Peste des Petits Ruminants: Aetiology, Pathology, Immunology, Disease Status in Africa, Diagnosis, Control, Prevention and Treatment: A Review

Peste des petits ruminants (PPR) is a disease of economic and veterinary importance leading to considerable economic losses. PPR affects small domestic and wild ruminants. Sheep and goats are the natural hosts of PPR but cattle, pigs, African buffaloes and camels are also affected by the PPR virus. Clinical signs seen are mainly fever, mucopurulent nasal and ocular discharges, cough, dyspnoea, gastroenteritis leading to severe diarrhoea. The post mortem lesions seen are congested lungs, congestion of gastrointestinal tract, especially the discontinuous streaks of congestion, which is referred to as Zebra stripes or Zebra markings, oedematous and congested retropharyngeal and mesenteric lymph nodes, linear haemorrhages in the intestinal mucosa and splenomegaly. PPR infection is characterized by a rise in packed cell volume (PCV), increase in haemoglobin concentration (HbC), leukopenia with lymphopenia. The serum alkaline phosphatase, alanine aminotransferase and aspartate aminotransferase activities are elevated, blood urea nitrogen and creatinine concentrations are also elevated. The disease is also characterized by disseminated intravascular coagulopathy (DIC) evidenced by prolonged prothrombin time (PT), prolonged activated thromboplastin time (APTT), thrombocytopenia, and hypofibrinogenemia. In PPR infection, serum biomarkers of oxidative stress such as vitamins A, C, E and glutathione activity decreases while serum catalase, superoxide dismutase, glutathione reductase and xanthine oxidase increase. Diagnostic techniques include histopathology, virus isolation, immunocapture enzyme-linked immunosorbent assay (icELISA), Competitive Enzyme Linked Imunnosorbent Assay (cELISA) and Combined Indirect ELISA (CI-ELISA) agar gel immunodiffusion, real-time polymerase chain reaction (RT-PCR), reverse transcription-loop mediated isothermal amplification assay (RT-LAMP), Luciferase immunoprecipitation system (LIPS) and immunohistochemistry. Therefore, this review focused on the aetiology, epidemiology, pathology, immunology, and disease status in Africa, diagnosis, control, prevention, treatment and control of this disease.