Rabies
 Synonym :
 Hydrophobia
 Lyssa
 Rabies is a neurological, invariably fatal, viral
disease of mammals characterized by nervous
signs, salivation, paralysis , non suppurative
encephalitis and intracytoplasmic inclusion bodies
(Negri bodies)
• Rabies virus (Genotype 1) – Neurotropic
Two biotypes
❶Fixed virus:
• Laboratory vaccine virus
• Adapted to CNS by passage
• Tropism to CNS
• Not secreted in saliva
• Marked neuronal denegation
• No Negri bodies
❷Street virus :
• Produced natural occurring
diseases
• Tropism to CNS and salivary
glands
• Secreted in saliva
• Negri bodies in 70 % cases
All warm blooded animals /mammals (wild and
domestic)
Pathogenesis
Perivascular cuffing, Babe’s nodules and Negri bodies are
pathognomonic for rabies
• Babe’s (Glial)nodules – composed of Microglial cells
• Negri bodies – hallmark of rabies infection
• Carnivores – hippocampal neuron
• Herbivores – Purkinje neuron of cerebellum
• Laboratory tests
• Fluorescent antibody test – recommended by
both WHO and OIE – ‘Gold-standard’ test
• Immunoperoxidase methods
• Enzyme-linked immunosorbent assay (ELISA)
• Mouse inoculation test
• RT – PCR
• Virus neutralisation test in cell culture
BVD / MD
Bovine Virus Diarrhoea /
Mucosal Disease
 BVD /MD is a viral disease of young cattle (6–24 mo
old), associated with various clinical presentation can
range from inapparent or subclinical infection to acute
and severe enteric disease to the highly fatal mucosal
disease complex characterized by profuse enteritis in
association with typical mucosal lesions.