Rhabdoviruses

Question 1

Rhabdovirus example

Answer 1

Rabies

Question 2

Shape and characteristics of rhabdovirus

Answer 2

bullet-shaped, helical, enveloped
Negative, single stranded RNA,
(Replicates in cytoplasm)

Question 3

Replication

Answer 3

Virus binds to G-protein, has own RNA polymerase, (5 mRNAs)
Pinocytosis
Enters endosomes and RNP particles released into cytoplasm
5 mRNAs and full-length + RNA template created
Synthesize proteins (G protein in ER and Golgi, rest cytoplasm) and replicate genetic material, assemble, encapsulate, and bud from plasma membrane

Question 4

Rabies progression

Answer 4

20-90 day incubation
Prodromal phase 2-10 days, fever, weakness, headache), site of bite itches
Neurological phase 2-7 days: anxiety, confusion, agitation, confusion, abnormal behavior, hallucinations, insomnia, coma, hypotension, cardiac arrhythmia, death
Fatal once symptoms appear
Travel retrogradedly

Question 5

Epidemiology

Answer 5

Bite or scratch transmission
Reservoir: bat, foxes, raccoons, skunks
Domestic animals

Question 6

Diagnosis

Answer 6

Histopathology - mononuclear infiltration, perivascular cuffing of lymphocytes or polymorphonuclear cells, lymphocytic foci, babes nodules consisting of glial cells, negri bodies; Electron microscopy, Direct fluorescent Antibody test, Immunohistochemistry

Question 7

Control

Answer 7

Get animal, Administer vaccine after bite

Could try coma after symptoms

Question 8

Proteins encoded by rabies virus

Answer 8

nucleoprotein (N) that tightly encases genomic RNA
phosphoprotein (P) associated with RNP
Matrix protein (M) associated with envelope and RNP; may be central protein of rhabdovirus assembly
Glycoprotein (G) forms 400 trimeric spikes which are tightly arranged on the viral surface
Polymerase (L) associated with the RNP, RNA dependent RNA polymerase