PESTES DES PETIT RUMINANT (PPR)

This is a rinderpest-like viral disease of small ruminants like goats and sheep. Goats are more susceptible than sheep. The dwarf breeds of goats and red sokoto goats are known to be very susceptible to the infection. The disease is found in West Africa although it has been reported in the Middle East.
Etiology
The disease is caused by RNA virus belonging to the genus Morbillivirus. Morbilli means measles and the family paramyxoviridae. The virus is antigenically related to rinderpest, human measles and canine distemper virus.
Distribution
The disease is endemic in West Africa. It has been reported in the Middle East.
Transmission
The mode of transmission is by aerosols. Infection spreads readily when healthy and infected animals are in close contact. It is also possible by ingestion of contaminated food and water.
Clinical signs
The following are the clinical signs:
Fever
Anorexia
Shivering
Serous nasal discharge which later becomes mucopurulent
Erosions/ulcers in mouth; oral scabs
Coughing and fast breathing due to secondary pneumonia
Increased salivation
Emaciation and dehydration
Severe diarrhea

Pregnant animals may abort
Death occurs where there are severe diarrhea and pneumonia.
Pathology
Extensive erosions of the oral and pharyngeal mucosae
Zebra stripes are present in gastrointestinal tract
Petechial haemorrhages may be seen in tissues
Presence of intracytoplasmic and intranuclear inclusion bodies in epithelial tissues of alimentary and respiratory tracts.
Red consolidated areas in the lungs.
Lymphocyte depletion of lymphoid tissues.
Intranuclear inclusions in the reticuloendothelial cells in the sinuses and germinal centres of lymphnodes
Diagnosis
This is based on the clinical findings on the epidemiology and post-mortem findings. Isolation and recognition of the virus is very important. Other tests used are hemeagglutination inhibition test and hemeagglutination test.
Differential diagnosis
Rinderpest
Footh and mouth disease
Blue tongue
Orf/ contagious pustular dermatitis/ ecthyma
Sheep and goat pox
Coccidiosis
Immunity
Recovered animals are known to possess durable active immunity.
Prevention
This is by vaccination using homologous PPR virus vaccine. It is important to separate newly purchased animals from old stock. The newly purchased animals should be kept away from the old stock for at least 2 months before mixing with the rest of the animals.
Avoid purchasing animals suspected of the disease or animals from infected herds.
Treatment
There is no treatment as such. All treatment are directed against secondary bacterial infections by giving high doses of long acting antibiotics.
The infected animal should be dewormed.
Some people recommend giving codeine because it suppresses coughing.
Fluid therapy should be administered in dehydrated cases.
Sulfonamides should be given if antibiotics are absent.