INTRODUCTION

Rinderpest is an acute, febrile, highly infectious, viral, killing disease of domestic livestock and wild animals characterized by pyrexia, necrosis of visible mucosal membrane and death. It has caused devastating stock losses in many parts of the world for centuries. Rinderpest virus belongs to the genus Morbillivirus of the family paramyoviridae, which strains vary considerably in their virulence. Among domestic livestock cattle, zebus and water buffaloes are the species principally affected. Rinderpest of sheep and goats occured on rare occasions. Numerous wild animal species showed severe disease and high morality. Among them belong African buffaloes, eland, kudu, wild-beest, various antelopes, bushpigs, warthog, giraffes, etc. Rinderpest is rare among camelidae.

Rinderpest occurred in many parts of Africa (Tab. 1), the Middle East, South and East Asia (Tab. 2). The distribution of rinderpest in Africa was much reduced by an international vaccination campaign that was carried out during 1962-1976. There was unfortunately a resurgence of the disease culminating during the first half of the 1980s. The rinderpest spread during relatively short period over African continent up to Israel in the North, Djibuti in the East, Senegal in the West and Zambia in the South. A similar pattern of rinderpest epizootics was also experienced in Asia in the 1980s when it spread from South Asia up to Turkey.

Most strains of rinderpest virus are highly contagious. Infection is usually spread by direct contact between animals. The virus is excreted in the expired air, nasal discharges, saliva, faeces and urine. The virus survives poorly in the environment. In enzootic areas the disease tends to spread slowly, affecting mainly younger animals, with flare-ups occurring when nomadic herds mingle at watering places or markets. The incubation period usually ranges from 3-9 days, but may be longer in cattle with a high innate resistance. The clinical syndrome varies from peracute to subacute. Laboratory diagnosis (8) consists in antigen detection using agar gel immunodiffusion test, direct and indirect immunoperoxidase test, counter immunoelectrophoresis and immunohistopathology. Other tests used are virusneutralization test, ELISA test and virus RNA detection by rinderpest specific cDNA probes and amplification by polymerase chain reaction (PCR).

Joint Campaign against Rinderpest in Africa (JP 15) started in 1961 (cost about 16 million US$) didn't achieve the aim of eradication. A decade after the end of this campaign reducing the diseases to some small remaining “pockets” of infection, the rinderpest started rapidly spreading again from virus residual territories throughout African continent. Only during 1980-1982 rinderpest outbreaks caused losses of USD 2 billion. FAO as technically supporting agency and the Organization of African Unity/Inter-African Bureau of Animal Resources (OAU/IBAR) as coordinating agency with financial assistance of the European Community started Pan African Rinderpest Campaign (PARC). The spread was blocked and the disease was significantly reduced to several relatively small "infected areas". Simultaneously was started West Asia Rinderpest Eradication Campaign (WAREC) and South Asia Rinderpest Eradication Campaign (SAREC). All these programmes were later merged into Global Rinderpest Eradication Programme (GREP) with the goal to achieve complete global eradication by the year 2010. It would be only the second disease eradicated in history, after small pox. FAO together with International Agency of Atomic Energy (IAEA) and other international organizations established special Rinderpest Laboratory networks in Africa, Middle East and Asia. Rinderpest vaccine production and its control was carried out by selected affected countries supported by FAO technical assistance.

MATERIAL AND METHODS

The main sources for this article were represented by the documents of the Food and Agriculture Organization of the United Nations (1,2,6), produced in particular by Animal Health Service (AGAH) responsible for international programmes against major diseases, including the rinderpest. Other sources of statistical data were represented by the global yearbooks such as FAO/WHO/OIE Animal Health Yearbook (4) and OIE World Animal Health (7). Very important were the reports of the expert consultations on rinderpest eradication campaign providing useful information on the methodology and programme against this plague (10). AGAH documents on rinderpest were produced by special unit EMPRES - Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases (3,5). Priority of this unit has been to organize global rinderpest eradication programme (GREP). Finally, personal experience of the author, as former Chief, AGAH responsible also for the global rinderpest eradication project and Chief-Editor of the FAO/WHO/OIE Animal Health Yearbook, was taken into consideration as well.

First part consists in analyzing official data on rinderpest occurrence in Africa and Asia as reported by the FAO and OIE member countries. These data were not always reliable and comprehensive due to the fact, that almost all affected countries suffered by lacking adequate national reporting system, necessary professional staff in terms of number and qualification, funds, diagnostic laboratories and other needed facilities, transport, logistic and support by the national and local authorities. Other reason was the fact that affected animals without specific clinical symptoms cannot by detected without special tests. The most frequent information was the answer if the rinderpest exists or not in the given countries. Practically all data about the number of outbreaks and affected animals were only a fragment of the reality. However, the data in spite of the underreporting, were providing basis for the orientation about specific epizootiological situation

Other part consists in analyzing the strategy and progress of rinderpest eradication international campaign in Africa and Asia beginning the year 1980 when started new phase of the rinderpest control. There were factors not favorable to the eradication such as difficulty in detecting the disease in wild susceptible species and the disease was occurring in areas relatively inaccessible because of natural barriers or situation of human origin (social unrest, civil wars, etc.). On the other hand following factors were favorable to the eradication such as: the virus is fragile and susceptible to environmental factors and disinfectants; the short incubation period, ease of spread and high mortality in fully susceptible animal enable early recognition of acute cases; animals that have recovered from the disease do not become virus carriers and have longtime immunity; transmission is almost always by direct contact between infected and susceptible animals. General principles of rinderpest control consisted in isolation or slaughtering of sick and in-contact animals (no treatment available), destruction of cadavers, disinfection and protection of free zones. For specific immunization were used highly effective cell-culture attenuated vaccines; immunity lasts at least 5 years and probably is life-long (8).

STRATEGY AND RESULTS

Following methods for dealing with a rinderpest disease emergency were considered and used according to particular epizootiological situation and local conditions: stamping out by slaughter; elimination by modified stamping out with ring vaccination and quarantine with ring vaccination without slaughter.

Stamping out by slaughter was preferred option in: introduction of rinderpest in an area within rinderpest-free country; countries with efficient veterinary services and functioning disease information and reporting network, including laboratory diagnostic support and surveillance to prevent reintroduction of rinderpest; countries with sufficiently contingency funds for immediate compensation of affected farmers and countries where there was no religious, cultural or ethnic objection to the slaughter of susceptible livestock species such as cattle. The essential elements of stamping out method included: slaughter of clinically affected, suspected and exposed susceptible animals in the affected herds/premises/settlements within the infected zone; safe disposal of carcasses; decontamination; quarantine and movement restriction; tracing and surveillance; awareness campaigns; restocking at least 30 days after cleaning and disinfection.

Modified stamping out with ring vaccination was preferred for: countries where there were doubts about maintaining strict quarantine or animal movement control; countries where there were inadequate resources for comprehensive disease surveillance and countries that did not possess the financial resources needed for complete stamping out. The essential elements of modified stamping out method: slaughter of clinically affected animals and suspects in the infected herds/premises; immediate ring vaccination and identification of vaccinates; quarantine and movement control; tracing and surveillance to determine the source and extent of infection; an awareness campaign to promote the cooperation of livestock owners and the general public; proof of elimination; eventual slaughter of affected animals, if this is realistic for export trade purposes.

Quarantine and ring vaccination without slaughter was preferred in countries where: slaughter of animas, e-g- cattle, was either forbidden or unacceptable to the community and there were inadequate resources for stamping out or modified stamping out. The essential elements of quarantine and ring vaccination method: immediate quarantine and movement control in the infected zone; ring vaccination and identification of vaccinates; disposal of carcasses of dead animals and decontamination; tracing and surveillance to determine source and extent of the infection; awareness campaign; proof of elimination.

Conditions for declaring any former affected country as rinderpest-free were identified by the OIE International Animal Health Code (9). Before declaration that the country as a whole is rinderpest infection free, it must pass the period of provisional freedom from disease (i.e. clinical cases) and then the period of freedom from infection, which takes several years of intensive surveillance and laboratory testing to prove the given status.

Achievements: The global rinderpest eradication programme has achieved considerable results reducing its territorial distribution by the end of 2002 to northeast Kenya and southern Somalia only. Experts are increasingly confident that the virus responsible for the devastating livestock disease rinderpest is not longer present in three of its last reserves, in Sudan, Yemen and Pakistan. The mass vaccination of a million cattle in south-eastern Sudan between May 2001 and May 2002 has contributed to growing confidence that the virus has finally been eliminated in that country In Asia, the last reported outbreak of rinderpest was in Sindh Province, Pakistan in October 2000.

DISCUSSION AND CONCLUSION

Global rinderpest eradication campaign represents the most extensive international programme controlling an animal disease in the history. An intense international effort must now focus on the Somali pastoral ecosystem of northeast Kenya and southern Somalia before the virus breaks out of its last stronghold through the movement of nomadic herds or the export of cattle. Thanks to very comprehensive action, based upon system approach supported by thousands of international and national specialists and other participants of respective countries as well as financially by relevant international organizations and donor countries, the eradication is already behind the door.

Eliminating rinderpest from the world will help to improve food security and the livelihood of the rural population of many developing countries. In this sense, the battle against rinderpest is also the fight against poverty.

REFERENCES

1. FAO (1996): The world without rinderpest. FAO Animal Production and Health Paper 129, Rome, 173 pp.

2. FAO (1996): Manual on the diagnosis of rinderpest, Rome

3. FAO (1998): Rinderpest: The challenge ahead. FAO Technical Consultation on the global rinderpest eradication programme. Rome, 201 pp.

4. Kouba, V. (Editor): FAO/WHO/OIE Animal Health Yearbook, Rome, 1980-1990

5. Masiga, W.N. (1999): Pan-African surveillance for transboundary animal diseases: The Pan-African programme for the control of epizootics, “PACE”. In: Fourth Expert Consultation on Emergency Prevention System for Transboundary Animal and Plant Pests and Diseases (EMPRES) – Livestock Programme, Rome, 128-130.

6. Obi, T.U., Roeder, P.L., Geering W.A. (1999): Manual on the preparation of rinderpest contingency plans, FAO, 34 pp.

7. OIE (1990-2002): World Animal Health, Paris

8. OIE (2000): Manual of Standards for Diagnostic Tests and Vaccines, Fourth Edition, Paris, 957 pp.

9. OIE (2003). International Animal Health Code, Paris, 510 pp

10. Rweyemamu, M. (1996): The global rinderpest status in 1996. In: Proceedings of the FAO Technical Consultation on the Global Rinderpest Eradication Programme, Rome, 41-48.

Corresponding author:

Prof. MVDr. Václav KOUBA, DrSc.

P.B. 516, 170 00 Praha 7, Czech Republic

Tab. 1 - Rinderpest occurrence and eradication in Africa, 1980-2000, as reported by individual countries

(included only countries with rinderpest occurrence during this period)

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COUNTRY	1 9 8 0	1 9 8 5	1 9 9 0	1 9 9 5	2 0 0 0	LAST CASE

Benin	+	+				?
Burkina Faso		+				1988
Cameroon						1986
Cote d’Ivoire		+				1986
Djibuti	+		+			?
Egypt		+				1987
Eritrea						1995
Ethiopia	+	+		+		?
Ghana						1988
Kenya	+	+	+	+		2002 ?
Mali		+				1986
Mauritania	+	+				?
Niger	+	+				1985
Nigeria	+	+				1987
Sudan	+	+				1991
Tanzania		+				1997
Togo						1986
Uganda	+		+	+		1994
Upper Volta	+					?

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Sources: FAO/WHO/OIE Animal Health Yearbook and OIE World Animal Health

Tab. 2 - Rinderpest occurrence and eradication in Asia, 1980-2000, as reported by individual countries

(included only countries with rinderpest occurrence during this period)

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COUNTRY	1 9 8 0	1 9 8 5	1 9 9 0	1 9 9 5	2 0 0 0	LAST CASE

Bahrain		+				?
India	+	+				1995
Iran						1994
Israel						1983
Kuwait	+					1985
Lebanon		+				1982
Mongolia						1992
Nepal	+	+				1990
Oman						1995
Pakistan					+	2000
Russia						1998
Quatar						1987
Sri Lanka						1994
Turkey						1996
Yemen	+	+				1995

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