Detection of Contagious Caprine Pleuropneumonia and Concurrent Diseases in Outbreaks Presenting with Respiratory Signs in Small Ruminants in Tanzania

Aims: To establish the prevalence and concurrent diseases in outbreaks presenting with respiratory signs, major associated clinical signs and postmortem lesions and proportions of those diseases in clinically and autopsied small ruminants for a proper diagnosis and control strategies.

Study Design: Purposive outbreaks investigation.

Place and Duration of Study: Department of Global Health, School of Life Science and Bio-Engineering (LiSBE), Nelson Mandela Institution of Science and Technology (NM-AIST) between September 2016 and December 2018.

Methodology: We included investigations of outbreaks of diseases presenting with respiratory signs in small ruminants reported from five agro-ecological zones in Tanzania. Small ruminats with clinical signs or postmortem lesions suggestive of respiratory involvement were subjected to clinical or postmortem examination. Samples from all examined animals were tested in the laboratory using conventional polymerase chain reaction (PCR) to confirm the tentative diagnosis.

Results: A total of 205 small ruminats were examined and tested, of these 72.2% and 20.8% were goats and sheep respectively. In goats, 79.1% (117/148) and sheep, 28.1% (16/57) were confirmed to have concurrent infections, and pneumonic pasteurellosis and peste des petits ruminants (PPR) for goats, and PPR for sheep being mostly involved diseases. Contagious caprine pleuropneumonia (CCPP) was detected in 16.1% (n=205) of the animals, and was significantly high in goats (p=0.003, OR=7.3) than sheep. Pneumonic mannheimiosis (prevalence = 9.3%) was less likely to affect goats than sheep (p=0.047, OR=0.38). In goats (n=148), detection of all diseases was significantly (p<0.05) low in clinically examined animals except pneumonic pasteurellosis and PPR, (p =0.056, OR=2.1) and (p=0.096, OR=2.15) respectively, though the difference was not significant. In sheep (n=57), CCPP was significantly (p=0.005, OR=0.17) more likely to be detected in clinically examined animals.

Conclusion: In investigations of outbreaks presenting with respiratory signs in small ruminants, it is important to consider concurrent infections in the interventions and control strategies to be deployed, which may include development and use of multivalent vaccines.