Since conversion courses (foundation or remedial
economics courses) are now available in a number of universities, the option of training
veterinarians in economics is quite feasible, and indeed there are several veterinarians
who are already well trained in economic theory and methods. Dorn predicts that more
veterinarians with graduate training in economics will be needed (13).
The need for, and training of, economists should be given due attention by
veterinary epidemiology and economics units in universities, government and the
private sector. It is not simply a question of asking a person who has been trained as
an epidemiologist to work as an economist. At the same time, epidemiologists should
be encouraged to take basic courses in economic theory and methods in order to
collaborate effectively with economists.
808
CONCLUSION
For the successful institutionalisation of animal health economics in veterinary
delivery systems, it is essential that the nature of economics and the relationship
between economics and epidemiology is understood. Whether one regards economics
as a part of epidemiology, or as a distinct discipline, the theoretical basis of economics
is so comprehensive and so fundamentally different from the basis of epidemiology
that any person wishing to practise as an economist must undergo a thorough training
in the theory and methods of this discipline.
*
* *
RELATIONS
ENTRE L'ÉCONOMIE
DE LA SANTÉ ANIMALE
L'ÉPIDÉMIOLOGIE VÉTÉRINAIRE. - J.E.D. Mlangwa et K.L. Samui.
Résumé : En Afrique subsaharienne, l'économie de la santé animale est une
discipline actuellement traitée au sein d'institutions telles que les universités et
les Services vétérinaires. Malheureusement, la nature des relations entre
l'économie et l'épidémiologie n'est pas toujours clairement comprise.
L'économie est un système théorique très élaboré qui comprend également une
multitude de méthodes et de techniques. L'économie de la santé animale
comporte deux branches étroitement liées : l'économie de la planification et de
la gestion des services de santé animale, d'une part, et l'analyse de l'impact
économique des maladies et des interventions prophylactiques, d'autre part.
Tout en constituant deux disciplines distinctes, l'épidémiologie et
l'économie sont complémentaires dès lors qu'il s'agit de gérer efficacement la
santé animale et les programmes zoosanitaires. Lors des analyses
économiques, un « modèle économique » permet de déterminer les besoins en
données (épidémiologiques et socio-économiques), car ce type d'analyse
nécessite systématiquement des informations épidémiologiques. Les concepts
de base de l'analyse économique sont les suivants : modèles conceptuels, coûts
d'opportunité des ressources, étude de rentabilité et analyse partielle. Les
principales méthodes incluent les modèles statistiques, la programmation
mathématique, l'élaboration des budgets, la réduction des coûts, l'analyse des
décisions, les variantes des analyses coûts-bénéfices et la simulation.
Etant donnée la nature de l'économie de la santé animale, les vétérinaires
qui se veulent économistes doivent acquérir, outre des connaissances de base
en épidémiologie, une formation complète sur les principes et les méthodes
économiques.
MOTS-CLÉS : Economie - Economie de la santé animale - Economie des
administrations publiques - Economie vétérinaire - Epidémiologie et
économie.
ET
809
LA NATURALEZA DE LA ECONOMÍA DE LA SANIDAD ANIMAL CON
RELACIÓN A LA EPIDEMIOLOGÍA VETERINARIA. - J.E.D. Mlangwa y
K.L. Samui.
Resumen: A nivel formal, la economía de la sanidad animal es una disciplina
que instituciones tales como universidades y Servicios veterinarios del Africa
sub-sahariana han ido integrando. Lamentablemente, la naturaleza de las
relaciones existentes entre economía y epidemiología no ha sido comprendida
aún con claridad. La economía posee un vasto aparato teórico y dispone de
múltiples métodos y técnicas. La economía de la sanidad animal tiene dos
ramas relacionadas entre sí: la economía de la planificación y gestión de los
servicios de sanidad animal y el análisis económico de las enfermedades e
intervenciones sanitarias.
Aunque constituyan dos campos científicos independientes, la epidemiología
y la economía resultan complementarias cuando el objetivo es un manejo
eficaz de la sanidad animal y de los sistemas asociados a ésta. La realización
de análisis económicos exige la utilización de un «modelo económico» que
determine las necesidades existentes en cuanto a datos (epidemiológicos y
socioeconómicos), pues este tipo de análisis requiere invariablemente
informaciones de tipo epidemiológico. En la realización de análisis
económicos, los conceptos fundamentales son los siguientes: modelos
conceptuales, coste de oportunidad de los recursos, análisis marginal y
análisis parcial. Los métodos más importantes comprenden modelos
estadísticos, programación
matemática,
realización de presupuestos,
minimización de costes, análisis de decisiones, variantes del análisis de
costes-beneficios y simulaciones.
Dada la naturaleza de la economía de la sanidad animal, los veterinarios
que quieran ejercer de economistas necesitan una formación completa en
materia de principios y métodos de economía, además de una formación en
epidemiología básica.
PALABRAS CLAVE: Economía - Economía de la sanidad animal Economía institucional - Economía veterinaria - Epidemiología y economía.
*
* *
REFERENCES
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Centre for Africa (ILCA), Addis Ababa, 131 pp.
3. BENNET R . M . (1992). - The use of 'economic' quantitative modelling techniques in
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