Seroprevalence of contagious bovine pleuropneumonia in Ethiopian highlands (West Wellega zone, Bodji District)

Contagious bovine pleuropneumonia (CBPP) is a respiratory disease of cattle caused by Mycoplasma mycoides subsmycoides small colony. CBPP has been and is still a major cause for concern for African countries (due to mortality, animal-production losses and cost of monitoring and control). A cross sectional study of the herd and animal seroprevalence of contagious bovine pleuropneumonia (CBPP) using stratified sampling; competitive cELISA test was carried out in a zebu cattle-producing district of Ethiopia, representative of the Ethiopian highlands fringe where CBPP is assumed to re-emerge after the phasing out in 1994 of Rinderpest and CBPP bivalent vaccination program. A total of 2508 zebu cattle (Horro breed) from 300 herds were examined serologically and for characteristic clinical signs of CBPThe herd seroprevalence was 4.6% in average representing 15 herds. The herd seroprevalence was ranging from 2.0% to 8.5% in 3 strata representing increasing herd size. In conclusion, the clinical signs observed in the survey were not providing a good picture on the disease prevalence

Experimental inoculation of goats with the contagious bovine pleuropneumonia

The objective of the trial was to determine the susceptibility of goats to the contagious bovine pleuropneumonia (CBPP) agent. Four inoculation routes – subcutaneous, endobronchial, intrapleural and intraperitoneal – were tested. One of the goats infected intraperitoneally died of peritonitis. The CBPP agent was isolated again from the ascitic fluid. The serological tests, competition ELISA in particular, revealed the occurrence of serological conversions in a number of animals. This should pave the way to further field studies to determine if goats in contact with CBPP-affected bovines may be naturally contaminated

Conceptual Model to Predict the Intraherd Spread of Contagious Bovine Pleuropneumonia

Contagious bovine pleuropneumonia (CBPP) is a contagious respiratory disease of cattle caused by Mycoplasma mycoides subsp. mycoides small colony. CBPP heavily constrains cattle farm development in Africa and results in mortality, decrease in animal production, and control costs. A conceptual model of CBPP spread within an infected herd (vaccinated or not) is proposed. It was developed based on today’s epidemiological knowledge of the disease. This conceptual model was translated into a mathematical model, which can be used to test various CBPP control strategies at the herd level. It will have to be tried out in various CBPP epidemiological contexts of Africa and to be tested against future experimental results in order to be validated and eventually improved. Finally, it will be essential to conduct surveys during CBPP outbreaks, carry out clinical trials, and promote publications of the detailed results of these actions to assess in a more reliable manner the epidemiological parameters that control the model behavior

Within-herd spread of contagious bovine pleuropneumonia in Ethiopian highlands

Contagious bovine pleuropneumonia (CBPP) is a major threat for cattle health and production in Africa. This disease is caused by the small-colony type of Mycoplasma mycoides subspecies mycoides (MmmSC). Transmission occurs from direct and repeated contacts between sick and healthy animals. Veterinary services recently reported a resurgence of CBPP in the province of West Wellega, in the Ethiopian highlands. A research program was set up to estimate the epidemiological parameters of the within-herd infection spread. A follow-up survey was implemented in 71 sampled herds of the Boji district (West Wellega province). Fifteen herds were classified as newly infected and used in a serological- and clinical-incidence study. The overall 16-month cumulative sero-incidence risk was 34%. Clinical cases were recorded for 39% of the seropositive cattle; case-fatality risk was 13%. There was no evidence of benefit on infection spread of CBPP-control measures used locally by farmers (isolation or antibiotic treatments of sick animals). This might be related to a lack of power in the statistical analyses or to a quality problem for the medications used (and more generally, for health-care delivery in the Boji district)

Contagious Caprine Pleuropneumonia

Contagious caprine pleuropneumonia (CCPP), caused by Mycoplasma capricolum subsp. capripneumoniae, is an OIE-listed disease affecting goats and wild ungulate species. CCPP is present in Africa, the Middle East, and Central Asia, but its exact distribution is unknown, particularly in Asia. It is enzootic in the Middle East and East Africa, while it has only been sporadically reported in North and Central Africa and, though suspected, has never been identified in West Africa. In addition, there are very few studies reporting the prevalence and losses induced by CCPP, which are greatly underestimated. This uncertainty over the distribution and impact of CCPP is partly due to the fastidious nature of its etiologic agent, which is difficult to identify, particularly when it circulates in an insidious, mild, or asymptomatic form, favored by the use of antibiotic treatments. However, specific molecular and serological tests are now available for the diagnosis of CCPP, even in the absence of isolation. The main limitation of CCPP surveillance remains the lack of awareness by veterinary services. Vaccines based on inactivated antigens in saponin can induce good protection and their variable quality may now be assessed using a specific ELISA. However, they are very expensive, and there is a paucity of vaccine producers to satisfy their demand. Efforts must urgently be directed to the development of cheaper, quality-controlled vaccines to be extensively used in the field. The global campaign to eradicate “peste des petits ruminants” by 2030 may be a great opportunity to target other goat diseases such as CCPP