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Cost-effective disease control routines and animal health management in animal agriculture

by S. Chema and D. Ward


Developing countries, with a few exceptions, inherited livestock research and development systems they had little or no hand in designing. These have not, in the main, performed well. Given current and probable future dependence on external donor support, programme conceptualization in these countries is likely to largely remain in other hands. This is happening at a time when scientific manpower in the livestock sub-sector has been improving. At the same time, the better Third World scientists are faced with diminishing operational support and personal incomes and are opting out of public sector institutions and often out of their countries.

Rapidly increasing populations and socio-political instability in much of the developing world have added to the pressure to find lasting solutions.

Animal diseases were for many years recognized as important constraints to livestock production and formed a predominant portion of donor funded programmes. For the past two decades, increasing the numbers of veterinarians through the establishment of veterinary colleges and training facilities for paraveterinary personnel has been a major preoccupation.

In recent years however, views and estimates have been given about the number of animal health personnel needed to adequately service a given number of livestock units under various conditions (SEDES/FAO, 1977; Sandford, 1983). What the more recent studies state is that in absolute national terms, where the number of livestock units is simply divided by the number of veterinary personnel, many countries, even in Africa the worst endowed continent, are attaining the required theoretical ratios (Table 1). Favourable national ratios on a macro-scale have not always been translated into expertise available at producer level. The most persistent of the reasons given for this are:

Table 1. Ratio of Livestock Units (×1000) to Government Veterinary Staff in Sub-saharan Africa

E. & South120:180:114:16:1

In research, which has over the years been much more dependent on external financing than field services and where the percentage of expatriates has been substantial, there have been major shifts in donor policy in recent years. After years of uncoordinated donor support recent moves have been towards promotion of regional cooperation and coordinated donor funding. Networking has been an important element in cooperative programmes. The CGIAR Centres have been promoted by most donors as the main hubs for networking activities.

Persistence of animal health problems in the presence of local experts has not boosted their morale or enhanced their standing in the eyes of the affected farming public. Frustration has ensured at various level and has tended to be especially pronounced among those who have greatest drive, superior ability or training. This has in turn encouraged staff instability due to movement out of public service to other sectors or reluctance to return home for those in training outside their countries.


A primary reason for establishment of veterinary services in most of the developing countries was for the control of epizootic diseases. Rinderpest and contagious bovine pleuropneumonia (CBPP) were the first cattle diseases targeted.

As the animal health situation improved and livestock improvement programmes were instituted, other diseases such as foot and mouth disease became important. Another prerequisite for disease control was the establishment of diagnostic facilities. Still later, many countries took the decision to establish vaccine production laboratories.

Besides epizootic diseases, there was early recognition of the limits that a number of enzootic diseases placed on livestock improvement. These included many viral and bacterial diseases and arthropodborne protozoal/rickettsial diseases such as trypanosomiasis, theileriosis, babesiosis and anaplasmosis.

Through the existence of diagnostic facilities, many diseases hitherto unknown were identified. Not all were of national importance but which, in the absence of alternative disease control services, veterinary departments, being public institutions, felt obligated to deal with. The same rationale was subsequently used to extend public services to clinical veterinary practice.

Control of Epizootics

The Example of Rinderpest: Rinderpest is recognized as the most devastating of all livestock diseases and its control has served as a prototype for the control of other epizootics. Though now controlled in all continents with the exception of Africa and Asia, the potential devastating effect of this disease is well known. In the Great African Pandemic of 1880–95, rinderpest is estimated to have killed 80–90 percent of Africa's cattle and wild ruminants (Faulkner, 1983). The more recent epizootic of 1981–1983 is estimated to have caused an economic loss of US$ 300 million (de Haan and Nissen, 1985). Given the devastating mortality rinderpest has caused over the years, justification for its control appeared self-evident not only for the particular country affected but for neighbours and importers of livestock and livestock products.

The method used for rinderpest control using large coordinated national and regional campaigns has been effective, although inability to reach all animals at risk has made it impossible to eradicate the disease.

Vaccination coverage is always maximal during actual or threatened disease outbreaks when the cooperation between livestock owners and vaccinators is at its peak. This cooperation does however fall off rapidly as soon as mortalities cease and cattle owners do not feel an immediate threat. Table 2 shows the estimated vaccine coverage for rinderpest and contagious bovine pleuropneumonia (CBPP) in various African regions during the 1970s. One result of the decreasing vaccination coverage was that, by 1985, rinderpest had reoccurred throughout the Sahel, West, Central and East Africa.

Table 2. Rinderpest & CBPP Vaccination Coverage (%) in Sub-saharan Africa

S/Humid Anglo.
West Africa
S/Humid Franco.
West Africa

Cost Effectiveness of Epizootic Control: As was demonstrated during the special rinderpest disease control programme of 1962–76 in Africa (Joint Project 15) and as is evident from results to date in the ongoing Pan African Rinderpest Campaign, that it is technically easy to control the disease, but control is much more cost effective in an atmosphere of political tranquillity. Attempting to reach areas of political conflict considerably adds to the cost and reduces vaccination efficiency.

There have been recent advances in rinderpest vaccine development aimed at further increasing the effectiveness and reducing the cost of rinderpest control. Among these is the recent demonstration of protection by a vectored recombinant vaccine (Yilma et al., 1988) and the reported thermostable vaccine whose economic value has recently been analyzed (Stryker et al., 1988).

The likely benefits of vaccine vectored by the thermostable pox viruses are high even without considering the potential use of these viruses as vectors for a multiplicity of disease immunogens. Besides the elimination or at least the reduced need to maintain the cold chain in vaccine storage and transportation, it is claimed that the vaccines could be produced at greatly reduced costs. Before any benefits are realized, however, the whole concept of vectored vaccines will have to gain wider acceptance and the current widespread rejection of vaccinia as a suitable and safe vector will have to be overcome. There is already much activity in developing alternative animal poxvirus vectors including capripox and fowlpox which, unlike vaccinia, have no significant pathogenicity for humans.

Economic calculations for the thermostable vaccine have given internal rates of return of up to 0.22 even when used to immunize relatively modest numbers of cattle.

Apportionment of Costs: Generally, the control of epizootics is perceived as a public good and paid for directly by the government although some countries have successfully introduced at least partial payment by cattle owners for these services. Recent experience in West Africa indicates willingness of producers to contribute to the cost of controlling rinderpest (de Haan and Bekure, 1990). The viability and sustainability of government veterinary services in developing countries would be substantially improved by taking advantage of this willingness on the part of livestock producers to pay for services.

Control of Foot and Mouth Disease As an Epizootic: Although capable of causing some mortality in traditionally kept livestock, many cattle owners fail to recognize foot and mouth disease (FMD) as an economically important disease. For this reason there is considerable resistance when they are called upon to pay for its control. In those countries which have an export market for cattle or their products, however, lost markets as a result of disease are readily appreciated and producer cooperation is easy.

In the case of FMD, regional agreement about its control would be desirable. Because of the multiplicity of FMD virus types and sub-types and the necessity to ensure monitoring of sub-type changes, the control of this disease will require regulation by government veterinary services. Diagnosis, quarantine, virus typing, vaccine production and coverage are all key steps in FMD control which require coordination and centralized authority. Many Latin American countries have lost this authority due to weakening of government veterinary services. Consequently the key steps are not coordinated for maximum effectiveness and often vaccine virus type is not related to virus type causing disease, vaccination coverage is haphazard and frequently ineffective. Until this situation is corrected, it will be biologically impossible to control, much less eradicate, FMD in these areas and any efforts will not be cost effective.

Not all countries place equal importance on FMD control. Emphasis is usually determined by the incentives of export markets for livestock and livestock products. Although it is technically feasible to control FMD, it is impractical in most countries where there are no incentives such as export markets.

Control of Newcastle Disease: Reliable figures on the importance of poultry in the diet or economy of various countries are difficult to obtain. This may have contributed to the slow progress in the control of poultry diseases. Newcastle disease constitutes the most important epizootic disease of poultry and is a serious constraint to the production of a cheap animal protein. Where its control has been routinely practiced, use has been made of the standard vaccine, which like most other live viral vaccines, depends on the availability of a cold chain to maintain efficacy. Proof of the effectiveness of the thermostable oral vaccine and the successful promotion of its use would constitute an important step in increasing the effectiveness of Newcastle Disease control especially if it can remain stable in the wide variety of poultry feeds used in village situations.

The delay in the use of the oral thermostable Newcastle disease vaccine is puzzling and reasons for it ought to be investigated and impediments removed.

It is concluded therefore that practical methods for controlling epizootics do exist and beneficiaries are willing to contribute for their control or eradication. Policy backup is however required from governments to ensure that funds are made available to sustain disease control. This could be either through subvention of a higher proportion of the livestock contribution to gross national product or by a more rigorous programme to have beneficiaries pay for services either directly or through a system of cess.

Control of Enzootic Diseases of Economic Importance

In this category are included tick-borne diseases, trypanosomiasis, dermatophilosis and a number of viral diseases many of which are arthropod-borne. Although their routine control has traditionally been within the public sector purview, there is little doubt that most of the benefits accruing from their control go to individual livestock owners. In the past, methods for their control were too costly or not readily available to individuals. However, emerging technology is increasingly simplifying control and avenues are opening which should make it more cost-effective to have control provided by the government on a cost-recovery basis or done by the private sector and paid for by direct beneficiaries.

Tick-borne Diseases: Tick-borne diseases caused by Anaplasma, Babesia, Theileria and Cowdria species are of major importance throughout the tropics and subtropics. For many years their control relied heavily on vector control through the use of acaricides. The expense of these chemicals and reliance on costly modes of application using dipping tanks or spray races have meant that combating these diseases in most developing countries was a community centred effort often borne entirely by the government. This has been especially the case where livestock improvement programmes have been based on introduced exotic animals. Under those conditions enzootic stability, which protects indigenous livestock from unacceptably high mortality, could not be relied upon.

Factors which favour more cost-effective tick-borne disease control include:

A measure of the utility of tick control in a given community has been the degree to which the operation of dips has been effectively taken over by the beneficiaries or the government has been able to continue running communal dips on a cost-recovery basis. When the main reason for using dips has been coercion through legislation and where the predominant breeds have been indigenous, farmers have often quickly discovered that not dipping their animals resulted in no substantial economic loss. Such systems are therefore essentially not cost-effective from the point of view of the farmer and should be re-examined or abandoned.

Tse-tse and Trypanosomiasis Control: Although it occurs in areas on other continents, trypanosomiasis is of special importance in Africa where its presence is associated with the tse-tse fly and where the disease in livestock co-exists with human sleeping sickness. The disease tends to cover large areas coinciding with the tse-tse habitat. For these reasons control of trypanosomiasis has traditionally been in the public domain. Routine control methods have been:

• Vector control through:

Many people have questioned the desirability of opening large tracts of land to livestock through the control of tse-tse and the possible consequences of land degradation. Because of the need to encourage efficient utilization of land, it is inevitable that people will eventually move into these areas as long as there are no effective measures of human population control.

Clinical Interventions

In many countries of the developing world clinical services have traditionally been provided by the government, often free of charge or heavily subsidized.

Factors which have contributed to less public sector financing of clinical veterinary services have included:

As a result of these changes, a number of evolutionary developments with implications for greater cost-effectiveness are taking place. Among these changes are:

Control of Helminthiasis

Tropics and subtropics offer ideal environments for helminths. Despite this and the well documented economic importance of endoparasites, their control is accorded low priority in developing countries. A factor in this neglect is no doubt their insidious nature in the more valuable adult animal.

Another, probably more crucial reason, is the lack of progress in the development of effective vaccines and the overwhelming reliance on the use of imported, and therefore expensive, anthelmintic drugs. Where anthelmintics are in extensive use, resistance often develops and laborious techniques are required to determine the degree of resistance and possible alternative drugs. Although many species of roundworms and flatworms are important in developing countries, perhaps the most devastating are Haemonchus contortus and Fasciola species.

In the tropics where the value of pasture rotation appears to be limited, reliance will continue to be placed on the use of anthelmintics, the administration frequency of which will have to be established in each given situation. The selection of the drug to use will often be an important consideration and facilities may need to be established on a regional basis for testing against resistance to given classes of anthelmintics with a view to using the cheapest, narrowest spectrum product needed to control the important helminth. This will guard against the tendency, widely promoted by drug companies, to utilize anthelmintics of ever increasing broad spectrum.

There may be merit in giving attention to emerging initiatives in a number of countries to investigate the usefulness of indigenous vermifuges derived from local plants.

Many research groups in various parts of the world are now engaged in tests aimed at developing a vaccine against haemonchosis. If initial promise is borne out, success in this will have a profound effect on the cost-effectiveness of controlling the most important internal parasite affecting ruminants.


After years of debate and reflection, there is now relatively little doubt about the desirability of having owners pay for clinical services rendered to individual animals. This especially applies for afflictions which do not pose an immediate threat of spreading disastrously to other livestock.

Spurred on by the inadequacy of funds to finance urgent needs, such as the control of epizootics, governments are now increasingly willing to try a number of alternative ways of providing these services. Table 3 lists alternative mechanisms which are being supported by international donors and implemented in various African countries. These schemes employ various mechanisms for cost recovery of veterinary drug or vaccination distribution, delivery of veterinary services by pareveterinarians, private practioners or herder associations (de Haan and Bekure, 1990). Evidence to date is that in the face of full cost recovery, drug availability increased (CAR), drug purchases by poorer livestock owners increased (CAR) and rinderpest vaccination coverage was not adversely affected (Burkina Faso, CAR, Mali and Mauritania).


Routine disease control depends heavily on two main supports, namely, a diagnostic service and a source of vaccines. Laboratories for these are costly to establish for an individual country. Left to each nation to develop laboratories using its own resources, most countries would hesitate to do so. Such facilities are however almost invariably established and, usually for a limited period, operated with donor funds. Questions of cost-effectiveness are a rare consideration.

Table 3. Donor Projects Promoting Alternative Delivery of Veterinary Supplies and Services in Sub-saharan africa

CountryDonor(s)Main Focus
BurkinaFAOVillage poultry/small ruminant vaccinations
CARIDA/IFAD/ EEC/FAODrug distribution and herder training
CameroonIBRD/IFADDrug importation/distribution & vet practice
ChadGTZ/EEC/ IDA/ADB/FACVeterinary practice: vets and paravets
Cote d' IvoireCCCE/GTZVillage pharmacies and paravets
EthiopiaIDAParavets through service co-operatives
GuineaIDA/CCCE/ FACDrug inputs and veterinary practice
KenyaIDA/IFAD/ OPEC/EECVeterinary practice and cost recovery
MaliIDAParavets through herder associations
SenegalIDAParavets through herder associations
SomaliaIDA/GTZParavets and cost recovery
SudanIDAVeterinary practice
UgandaIDAVeterinary practice
ZaireIDA/FAC/ CIDAParavets through herder associations

Diagnostic Services

Epizootic Diseases: Many developing countries, large and small, have attempted to establish diagnostic laboratories for the major epizootic diseases, ie. rinderpest, FMD, Newcastle disease and pleuropneumonia of cattle and goats. However, only a few have been able to maintain them. Fortunately, with the encouragement and assistance of inter-national organizations, principally FAO, a few of the stronger national laboratories have assumed the role of regional diagnostic laboratories for the most important epizootic diseases.

A large proportion of the diagnostic work for FMD continues to be done in laboratories outside the developing countries because of what would appear to be non-technical reasons. In addition there have been moves over the past decade to standardize diagnostic reagents and techniques for epizootic as well as other important diseases. There are also continuing attempts to have, carefully positioned in various developing countries, truly international well equipped and staffed diagnostic laboratories.

These would be in addition to the existing regional collaborating laboratories which still remain the property of the host country.

Non-epidemic Viral and Bacterial Diseases: Confirmatory diagnosis of both viral and bacterial diseases remains a difficult problem where culturing and the production of reagents and use of more sophisticated techniques is required. At best such diagnostic work is done in centralized laboratories which results in considerable delays in obtaining results. Often laboratory reports are received long after the problem has passed.

More effective diagnostic services will require greater investment in research aimed at developing simple but highly specific field tests. These may employ standardized sera/monoclonal antibodies and corresponding antigens. Technology for their preparation exists and is becoming more accessible to developing countries. Their preparation however requires substantial investment in equipment and expendable supplies.

The establishment of regional diagnostic laboratories have been previously suggested by FAO. There is now a collaborative programme between FAO and OAU/IBAR to establish such a system. This will help in ensuring ready availability of standardized diagnostic reagents. A mechanism will however need to be developed to ensure that these are sustainable in the long run. Centralized mass production would help in reducing costs and therefore making them more affordable.

Sustainability must be an overriding consideration in running centralized laboratories for reagent production. For this reason ways have to be found to ensure a system of cost recovery. Alternatively, committed long term regional member country contributions to their operation will be required. Such commitments must include provision of a certain amount of foreign exchange allocation.

Diagnostic advances have an important bearing on tick-borne diseases control. Traditional diagnostic techniques using microscopy to examine blood, lymph node or brain smears are notoriously laborious and inaccurate. An important feature in current attempts to improve cost-effectiveness of tick-borne disease control is the development of highly precise diagnostic methods to ensure that the still expensive vaccines are employed only where indicated.

Vector-borne Protozoal/Rickettsial Diseases: Lack of sensitivity has been a serious drawback for the antigen detection techniques which have been traditionally used for Babesia, anaplasma, Theileria, Cowdria and trypanosome diagnosis. Both sensitivity and specificity have been greatly improved by new monoclonal antibody based antigen capture ELISA tests and DNA probes. For a number of these, diagnostic kits are already available for evaluation. These tests still depend on a considerable degree of sophistication and generally have to be done in central laboratories. They are useful for survey purposes but would probably not be cost-effective for routine use. Greater usefulness will require further simplification to make them directly applicable at the field level.


Because of understandable desire to ensure protection against epizootics, many governments in developing countries have established vaccine production laboratories. There are a number of alternatives which can be pursued to improve production efficiency which include the following:


As has been discussed, control of epizootic diseases through regional mass vaccination campaigns has been effective and has saved national herds from such diseases as rinderpest and CBPP. As long as these epizootics exist international efforts through governments would appear to be the only effective means of vaccine delivery. As these diseases are controlled, the maintenance of the immune status might devolve to national veterinary departments which would decide whether this can be done more cost effectively directly by them or through the emerging private practitioners via contract arrangements.

These decisions will only be possible if the veterinary profession as a whole and national veterinary departments in particular take greater interest in the application of economic principles. It is noteworthy that several African countries are considering the establishment of veterinary epidemiology and economics courses in their national universities and at least one has already instituted such a course. This is a trend which needs to be encouraged and supported.


In contrast with vaccines for which the developing countries now have a great deal of indigenous technology, the third world is almost completely dependent on the import of therapeutic drugs. In Sub-Saharan Africa, drug importations are carried out, with few exceptions, directly by government or government parastatals. This mechanism has been notorious for providing poor distribution and availability of veterinary drugs at the farm level. Farmer demand for effective drugs has frequently been met by smuggled drugs with all the attendant problems of lack of consistent supply, questionable handling practices, high cost and loss of government tax revenue. Despite these limitation, smuggled veterinary drugs in many countries have been the primary supply and distribution method.

“Revolving funds” for drug purchase and delivery are one method used to liberalize drug supply in numerous African countries. Overall return of funds ranges from 30 to 50 percent when operations are decentralized and collections are made through vaccination posts. The most successful scheme (for example, in the CAR), which returns 85 to 90 percent of expected funds, utilizes herder associations to collect the money and a double accounting system of accountability is used. Veterinary drug distribution through private pharmacies or farm supply/fertilizer outlets is used in Asian and Latin American countries. Drug availability seems to be better than in Africa. However prices may be exceedingly high due to the inherent high cost of small dose packaging and low turnover. Where veterinarians are actually seeing and diagnosing clinical disease and prescribing drugs for farmer's animals, turnover is faster. Additionally if veterinarians think in terms of “community epidemiology”, all at-risk animals receive treatment or preventive and consequently lower cost, multi-dose packaged drugs are stocked and prescribed. These two conditions, active delivery of clinical services and treatment of all at-risk animals, tend to reduce the per treatment cost, are generally more efficacious and are medically more sound.


Traditional Approaches

In many if not most developing countries, veterinary services were established to provide diagnostic and control services for unfamiliar tropical diseases which puzzled colonial settlers or to fight diseases introduced by them to new environments.

The number of veterinarians was for many decades low and a tradition was established to employ all of them within the government. This continued to be the case even after the major epizootic diseases were brought under reasonable control and the functions of veterinary departments became more diversified. The policy of guaranteed employment for all qualified graduates in these increasingly complex and diversified veterinary departments has been brought into question. The debate continues about which functions should be priority undertakings of the public sector and which should be left for management by the growing private sector of veterinarians.

Even with increasing numbers of veterinary graduates, and in some respects because of it, the delivery of veterinary services to the majority of livestock raisers is declining in many developing countries. The increasing employment of veterinarians in the government services over the last thirty years has outpaced the rate of increase of funds to run veterinary departments. As a consequence, the percent of funds devoted to non-salary operational costs (in absolute terms) has dropped by approximately one third in West African countries and by two-thirds in Kenya (Table 4). This situation points out the fallacy of relying on livestock unit:personnel ratios to plan the delivery of veterinary services. Even if ratios of 1000:1, or probably even 100:1, were achieved, veterinary services would not be effectively delivered if supplies, transportation and other in puts were not provided to facilitate the actual delivery of goods and services to the livestock.

Table 4. Main Contributor to Non-availability of Services

W. AFRICA' 606436
 ' 767525
KENYA' 744060
 ' 817030
 ' 898020

Government Management of Animal Health

Management of Notifiable Disease Control: There is little doubt that animal diseases with epizootic or zoonotic potential are of state interest and their control should be a public responsibility. This responsibility includes legal obligation for farmers/animal owners to report suspected disease occurrence to the government and for the veterinary authorities to give prompt confirmatory diagnosis as well as imposing such control measures as are appropriate for containing disease spread. Apart from vaccinations, controls could include quarantines or animal disposal.

There are legal penalties for non-compliance. While ultimate responsibility for enforcing the control of such diseases, clearly rests with the government veterinary authorities, there are measures that the state can take under certain conditions, which may improve cost-effectiveness. Such measures may include:

When combined with other measures, such as the withdrawal of unfair competition in clinical practice by government veterinarians, contracts of the type described above could be an incentive for veterinarians to become self-employed.

Veterinary Public Health Management: Management of abattoir functions including the assurance of humane slaughter of animals and meat inspection is governed by individual national legislation and generally is in accord with international zoosanitary codes.

This and other food inspection functions, depending on circum-stances obtaining in a given country, may be under veterinary control. Efficient management of these functions presents considerable problems because outside the large urban areas, which have centralized slaughtering and food processing facilities, rural facilities are scattered and difficult to police.

Here again, provision of these types of services could be based on cost recovery mechanisms in the form of user fees to butchers, meat markets and food processors. These fees would likely be passed on to the consuming public as a charge for their public health.


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