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A study was implemented to investigate the presence of contagious caprine pleuropneumonia (CCPP) in East Turkey. This study was based on clinical surveillance in the field, surveillance at regional slaughterhouses and regular submission of suspected lesions to regional laboratories. The results showed that the agent of CCPP, Mycoplasma capricolum subspecies capripneumoniae (Mccp), could be detected by culture and specific polymerase chain reaction from 37.5% (12/32) of lung samples taken from goats of ten different herds. This agent was also isolated from two of 13 sheep samples (one from the lung and the other from a nasal swab). Mycoplasma capricolum subsp. capripneumoniae was isolated in pure culture and characterised at a finer molecular level. The East Turkish isolate was found to be closely related to another strain of Turkish origin, as well as to Mccp strains isolated in Tunisia. The isolation of Mccp from sheep lung lesions brings the strict host-specificity of this pathogen into question. It may also indicate that Mccp presents a risk for wildlife in the region. Such results, the authors believe, demonstrate that adequate risk assessments should be undertaken in Turkey and neighbouring countries.

In 1990 an outbreak of contagious bovine pleuropneumonia (CBPP) occurred in Italy. Subsequent surveillance for CBPP was based on random sampling in bovine herds, serological controls on all animals moved from the herd of origin and controls on slaughtered animals. Official tests employed were the complement fixation test (CFT) and bacteriological isolation and typing. A total of 33,856 serum samples collected from herds in CBPP-free regions were used to define CFT specificity, while samples from 595 animals from infected herds were employed to define the sensitivity. Ninety-nine animals from three infected herds were used to estimate the sensitivity of the isolation technique. Results showed the specificity of CFT (threshold +1:10) to be 98% and sensitivity to be 63.79%. The sensitivity of the test did not change significantly, regardless of whether the lesions were caused by acute or chronic infection. The sensitivity of the isolation technique was 54.1%.

The initial draft of this document was prepared in June 1993 by the Ad hoc Group on Contagious Bovine Pleuropneumonia Surveillance Systems of the Office International des Epizooties. That draft was then amended in February 1997 by the Group of experts convened at the request of the International Committee to examine issues relating to the surveillance of the disease, with particular reference to the effects of vaccination programmes on surveillance systems. This updated report includes the following: epidemiological and other factors which influence the choice of surveillance systems. Sampling and surveillance strategies. Diagnostic methods applicable to surveillance systems. The repercussions of vaccination on surveillance systems.

The diagnosis of contagious caprine pleuropneumonia (CCPP) has often been considered difficult. This is because of the confusion that can arise with other mycoplasmoses of small ruminants. Symptoms and lesions can be similar and the isolation of M. capricolum subsp. capripneumoniae (MccF38) requires skilled technicians. Once MccF38 strains are isolated, their identification should not be difficult. New techniques, such as polymerase chain reaction, now offer the possibility of identifying MccF38 directly from dried samples. However, the isolation of MccF38 strains is always required for an official declaration of infection. Until now, the official serological test has been the complement fixation test; the main drawbacks being lack of sensitivity and specificity and also the short persistence of antibodies detected by this technique. The specific competition enzyme-linked immunosorbent assay has now been developed and should enable wide serological enquiries to determine the real prevalence of the disease. Antibiotic treatments are effective but may not prevent persistence in latent carriers. An inactivated vaccine with saponin as an adjuvant has been produced in Kenya, which protects goats for approximately one year.

While it is easy to diagnose contagious bovine pleuropneumonia (CBPP) in an animal in the acute clinical stage, subacute and chronic forms are more difficult to diagnose. Recourse to laboratory tests is essential to confirm any suspicion of CBPP. As standard diagnostic procedures (isolation, culture, biochemical tests, serological tests) are lacking in specificity and sensitivity, improvements are needed. Progress in molecular biology techniques has led to new tests, among which are the polymerase chain reaction (PCR) and the enzyme-linked immunosorbent assay (ELISA) using monoclonal antibodies. Application of these techniques to CBPP offers a number of advantages, and has considerably enhanced the specificity and sensitivity of diagnosis.

A serological test involves detection of specific changes, induced by a pathogen, in the properties or actions of serum of an infected host. The test may detect the presence in serum of either antibodies to the pathogen (produced by the host) or antigens (i.e. the infecting agent itself and/or its components). The many serological tests which have been developed for the diagnosis of contagious bovine pleuropneumonia (CBPP) are classified into two groups on the basis of this distinction. To date, no single serological test is able to detect all stages of the disease. Thus the choice of serological test (or combination of tests) will depend on the specific aim of the investigation. Meanwhile, a sensitive, specific and simple 'pen-side' test for the diagnosis of all forms of CBPP is still lacking.

Contagious bovine pleuropneumonia (CBPP), caused by Mycoplasma mycoides subsp. mycoides SC (small colony variant), is a disease which has been recognised for a long time. Serological testing is used most often for diagnosing CBPP in live animals. This method is based on a complement fixation test (CFT), the technique recommended by the Office International des Epizooties, which has an important role in detecting infected herds in regions known to be affected by the disease. Although this serological test is the most reliable method currently available, it has some major shortcomings in sensitivity and specificity. The author discusses the reasons for these limitations, which can raise difficulties in the interpretation of CFT results, and the possibilities and potential applications of the test.

An exact assessment of the animal health situation in a country is an essential element in formulating eradication and control programmes, and in regulating international trade in animals and animal products from that country. Due to a lack of human and technical resources, Veterinary Services in developing countries often lack precise knowledge on disease occurrence. Since the collection and transmission of reliable information on animal diseases in developing countries are major concerns of the Office International des Epizooties (OIE), a project aimed at improving this situation was implemented with international financial support. This project involved the development by the Centre for the Application of Methodology for the Diagnosis of Animal Diseases (CAMDA) of field kits for the diagnosis of the main diseases present in tropical Africa: rinderpest, peste des petits ruminants (PPR), contagious bovine pleuropneumonia (CBPP) and contagious caprine pleuropneumonia (CCPP). Several tests already exist, such as complement deoxyribonucleic acid (cDNA)-specific probes and polymerase chain reaction (PCR) for rinderpest and PPR, DNA probes and PCR for CBPP, capture enzyme-linked immunosorbent assay, the agglutination test and the immunobinding peroxidase test for CCPP, etc. With specific reference to these examples, the various problems faced by the OIE and CAMDA are reviewed.

Seventeen monoclonal antibodies (MAbs) raised against Mycoplasma mycoides ssp. mycoides small colony type (Mmm SC), the causative agent of contagious bovine pleuropneumonia (CBPP), were partially characterised. Six MAbs recognising a main protein of 70 kDa and showing reciprocal competition were found to be specific for Mmm SC, while the other MAbs showed different patterns of reactivity with Mycoplasma spp. within the mycoides "cluster". Sandwich enzyme-linked immunosorbent assay (ELISA) performed with different combinations of MAbs enabled the detection of Mycoplasma of the mycoides cluster in pathology samples and the specific identification of Mmm SC from the initial culture passages, overcoming the necessity for difficult and time-consuming biochemical and growth inhibition assays. A competitive ELISA based on Mmm SC-specific MAbs was able to measure anti-CBPP antibodies in cattle sera, and detected only the set of antibodies directed at Mmm SC-specific epitopes, thus avoiding the false-positive reactions occasionally observed with the complement fixation test.

Due to the difficulty in isolating Mycoplasma sp. type F38, two techniques for rapid detection are proposed in order to identify the presence of mycoplasmas of the mycoides group in samples of pleural fluid. A modification in the composition of isolation media promotes the growth of type F38 mycoplasmas and inhibits the growth of M. ovipneumoniae strains.