Keynote paper
The keynote address entitled “Morbilliviruses into the 21st Century” was presented by Dr Tom Barrett, a molecular virologist conducting research on morbilliviruses at the Institute for Animal Health, Pirbright Laboratory, UK which hosts the FAO World Reference Laboratory for Rinderpest (WRLR). The paper reviewed the biology of the labile morbillivirus group illustrating the phylogeny of the viruses which have caused, and continue to cause, destructive epidemics of disease in both domesticated and wild animals as well as man. The molecular analysis of rinderpest virus has grouped recent strains into three lineages, one Asian and two African. One of the African lineages has been responsible for wildlife disease in Kenya recently and outbreaks in cattle and wildlife in East Africa. 30 years ago. These techniques provide a valuable insight into the movement of these viruses in and between animal populations and also offer improved diagnostic techniques and the prospect of novel vaccines. The most recent development reported was the ability to “rescue” infectious rinderpest virus from non-infectious material containing RNA.
Discussion
The paper stimulated much discussion concerning the source and epidemiology of the Kenya wildlife rinderpest virus. The possibility of the source being a cryptic persisting wildlife reservoir was dismissed on the grounds that the evolution of the disease in wildlife possessed all the characteristics of a virgin epidemic causing high mortality and this was supported by serological investigations. Despite the virulent nature of this virus in Cape Buffaloes and Lesser Kudus in particular, transmission experiments at the Muguga Laboratory, Kenya, had demonstrated only low virulence for cattle. The possibility of a transmissible non-revertant engineered rinderpest vaccine stimulated additional discussion.
Session 1: The distribution and nature of rinderpest
The session started with an overview of rinderpest occurrence from a global viewpoint based on epidemiological analysis by EMPRES, with the benefit of molecular epidemiological studies conducted by the WRLR. From this it was seen that rinderpest is now mainly limited in distribution to a small number of relatively well defined foci of endemic persistence although a cautionary note was sounded by indicating that the source of the 1991–93 rinderpest outbreaks on the Russian/Mongolian border, remote from any known persisting focus of infection, had never been determined and that this could possibly indicate an undisclosed area of rinderpest activity in central Asia. Subsequent papers dealt specifically with the regions involved in the GREP.
Dr Masiga (OAU/IBAR) reported that activities in Africa coordinated by the Pan-African Rinderpest Campaign (PARC) have limited the occurrence of rinderpest to fairly well defined foci in eastern Africa. Most West African countries have committed themselves to ceasing vaccination and declaring provisional freedom from rinderpest disease in the next year. Definition of the areas of uncertain status is proceeding with increasing momentum and this should provide a sound basis for eradication from northern Kenya/southern Somalia. The well described focus in northern Ethiopia is now yielding to intensive control efforts and the country is confidently expected to be free from rinderpest in the near future except for extensions from persisting foci in neighbouring countries. Despite major logistical problems the control activities coordinated by Operation Lifeline Sudan have proved effective and give hope for eventual eradication of rinderpest from southern Sudan.
Outside Africa, the status of the regions was described by Drs Rajan (India), Raja (Pakistan) and Kiani (IR of Iran). This varied from largely uncontrolled disease and limited epidemiological perception in Pakistan, through the uncertain status of the Northern Governorates of Iraq and neighbouring areas of Turkey, to the rapidly declining incidence of rinderpest in India, now restricted to a small area of the south. India's remarkable improvement in status has enabled zonal declarations of provisional freedom from rinderpest disease for the majority of the states. The status of Sri Lanka is uncertain although the last recognised outbreak was in 1994.
Overall, with the notable exception of Pakistan, where rinderpest is widespread and from which it has now spread to Khost and Phaktia Districts of Afghanistan, the picture was of increasingly restricted geographical occurrence and improving epidemiological definition. The prospect of imminent EC support for rinderpest control in Pakistan, within a project aimed at strengthening veterinary services and as part of a coordinated South Asia Rinderpest Eradication Campaign, was seen as an important advance. The need for improved disease intelligence from Central Asia was stressed although there was no evidence for disease persistence there.
Dr Rossiter's (EC/FAO Kenya) paper on epidemiological and clinical features of rinderpest in the 1990s indicated that all of the basic patterns of disease, including epidemic cattle plague, wildlife epidemics and mild disease in cattle, had occurred in recent years just as they had in the past and this was also true of the marked ocular lesions seen in Lesser Kudus in Kenya. His paper posed many questions concerning the determinants of endemicity but concluded that the tendency for some observations to fall outside predicted classical patterns should not prevent eradication.
Discussion
Dr. Raja (Pakistan) confirmed the widespread occurrence of rinderpest in Pakistan and suggested that, in Sindh state, the disease was not restricted to the dairy colonies which supply milk to Karachi. There was also concern that the recent epidemic in the Northern Areas had not been eliminated and that sporadic outbreaks were occurring in the rest of the country. Associated causes for concern are the known invasion of Afghanistan from Pakistan in 1995 and the rapid motorised transport of cattle from Pakistan. This clearly increases the risk of rinderpest introduction to many countries.
Several participants suggested that the differences between epidemic and endemic occurrence of rinderpest could be explained by differing contact rates between individuals and groups within populations of cattle in different farming systems.
Session 2: Diagnosis and surveillance
Three papers described the need for and ways of implementing training in laboratory and clinical diagnosis for laboratory and field staff. The WRLR provides important assistance with research, epidemiology and the development of improved diagnostic tests. A sensitive “pen-side” test for rinderpest has been developed by the WRLR and is currently being field trialled in Africa. The WRLR with support could provide electronic networking for rapid communication of results. The Joint FAO/IAEA Division provides valuable support for surveillance through a number of funding mechanisms and would be prepared to assist further with establishing regional and global networks for improved diagnostic co-ordination and reporting.
Discussion
Several participants emphasized the necessity for effective surveillance and reporting combined with submission of samples to the WRLR for genetic analysis. It was noted that some countries have not demonstrated sufficient commitment to actively search out rinderpest in their cattle populations and that this needs to change if GREP is to stand a realistic chance of success.
The valuable role of the WRLR was noted and countries with rinderpest or suspected rinderpest were encouraged to submit samples to it; currently the WRLR is not receiving enough samples for effective molecular epidemiological studies. One reason for this is the difficulty experienced in organising the transport of samples and it was suggested that FAO Representation offices could be requested to assist with submission of samples. The need for improved differential diagnosis was raised but the WRLR requires additional funding for manpower to do this. Accreditation of diagnostic laboratories is being considered though the necessity for this was questioned.
The Chairman (Dr Donaldson) stressed the importance of active reporting systems which must be demonstrated to be in place before the OIE can certify a country as free from rinderpest infection. Dr Raja (Pakistan) suggested that most developing countries have inadequate reporting systems and he was supported by other participants. There was considerable input and consensus on the need for improved active disease surveillance, including increased submission of samples to diagnostic laboratories, and various ways in which this could be achieved were considered. Experience suggests that some form of incentive is probably needed in certain situations though the possible hazards of financial rewards were noted. Better dialogue with both farmers and veterinary staff was considered to be important as was the importance of reacting swiftly to try to solve the stockowners' problems, and the requirement for more streamlined and simplified sample submission.
Dr Mariner (Kenya) stressed the value of participatory dialogue using questionnaire surveys for rinderpest investigation and tracing patterns of movement over time. He also suggested that this approach will become critical when confirming eradication.
Dr Taylor (EC India) suggested that good information gathering was perhaps more valuable than good vaccination and in this education of farmers was of great importance; good information favours the timely elimination of rinderpest outbreaks. Dr Freeland (ODA UK) supported this statement and observed that both farmers and the lower echelons of veterinary departments do not always welcome the consequences of a diagnosis. A key issue in rinderpest control has always been the willingness of countries to acknowledge openly the presence of rinderpest and, as a result of coordinated regional programmes and interaction with EMPRES, countries are increasingly forthcoming.
There was general agreement that training is essential to the future success of GREP both for laboratory and field staff, including junior staff at the level which interfaces directly with stockowners. It was also pointed out that there is little to be gained by training people if they have no support afterwards.
Session 3: Communications and GREP
Two papers described the ways in which conventional and computer-based communication methods can help to extend the concept and methodologies of GREP to participants at all levels from the stockowner to national, regional and global management teams. Both stressed the benefits of close collaboration with campaign organizers from project inception, and the need to be clear about what each communication component was intended to do and to whom it was to be targeted.
The training modules developed, and being developed, by the Advanced Veterinary Information System (AVIS) consortium of FAO, Institute for Animal Health, Telos and OIE were described; these are to be translated into other languages besides English.
Discussion
Dr Birmingham (WHO) indicated the importance of good communication between all parties engaged on an eradication programme and stressed the value of feedback in reporting systems, through regular and frequent news bulletins, to motivate staff in the field. She also stressed that communication with the public, essential for successful uptake of control procedures, must extend far beyond the preparation of posters for promoting public awareness. All aspects of communication media need to be exploited to the full in high profile publicity campaigns.
The increasing availability of useful computer mapping techniques was noted together with the value of Geographical Positioning Systems for recording the exact geographical location of outbreaks and sampling sites.
Session 4: Technical strategies
Dr James (UK) set the scene for discussing technical strategies by providing a socio-economic justification for eradication, based on the impact of the disease on food security, and stressed the mutual interdependence of countries in eliminating the threat of rinderpest. This could probably only be achieved by adherence to a time-bound global eradication programme (GREP) firmly based on the OIE Pathway mechanism for attaining validated freedom from infection.
The papers by Dr Mariner (Kenya) and Dr Leyland (UNICEF) described the value of participatory extension techniques including the role of community based animal health workers under veterinary supervision both in rinderpest control and disease surveillance. These have proved to be particularly effective in pastoral areas and in zones affected by civil strife. In terms of rinderpest immunisation it was demonstrated that community animal health workers working in difficult areas were at least as efficient as conventional veterinary services working in accessible areas. There is convincing evidence that areas of rinderpest endemic persistence in southern Sudan and Ethiopia were yielding to this approach.
The GREP strategies presented by Dr Rweyemamu (FAO) developed at the December 1995 GREP Consultative Group Meeting were presented as a basis for discussion and inclusion into the GREP Blueprint. This paper acknowledged the limited incidence of rinderpest and therefore the need for a new strategy which relies on national commitment to the OIE Pathway rather than mass vaccination of national herds. It was stressed that any outbreak of rinderpest outside the known endemic foci should be regarded as an international emergency and that national and regional rinderpest eradication throughout the GREP areas should now emphasize the principles of: EARLY WARNING through enhanced and purposeful rinderpest disease surveillance supported by appropriate laboratory diagnostic technology and targeted sero-surveillance, EARLY REACTION based on practical contingency plans and specific rinderpest emergency preparedness and contingency planning.
Dr Birmingham (WHO) described the global poliomyelitis eradication programme stressing the surveillance requirements which relied heavily on case finding; surveillance must provide data for action. Other requirements considered important are effective coordination with performance indicators to monitor progress, communication with campaign workers and the public (to promote social mobilisation), and adequate technical assistance at all levels. The concept of regional progression towards eradication rather than consideration of individual countries was accented. Her paper drew parallels with eradication programmes for measles virus and poliomyelitis virus, and suggested that many of the lessons learnt there would be of value to GREP.
Four papers by Mr Davies (UK), Dr Cheneau (FAO), Dr Geering (FAO) and Dr Roeder (FAO) addressed the concepts of a global early warning and early reaction capability for transboundary animal diseases of epidemic potential, with rinderpest as a prime focus, together with the essential components of emergency preparedness through contingency planning and appropriately structured and orientated veterinary services. Dr Provost (OIE) presented the OIE standards for epidemiological surveillance systems for rinderpest in the context of the OIE Pathway to verified freedom from rinderpest infection.
Discussion
In considering the economic justification for rinderpest eradication, the lack of sound data was highlighted and participants indicated that the costs of maintaining institutionalised vaccination might have been underestimated and therefore the benefits of eradication were also probably underestimated.
Drs Mariner (Kenya) and Leyland (UNICEF) were commended on their pioneering work which addressed the most appropriate populations in terms of rinderpest persistence. Expansion of the community-based system to other marginalised communities was advocated as a means of complementing conventional approaches for several diseases, not just rinderpest.
A broadly ranging discussion of strategies for EMPRES and GREP endorsed the EMPRES philosophy of early warning, early reaction, research and coordination with respect to GREP. It was agreed that the concept of ecological zonation for delineating areas requiring different approaches was valid and the concepts developed at the GREP Consultative group Meeting were a valid basis on which to build; the global situation was considered to be essentially unaltered in the last six months except for improving epidemiological definition in eastern Africa. Among subjects raised were the need to establish independent certification commission, the anomaly that exists between the OIE Pathway as adopted by the OIE International Committee and the OIE International Animal Health Code with respect to the adoption of zoning for declarations of freedom and the need to redefine the requirement for cessation of vaccination as a prerequisite for a declaration of provisional freedom from rinderpest disease to ensure that it is taken to mean the cessation of all immunisation of cattle and buffaloes intended to prevent the transmission of rinderpest virus in these species; the use of heterologous vaccines in cattle and buffaloes as a replacement for homologous rinderpest vaccine was considered an unacceptable practice.
In discussing the means of promoting progress towards validated freedom from rinderpest, Dr Taylor (EC India) considered that the OIE Pathway itself prompted the desired and timely actions and, thus, entry onto the Pathway was a most important action. It was decided that regions and individual countries needed performance indicators to measure progress and that these need to include quantifiable indicators of effective disease surveillance; it was suggested that this might be an appropriate activity for OIE.
Session 5: Financing
This component of the meeting was aimed at considering global rinderpest eradication from the viewpoint of the donor community, without whom coordinated regional eradication programmes would not be possible. Two papers dealt with EU perspectives with respect to the well-established PARC and the nascent South Asian Rinderpest Campaign of which the Indian, Bhutanese and Nepalese components are already established.
Mr Dale's paper (EU, Brussels, presented by Dr J. Thomson in Mr Dale's absence) placed PARC firmly within the context of needing to meet the challenge of feeding a rapidly growing population, a need which requires increasing efficiency of the livestock sector of agriculture. It was indicated that PARC has made a significant contribution to developing the livestock sector through addressing some of the key issues: rinderpest eradication; privatisation of veterinary services; cost recovery for veterinary services; and, regional coordination. The emphasis of PARC is now conceived to need broadening its mandate to change towards taking into account animal health problems other than rinderpest (e.g. contagious bovine pleuropneumonia, foot-and-mouth disease and trypanosomosis) as well as a broad spectrum of production-related subjects such as intensification of mixed croplivestock farming systems; land use planning; safeguarding biodiversity; and livestock production training for veterinarians.
Dr Vandersmissen's (EU Brussels) paper, dealing with the EC's involvement and experience in Asia, stressed that EC's actions in development of the animal production and health sector were inseparable from the European Union's political and economic relations with Asian countries as outlined in the EU New Asia Strategy including strengthening political dialogue, contributing to peaceful development and stability and promoting economic reform. Thus, it stressed the necessity of viewing epidemic disease control, and specifically rinderpest eradication, as a component of activities aimed at sustainable development (strengthening) of veterinary services as a service to the livestock sector of agricultural production. Dr Vandersmissen indicated that projects for strengthening of veterinary services are being prepared for Pakistan, Bangladesh and south-east Asian countries. In addition the EC will soon finance a South Asia Rinderpest Eradication Campaign -Support Project within a memorandum of understanding with the South Asian Association for Regional Co-operation (SAARC).
The third paper from Dr Sidahmed (IFAD) highlighted success of the relationship between IFAD and FAO in the campaign to eradicate New World Screwworm after its introduction to North Africa and indicated that this working relationship was being built on to develop new initiatives for animal disease surveillance in support of animal disease control and the FAO EMPRES initiative.
Discussion
Whilst welcoming the EC's commitment to PARC and SAREC in strengthening veterinary services in support of developing livestock production, several participants expressed their concern at relegation of the importance of rinderpest eradication which had been the original driving force of PARC and SAREC and counselled against too broad a dissemination of activities before that goal had been achieved lest the campaign lose momentum and falter as had previous internationally-coordinated rinderpest control. The meeting recommended that special action was required for Pakistan and Afghanistan.
