§Rinderpest
is an acute or subacute highly contagious
disease of cattle, characterized by erosive or hemorrhagic lesions of
all mucous membrane
§Classical
form of rinderpest is one of the most lethal diseases of cattle
§In
1889 – kill 90% of cattle of sub-Saharan Africa
§In
1992, the Food and Agriculture Organization (FAO) of the United Nations began
the Global Rinderpest Eradication Programme - vaccination campaigns and
surveillance
§
Between 2002 and 2011 there were no reported field cases of rinderpest
§In
2011 OIE - declaration of global freedom
from rinderpest
§First
animal pathogen eradicated from world
§Only
one other virus, human smallpox, has ever been completely eliminated from
nature
ETIOLOGY
•Rinderpest virus – SS RNA
•Genus: Morbillivirus
•Family: Paramyxoviridae
•Only
one serotype - effective vaccine
HOST
•Most cloven-hooved animals (order Artiodactyla) are susceptible to RP
•Mainly cattle and buffaloes, but also reported in sheep, goat and pigs
TRANSMISSION
•Direct contact
•Nasal/ocular
secretions
•Feces,
urine, saliva, and blood
•Contaminated food or water
•Indirect contact
•Fomites
PATHOGENESIS
•Virus reach to nasopharyngeal
mucosa→ binds to host CD150 on activated T cells, B cells and dendritic cells
of tonsils and regional lymphnodes
→ Virus replication → Go in the blood →
Viremia → dissemination to nasal, oral and alimentary mucosal cells → Virus replication causing focal necrosis,
erosion, and fibrinous exudation (diarrhea and dehydration) → Infect lymph
nodes and GALT → destructions of lymphocytes → Immunodeficiency → Secondary
bacterial infection →Death from severe dehydration and occasionally from
secondary infections
CLINICAL SIGN
•Incubation period: 1 to 2 weeks
•Prodromal phase - Lasts approximately 3 day
•Acute high fever with anorexia,
decreased milk yield, lacrimation
•Erosive phases
•Necrotic epithelium of oral
cavity visible
•Focal erosions and ulcers of the
upper GI and respiratory tracts
•Diarrhetic phase - develops 1–2
days after the onset of mouth lesions -
'Shooting diarrhoea'
•Severe bloody diarrhea,
prostration, dehydration, shock, death
•Profound leukopenia,
hemoconcentration, hypoproteinemia, and
hypochloremia
MACROSCOPIC MATHOLOGY
•Dehydrated, soiled, fetid carcass
•Focal erosions and ulcers of the
upper GI and respiratory tracts
•First lesions on inner surface of
lower lip, adjacent gum, cheeks, ventral tongue
•Rarely affects rumen, reticulum
•Erosions, ulcers, edema of
abomasum
•Hemorrhagic, necrotic, edematous
Peyer’s patches
•Hemorrhage and congestion of
cecum, colon, rectum (zebra stripes)
•Congestion, swelling and erosion
of vulval and vaginal mucosa
MICROSCOPIC PATHOLOGY
•Lymphoid necrosis with loss of
mature lymphocytes and replacement by plasma cells and macrophages
•Focal mucosal necrosis just above
basal layer, extending to the surface
•Necrosis of intestinal crypts
with resultant erosions and ulcers
•Syncytia; intracytoplasmic and
intranuclear eosinophilic inclusion bodies in infected epithelial cells
•Syncytia – Common in Oral mucosa
than GIT
•Minimal inflammation
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