In June 2001, FAO finalized an electronic conference on CBPP that stimulated debate on key issues in preparation for the third FAO/OIE/IAEA/OAU-IBAR Consultative Group meeting scheduled for 2003. The e-conference attracted many participants, including policy-makers, researchers, field officers, project managers and directors of veterinary services. The issues raised during the conference were:
The majority of the participants expressed the opinion that the control of CBPP should be considered more of a public than a private good and, as such, should still remain within the public domain. In this regard, effective coordination of research, maintenance of disease-free areas, support for the development of better tools and information systems, and the establishment of an enabling environment, were all considered as public goods. However, although opportunities for synergy between the private and public sectors in the control of CBPP exist, these must be carefully planned to ensure continued mutual advantage.
Repeated vaccination with T1 44 could be sufficient to reduce disease incidence in national herds. Although it is essential that six-monthly vaccination be carried out, unfortunately this is not happening in most countries, and explains the negative attitude towards vaccines.
Reference was made in the e-conference to the success that many countries have registered in the past in their fight against CBPP, using simple tools such as movement control and effective compensation to farmers after stamping out. These countries, though then lacking any clear understanding of the pathogenesis and immunology of the disease; had, however, what mattered - a coherent political will and the right legislative framework.
In the light of the above, it was suggested that control measures against CBPP in African countries should be implemented without further delay, with regular review where necessary. "We do not have to wait until all the basic immunological events occurring in affected cattle are clearly understood," was how one participant summed it up.
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At the same time, it was also observed that the development of a new generation of CBPP vaccines has been slow. Attempts to improve vaccine efficacy, ranging from the modification of streptomycin resistant strain T1 SR to the recent immunostimulating complex (ISCOM) preparations, have not been completely successful either. This suggests that empirical vaccine preparation without prior knowledge of the protective antigenic components of the causative organism of CBPP, Mycoplasma mycoides subspecies mycoides Small Colony type (MmmSC), is fraught with risks.
The establishment of improved diagnostic reagents would have to rely heavily on the re-sults of immunological studies and genome analysis to facilitate identification of carriers.
New tools would have to be developed to detect chronic carriers and smarter, more reliable tools would be required to switch from the present herd-based diagnosis to individual diagnosis. At the same time, more and better funding from international and national research organizations is required.
Coordination was deemed essential to the timely success of research efforts, and the FAO/IAEA Coordination Research Programme on the Diagnosis and Control of Contagious Bovine Pleuropneumonia in Africa provides a forum for dialogue among stakeholders. It is a link between the various activities of PACE and regional FAO CBPP programmes.
There was a strong perception that the use of antibiotics at least predisposes or may cause infected animals to become chronic carriers of CBPP. There is little information on the effect of treatment on the generation of carriers, and on the role of carriers in the spread of the disease. Various reasons were stated why the use of antibiotics is not currently recommended for CBPP. These include:
The importance of research on treatment to ascertain which antibiotics may be useful and the field situations that would warrant their use, validation of regimes and documentation of any adverse effects was recognized and should be accorded a high priority. Money invested in determining the true efficacy and risks of treatment would probably be of most direct benefit to farmers, given the reality of what is happening in the field, where farmers use antibiotics nonetheless.
Without an effective veterinary service to underpin surveillance, movement control, vaccination strategies and other control measures, there is little prospect of a progressive control of the disease. Pastoral communities should be co-opted in the control of CBPP, by enhancing their own traditional coping mechanisms such as self-imposed quarantine of infected cattle for a realistic period of time. However, to gain pastoralists' confidence and cooperation would also entail explaining to them the rational basis for disease control protocols.
Several participants stressed the importance of CBPP impact assessment studies, and observed that quite often governments' and bureaucrats' negative attitudes towards CBPP control stem from the fact that the full impact of the disease is not fully known and appreciated. It was considered that the baseline data necessary to effect such economic impact studies would have to be generated by the national veterinary services, through their epidemiology networks or units.
The importance of HACCP principles in CBPP management was also stressed, particularly in consideration of the scarce or dwindling resources available for disease control. Furthermore, it was suggested that a HACCP plan could be developed for a particular locality based on the epidemiology of the disease present in that locality.
Insufficient funding of national veterinary services in Africa was identified as one of the reasons leading to a marked deterioration of the disease status in the continent. The lack of close surveillance almost certainly means that the extent of the disease is not fully realized. Currently, there is a decrease in the number of infected foci in Namibia but, at the same time, there are increasing incursions of the disease into Zambia from Angola.
Solutions such as cattle movement control are usually not practicable in many parts of the continent, and this clearly contributes to the spread of the disease. Transhumance, drought and culture often complicate this situation further.
Any plan for CBPP control must be systematic and viewed in terms of regions, because the measures taken by any country have a direct bearing on the disease status of neighbouring countries.
It is hoped that the regional recognition of CBPP status would prompt concerted efforts to: coordinate resource management; realize an accurate description of the spread of CBPP through the enhancement of field and laboratory surveillance; realize active population sensitization; and promote dissemination of relevant information.
The consequences of CBPP are devastating, and efforts must be made to assess its impact, through cost-benefit analyses of various control measures. The issue should be brought to the attention of national Ministries of Agriculture in appropriate regional forums and at national levels through PACE national activities.
Finally, the control of CBPP requires political will, which must be built before the necessary legislative back-up is provided.
Source: Contagious bovine pleuropneumonia - to eradicate, control or live with the disease. FAO June-November 2001, available at www.fao.org/ag/AGA/AGAH/EMPRES/info/CBPP/CBPPe-conf.vb.htm
