2.1 ECF IMMUNIZATION PROGRAMMES ON PRIVATE FARMS
2.2 ESTABLISHING A CENTRAL DEPOT FOR VACCINE DELIVERY
2.3 ESTABLISHING A NATIONAL TEAM FOR VACCINE DELIVERY
DANIDA - Danish International Development Agency
DVS - Department of Veterinary Services
EAVRO - East African Veterinary Research Organization
ECF - East Coast Fever
ELISA - Enzyme Linked Immunosorbent Assay
IFAT - Indirect Immunofluorescent Antibody Test
ILRI - International Livestock Research Institute
ITM - Infection and Treatment Method
LIRI - Livestock Health Research Institute
NARO - National Agricultural Research Organization
NPC - National Project Coordinator
PI - Post-immunization
TBD - Tick-borne Disease
UNDP - United Nations Development Programme
The countries of East, Central and Southern Africa have been searching for an economically viable way to control ticks and tick-borne diseases (TBDs) in cattle since the beginning of the century. As higher-producing exotic cattle breeds were introduced, the need to reduce the negative impact of ticks and TBDs dramatically increased. For countries in which East Coast fever (ECF) was present, improving ECF control strategies became a research priority. Until the early 1980s , however, ECF was controlled exclusively by the intensive application of acaricides. Two major developments then occurred that changed the approach to ECF control: the development of chemotherapeutic agents which could actually treat ECF and improvements in the infection and treatment method (ITM) for ECF immunization.
An integrated approach to tick and tick-borne disease control in the region was developed, advocating ECF immunization coupled with reduced tick control and the use of therapeutic drugs, as required, to treat ECF. Although ITM was not perfect, it was the only immunization method available and provided good protection against ECF, reducing the need for expensive acaricides and therapeutic treatment. By the late 1980s, interest in the method had dramatically increased, leading to donor support of ECF immunization in the region. Several projects were initiated with the principal objective of evaluating ITM technology for its ability to control ECF. Through donor support, FAO established a Tick-borne Disease Vaccine Production Centre in Malawi with the aim of producing an ECF vaccine that could be used by the entire region.
By the early 1990s, ECF immunization was being evaluated by several countries in the region. However, since the procedure required more technical expertise and post-immunization monitoring, its cost was higher than that of conventional vaccines and its use was generally restricted to improved cattle, which require more protection from ECF. Based on the positive results of immunization studies conducted in several different countries of the region, it was proposed to offer ECF immunization to private farmers raising improved cattle (exotics and cross-bred cattle). Most countries involved are now attempting to establish long-term, self-sustainable ECF vaccine delivery services in order to help cattle farmers establish a more economical way to control ECF.
Of the estimated 4.5 million cattle in Uganda, approximately 240 000 are improved dairy cattle and 195 000 improved beef cattle. A major emphasis within the livestock sub-sector is to increase dairy production by introducing higher-producing exotic cattle breeds and the numbers of improved dairy cattle should sharply increase over the next several years. After nutrition, ECF is the largest limiting factor for the economic management of improved cattle, having the largest negative impact on the Bos taurus dairy breeds. The result is high management costs and high mortality rates for improved cattle, which greatly limits the success of cattle improvement efforts.
Uganda took part in ITM evaluations for ECF control in the early 1970s, in collaboration with the East African Veterinary Research Organization (EAVRO, Muguga, Kenya). These indicated that ITM provided good protection against ECF disease. Ugandan involvement with ECF immunization was then suspended until the early 1990s, when Uganda joined the FAO Regional Tick and TBD Control Programme, with donor support from various Governments (Denmark, Netherlands and Belgium) and the United Nations Development Programme (UNDP).
Project GCP/UGA/027/DEN, "Immunization Against East Coast Fever in Cross-bred Cattle in Uganda" was conducted in Uganda from April 1990 to August 1993. Its main objective was to assess the protection provided by the ECF trivalent vaccine produced in Malawi ("Muguga cocktail") under Ugandan field conditions. Three trials were conducted in different areas of the country (Lusenke, Mbarara and Sironkho) to evaluate the vaccine. The results indicated that the "Muguga cocktail" was a safe and effective vaccine that could be used in Uganda to control ECF in improved cattle. The project proposed that ECF immunization using the trivalent vaccine be made available to private farms in an attempt to reduce the incidence of ECF while improving the economics of tick control. The recommendations of the project led to the development of the current GCP/UGA/030/DEN "Integrated Tick and Tick-borne Disease Control Project".
A regional project document for "A Coordinated Multi-donor Programme for Integrated Tick and Tick-borne Disease Control in Eastern, Central and Southern Africa" was prepared by FAO staff members, consultants and representatives of participating national Governments in March 1993. It proposed several projects for the region including support for the regional vaccine production laboratory in Malawi, a regional coordination project and several national projects with emphasis on ECF vaccine delivery to private farms. A project document proposal for Uganda was prepared with a total donor budget of $US 1.26 million. It was planned to start in mid-1993 and had a scheduled duration of two and a half years.
Project implementation finally began in May 1994 after a one year delay. It initially had a budget for eight months or to the end of 1994 and there was no official project document. Project staff prepared an initial work plan to cover 1994, based on the March 1993 project proposal for Uganda. In early 1995, Ugandan government authorities decided that the project was not ready to deliver the ECF vaccine to private farms and proposed further research on government farms prior to further immunization on private farms. Following discussions with FAO technical staff, the Government finally agreed to permit immunization on private farms. Project staff developed an acceptable work plan to cover 1995. The project was later extended to cover 1996 and ultimately to 30 June 1997. The project was finally implemented for a full three-year period without a project document. Although the project duration was extended by six months, the total budget remained unchanged at $US 1 267 136.
The Ugandan Government contributed national personnel from the Livestock Health Research Institute (LIRI) of the National Agricultural Research Organization (NARO) and the Department of Veterinary Services (DVS). The DVS provided office space, laboratory facilities and a building to serve as project depot at the Veterinary Epidemiology and Diagnostic Laboratory in Entebbe. A government counterpart fund amounting to $US 425 050 was made available to the project to facilitate project field activities.
The "Integrated Tick and Tick-borne Disease Control Project" for Uganda was financed by the Danish International Development Agency (DANIDA), executed through FAO and implemented by the Ministry of Agriculture, Animal Industry and Fisheries.
The development objectives were to increase livestock production for local consumption, thus reducing the importation of meat and milk and enhancing the possibilities of establishing exports, to provide additional income for livestock owners through the sale of surplus, which could eventually improve the protein diet of the urban poor, to reduce the overall regional level of potential environmental contamination with acaricides (including the level of residues in animal products) and to decrease land degradation through improved livestock management systems.
The main objective was to assist Ugandan livestock farmers to establish more economically viable tick and TBD control strategies for improved cattle. All project activities were directed at the establishment of a self-sustainable ECF vaccine delivery service for Uganda. This service would fulfil a number of requirements. It would introduce ECF immunization to target private farmers through ECF immunization demonstrations and cost-sharing programmes. It would prepare a central depot for the importation, storage and distribution of TBD vaccines and other required immunization inputs. It would establish a national team within the Government to assist with providing technical support, laboratory assistance and general information to the veterinary field personnel conducting TBD immunization and cattle farmers. It would provide the training and extension required to establish TBD vaccine delivery at the district level. It would be responsible for the collection of information and the technical evaluation of the ITM as an alternative approach for ECF control. It would register the ECF vaccine and other TBD vaccines, if necessary, prior to establishing full cost-recovery for vaccine delivery. It would evaluate the various cattle farming systems in Uganda to establish requirements for improving the economics of tick and TBD control. Finally, it would procure the equipment and materials needed to support laboratory improvement, training, extension and vaccine delivery.
The project prepared a comprehensive technical document (FAO field document dated September 1996) thoroughly covering all project field activities from August 1994 to June 1996. After the preparation of this field document, the project continued by providing initial ECF immunization demonstrations for Kiboga, Hoima and Luwero districts. In addition, Mubende district conducted three cost-sharing programmes.
A total of 27 immunization programmes was provided by the project, involving 163 different farms from 13 districts of the country. A total of 2 157 head of improved cattle was immunized against ECF while 19 veterinarians and 8 animal health officers received training in ECF vaccine delivery. These immunization programmes had three broad objectives: to train Ugandan veterinary field staff in ECF vaccine delivery; to demonstrate ECF immunization to the beneficiary group of Ugandan cattle farmers; and to collect the field data required to evaluate the ITM for its potential in the improved control of ECF disease on private farms in Uganda.
Several aspects of the trivalent vaccine and the ITM required assessment. Post-immunization (PI) reactions were evaluated for each immunized animal. This provided the following results: no reactions: 74%; mild reactions: 17%; moderate reactions: 6%; and severe reactions: 3%, yielding a safety factor of 91%. Post-immunization monitoring was required to assist the remaining 9%.
Approximately 8% of all immunized cattle required post-immunization treatment: 5% of cattle received PI oxytetracycline in an attempt to reduce non-specific fevers, while 3% of cattle developed clinical signs of ECF disease requiring antitheilerial medications.
Three deaths followed immunization. However, other factors such as concurrent disease, stress, or judgemental errors relating to the use of therapy could have contributed to these deaths.
Elevated temperatures, clinical illness and required treatments occurred between days 8 and 29 PI. The vast majority of problems occurred between days 11 and 22 PI. This is regarded as the critical period, when reactions may occur and PI monitoring should be emphasized.
The project collected sera from all immunized cattle on the day of immunization (day 0) and 35 days after immunization (day 35). Sera samples were evaluated for the presence of antibodies against T. parva schizonts using the Indirect Immunofluorescent Antibody Test (IFAT) at a dilution of 1:640. An average of 36% of all cattle was positive on day 0, indicating a moderate level of exposure to T. parva prior to ECF immunization. For individual farms, day 0 serology had a range of 0% to 73% positive. At day 35 PI, an average of 86% of all cattle was positive for T. parva schizont antibodies (range of 69% to 100%). True sero-conversion (day 35-day 0) was 50%, while provided or stimulated immunity (day 35) was 86% (indicating good herd immunity).
Owing to the relatively high percentage of improved cattle having evidence of field exposure to T. parva prior to ECF immunization (36%), emphasis should be placed on the immunization of young calves in an attempt to provide ECF immunity before contact with infected ticks.
Post-immunization monitoring is required to control vaccine reactions in 9% of immunized cattle. During immunization programmes, the project and participating district veterinary staff provided a moderate level of monitoring, usually visiting each farm six times during the PI monitoring period. On average, it costs about 3 500 Uganda Shillings ($US 3.5) for each immunized animal to receive this level of monitoring support.
In order to establish economical vaccine delivery services for Uganda, post-immunization monitoring costs must be reduced by decreasing the number of farm visits made by the veterinarian and increasing the farmers' responsibility for monitoring immunized cattle.
Following ECF immunization for a particular cattle herd, tick control should be reduced to decrease tick control costs (acaricides, labour, infrastructure, etc.) and also to allow for limited T. parva transmission between the tick vector and the bovine host. This will provide further immune stimulation through natural exposure to ECF.
Since the amount of tick control relaxation depends on several factors, each farm will have to develop a reduced tick control strategy based on its specific conditions.
The project assisted four farms in Mubende district to establish relaxed tick control following ECF immunization. It was decided that tick control could be reduced by 50-60% once ECF disease was brought under control by appropriate immunization.
A reduction in tick control costs is one of the major benefits from the adoption of ECF immunizations. However, tick control relaxation should be established gradually and under veterinary supervision. More information is required on this subject.
Integrated tick and TBD control means that other TBDs and their respective vector ticks must also be considered.
The project provided serological evaluations of calves from improved dairy herds under intensive or semi-intensive tick control in an attempt to increase understanding of Anaplasmosis and Babesiosis transmission. Tick control on these farms had dramatically reduced the Boophilus tick population, resulting in very low exposure of calves to these two TBDs.
At present, it is impossible to provide accurate serology for the determination of exposure to C. ruminantium. It is a highly acute disease and also difficult to confirm from normal laboratory samples, which makes accurate diagnosis very difficult. As a result, the project has minimal information on Cowdriosis in Uganda.
Due to intensive tick control aimed at controlling Rhipicephalus appendiculatus (vector tick for T. parva), the exposure of calves to Anaplasma and Babesia is minimal. Because of this, adult cattle are highly susceptible to these two diseases.
If tick control relaxation following ECF immunization allows an increase in Boophilus ticks and exposure to Anaplasmosis and Babesiosis in adult cattle, immunization to provide additional protection from these two diseases should be considered.
The presence of Cowdriosis is the largest obstacle to tick control relaxation. Live vaccines are available to help control this disease but should only be considered when optimal veterinary supervision can be provided to control PI reactions. A much better understanding of the epidemiology of Cowdriosis is required.
The project was able to establish cost-sharing programmes in two districts. A total of nine cost-sharing programmes was conducted in Mubende district (6) and Mukono district (3). Farmers paid U Sh 5 000 for each immunization. During these cost-sharing programmes, the project calculated the costs for all immunization inputs.
The delivery cost of ECF vaccine varied from a low of U Sh 8 597 to U Sh 15 966. This was determined by several variable factors concerning the overall delivery process. It is important to note that post-immunization monitoring was responsible for one-third of the total delivery cost.
The ECF vaccine can be delivered to the private farm for a reasonable and economical price. However, an acceptable reduction in the PI monitoring provided by the veterinarian is required to reduce the overall vaccine delivery cost.
It is obvious that the ECF trivalent vaccine provides good protection against ECF disease for improved cattle. It can be delivered to private farms safely, effectively and economically. Tick control following ECF immunization can be relaxed to provide enormous economic benefits for the farmers. Other TBDs need to be examined and their respective vaccines should be advocated when justifiable. Farmer interest is apparent, as has been demonstrated by their willingness to participate in cost-sharing programmes, and farmer demand for the vaccine is increasing. Vaccine delivery has become the critical issue for the continuation of this project.
The project has established a central depot for the storage and management of all vaccine delivery inputs. In 1996, a building at the veterinary Epidemiology and Diagnostic Laboratory in Entebbe was repaired to provide adequate storage space. This building was doubled in size to furnish the project with office space for depot management. By October 1996 the project had a fully functional depot to support field delivery of TBD vaccines. The project also established an appropriate cold chain to support laboratory requirements and vaccine field delivery (laboratory refrigerators/freezers, ultra-low freezer, liquid nitrogen containers and field cold-boxes).
The Government's principal responsibility concerning vaccine delivery should be as an advisory body to provide veterinarians and farmers with current information through training and extension. A national team is required to assist with the development of vaccine delivery services and to provide back-up laboratory support for TBD diagnosis and to monitor various aspects of vaccine delivery.
A National Project Coordinator (NPC) was provided by LIRI. The project provided training to prepare the NPC, who is now able to offer training for field veterinarians, extension to farmers, assistance for the establishment of vaccine field delivery, laboratory support and general project management. The project supplied and supported all required logistical inputs for the NPC.
The project emphasized the need to develop a well-equipped modern laboratory to provide assistance for the diagnosis of TBDs and other pathogens, as well as the monitoring of ECF field immunization. The laboratory was dramatically upgraded by the procurement and installation of the equipment required for standard light microscopy including oil immersion, fluorescent microscopy for the IFAT and ELISA test serology for TBD diagnosis.
Laboratory staff, composed of two laboratory technicians and two laboratory assistants, received appropriate training through the project and other funding sources.
An NPC was trained and the TBD diagnostic laboratory in Entebbe improved. As a result, the Government is now in a position to assist and support TBD vaccine delivery.
Training and extension were project priorities. The project's NPC, a veterinary officer from Mubende district and the project's senior laboratory technicians benefited from study tours organized and supported by the project.
The NPC attended several workshops and conferences in order to acquire up-to-date information concerning all aspects of integrated tick and TBD control.
Project staff organized and implemented seven training programmes for the introduction of the integrated tick and TBD control strategy to veterinary field staff at the district level.
The project's laboratory technicians organized two training programmes in Entebbe for district laboratory staff and other laboratory personnel from the Entebbe laboratory. These programmes provided training in the preparation of laboratory samples, techniques for the diagnosis of vector-borne diseases and basic serology used in TBD surveillance.
The project provided a consultant from the International Livestock Research Institute (ILRI), Kenya, to install and standardize the new Enzyme Linked Immunosorbent Assay (ELISA) equipment for TBD diagnosis. During this consultancy, project laboratory staff were trained in the ELISA technique and the operation of the ELISA equipment.
Project activities included extension to farmers through general farmers' meetings at district level, farm visits, the completion of farmer questionnaires and ECF immunization demonstrations on private farms. As an introduction to the subject of ECF immunizations for improved cattle; a general farmers' meeting was organized for each district prior to immunization demonstrations. Thirteen meetings were organized, with 454 total participating farmers.
An essential step for the development of long-term, self-sustainable ECF vaccine delivery services is the official acceptance of the vaccine by the Government. The project considered vaccine registration a priority in facilitating the acceptance of this vaccine by veterinarians and farmers, and the essential factor in making vaccine delivery the responsibility of the private sector.
The project prepared the "Application Form for Registration of a Drug for Veterinary Use" (application form, five appendices and 308 pages of 13 supporting attachments) for the ECF trivalent vaccine on behalf of the Department of Veterinary Services. This registration application was to be submitted to the National Drug Authority by 15 August 1996. Although it was finalized and transmitted to the Commissioner of Veterinary Services for his signature on 8 August 1996, the application has never been officially submitted to the National Drug Authority for official registration.
For various reasons, the Government does not have enough confidence in the ECF trivalent vaccine to propose its official registration. This situation has created considerable confusion in the execution of a project based on ECF immunization using the trivalent vaccine.
Throughout the project, the procurement of necessary equipment and materials continued to support all activities. This equipment was required to support laboratory improvement, vaccine delivery and training and extension activities. It should be noted that the three-year project budget included extra funds for the purchase of materials required to establish large-scale ECF vaccine delivery. Since the project was slow to develop vaccine delivery, these funds were not required. They will be returned to the donor (DANIDA) and listed as project savings.
Project procurement adequately supported all project activities. The equipment and materials purchased by the project will enable the Government to continue activities involving integrated tick and TBD control as the project enters the next phase.
Apart from a self-sustainable system of vaccine delivery, all other requirements for ECF vaccine delivery were established. The development of sustainable vaccine delivery services at the district level is a priority for project continuation.
The following recommendations are essential for the continuation or acceleration of ECF vaccine delivery.
The Uganda veterinary profession and, more specifically, veterinarians involved with government policy must make decisions concerning the future use of the ECF trivalent vaccine in Uganda. If it is decided that the ECF trivalent vaccine should be delivered to private farms by private veterinarians, the registration application for the vaccine should be submitted to the National Drug Authority for official government registration.
A project steering committee should be established to provide valuable inputs during project preparation and execution, and veterinary officers from the Department of Veterinary Services should be assigned to the project in order to assist the NPC while being trained in ECF vaccine delivery.
The continuation of project activities should be based on an official project document signed by all participants (Government, donor, etc.).
The project should continue to support a regional approach for the establishment of ECF vaccine delivery for the entire region affected by ECF disease. This regional approach includes a regional laboratory for vaccine production and a regional coordination unit.
ECF vaccine delivery services using the trivalent vaccine (Muguga cocktail) should be established at district level (based on government acceptance and support).
The project must seriously explore options involving ECF vaccine delivery, while accepting that the only long-term solution to vaccine delivery will be through the private veterinary sector.
ECF vaccine delivery should continue on a cost-sharing basis while farmers' interest is being developed through appropriate extension activities. Total cost-recovery must be the final goal of the field delivery project.
The project must consider how the immunization inputs and project depot will be managed in both the immediate future and the long term if vaccine delivery continues. This responsibility must be transferred to a private partner (veterinary drug company) or a specific interest group such as the Uganda National Farmers Association or UVA.
The project should cut vaccine delivery costs, including the reduction of PI monitoring by field veterinarians.
Project continuation should support various areas of research, such as: PI tick control requirements; cost/benefit or impact assessment concerning the ITM; requirements for other TBD vaccines; epidemiology of Cowdriosis; and socio-economic aspects of the ITM.
The project should collaborate closely with national research institutions (NARO/LIRI and Makerere University) for the implementation of various research activities.
The TBD diagnostic laboratory in Entebbe should be made available to assist other projects and activities requiring assistance with TBD diagnosis and sero-surveillance. Laboratory personnel should be provided with additional training to improve their understanding of ELISA serology techniques and district laboratories should be assisted so that they can provide better TBD diagnosis at district level.
The national team should continue with training and extension activities in an effort to promote integrated tick and TBD control in Uganda.
PROJECT STAFF
Dates of Service
Name Function Starting Date Concluding Date
International
M.C. Moran Chief Technical Adviser May 1994 June 1997
R. Nassimbwa Secretary May 1994 April 1995
M. Tuhumwire Administrative Assistant May 1995 June 1997
T. Lubega Driver May 1994 June 1997
National
C. Otim National Project Coordinator May 1994 Sept. 1994
R Nsubuga-Mutaka Research Officer May 1994 Sept. 1994
National Project Coordinator Oct. 1994 June 1997
M. Kakaire Research Officer May 1994 Dec. 1994
S. Erima Laboratory Technician May 1994 June 1997
S. Ongyera Laboratory Technician May 1994 June 1997
H. Lule Laboratory Assistant May 1994 June 1997
R. Dwoka Laboratory Assistant May 1994 June 1997
J. Okoboi Driver May 1994 Feb. 1997
E. Mubiru Driver March 1997 June 1997
STUDY TOURS
Participants Study Place Date
S. Ongyera Microscopic and TBD Vaccine 10 Sept.-14 Oct. 1994
serological diagnosis Production Centre,
of tick-borne diseases Malawi
R.C. Nsubuga- Visits to ECF vaccine Tanzania, Kenya 12 Oct.-9 Nov. 1996
Mutaka delivery projects
K. Mugabi Visits to ECF vaccine Tanzania, Kenya 12 Oct.-9 Nov. 1996
delivery projects
S. Erima ELISA technique for Zimbabwe 24 Nov.-8 Dec. 1996
tick-borne disease
diagnosis
MAJOR ITEMS OF EQUIPMENT PROVIDED
Cost
Quantity Item ($ US)
1 Toyota Hilux, 4 X 4 Double Cabin 17 000
1 Toyota Land Cruiser, 4 x 4 Station Wagon 25 000
1 Binocular microscope, Zeiss Standard 25 500
1 Binocular fluorescent microscope, Leitz 13 000
1 Magnetic stirrer/hot plate, Thomas 500
1 Shaker, microtiter plates, Jurgens 600
1 Centrifuge, Labofuge 200, Jurgens 1 000
1 Waterbath, Isotemp, Fisher 600
1 Balance, laboratory PT1200, Thomas 600
1 Shaker, Super Mixer, Thomas 300
1 Oven, 25 EG, Thomas 700
1 Incubator, 5EG, Thomas 900
1 Incubator/shaker, IS - 89, INSEL 2 500
1 Immunoskan, ELISA reader, BDSL 8 000
1 Water distiller, 3.8 LPH, Thomas 3 000
1 Laboratory pump, 30L./min., Bioblock 1 100
2 Multistepper dispenser/pipettor, 8-channel 1 600
2 ImmunoWash 12/ELISA 1 400
1 pH meter, CD740, Jencons 700
1 Balance, Ohaus/GT series, VWR 2 000
1 Centrifuge, refrigerated MP4R, VWR 7 200
1 Liquid nitrogen container, 35 HC 1 300
1 Liquid nitrogen container, 34 XT 1 200
1 Liquid nitrogen container, 18 XT 1 000
2 Liquid nitrogen container, 10 XT 2 200
7 Liquid nitrogen container, 3 XTL 5 000
1 Refrigerator/freezer, Ocean FG 34 1 200
1 Refrigerator/freezer, Ocean CBC 1 100
1 Deep freezer chest, ultra low temperature, Heraeus 9 000
2 Lab/field chest 300, Jencons 700
1 Computer, Olivetti 44C Notebook 3 000
1 Printer, HP LaserJet 4L 900
1 Printer, HP Deskjet 320 500
1 Overhead projector, A+K Portable 350 800
Cost
Quantity Item ($US)
1 Slide projector, ELMO 253 800
1 Screen, Sasco 60 inch 200
1 Camera, Olympus Super-Zoom 120 400
1 Generator, Honda Portable 2500XR 1 500
DOCUMENTS PREPARED DURING THE PROJECT
East Coast Fever Immunizations on Private Farms in Uganda. M.C. Moran and R.C. Nsubuga-Mutaka. Field Document.