Rhabdoviridae

Question 1

Rhabdoviridae: morphology

Answer 1

Enveloped with large spikes, bullet-shaped, helically coiled cylindrical nucleocapsid

Question 2

Rhabdovirus RNA encodes 5 important proteins

Answer 2

L (Large): RNA-dept RNA polymerase (transcriptase)
G(Glycoprotein): forms envelope spikes
N(Nuceloprotein): RNA to form viral nucleocapsid
P(Phosphoprotein): binds L protein to nucleocapsid
M(Matrix): asso. viral nucleocapsid and lipid envelope

Question 3

Rhabdovirus genome

Answer 3

single molecule linear, neg-sense, ssRNA

Question 4

Rhabdovirus replication takes place in ____, maturation happens by ___

Answer 4

the cytoplasm

by budding through the plasma membrane

Question 5

Lyssavirus is known to cause

Answer 5

Rabies (genotype-1 Lyssavirus)

Question 6

Rabies: transmission

Answer 6

Mostly by bite or scratch of infected animal via saliva

through mucous membranes or wounds, aerosol, and transplanted organs is possible

Question 7

Rabies main host reservoir in urban cycles are

Answer 7

Dogs

Question 8

Rabies often infect “dead-end” hosts which include

Answer 8

Humans and most herbivores

Question 9

Rabies main host reservoir for sylvatic cycle is

Answer 9

Bats

also shunks for U.S. (raccoons, red fox)

Question 10

Rabies CS in bats

Answer 10

Mostly asymptomatic

may develop paresis/paralysis, disoriented, aggression

Question 11

Rabies viruses spreads in the body via

Answer 11

Nerves

G proteins binds to axon terminals

Question 12

Rabies: Bites to the ___ (location on body) have the greatest risk

Answer 12

The face,

greater degree of innervation = shorter incubation

Question 13

Rabies: uncommon routes of entry involve the __ (location) traveling by __ (nerve)

Answer 13

Intranasal exposure

Trigeminal nerve/ganglia

Question 14

When rabies reaches the brain if it replicates in the ___ it leads to the ___ form, However, if it reaches the ___ it develops the ___ form

Answer 14

Limbic system, Furious form

neuro-cortex, dumb form

Question 15

High concentration of rabies virus is contained in the __ (organ)

Answer 15

Salivary glands

Question 16

T or F

There are macroscopic lesion of rabies infected animals

Answer 16

False

Histological evidence is seen

Question 17

T or F

Little immunological response is seen in rabies infection

Answer 17

True

Very little antigen is released

Question 18

Rabies: 3 clinical phases of infection

Answer 18

Prodromal
Acute excitative (furious)
Paralytic/End stage (dumb)

Question 19

Rabies: prodromal period

Answer 19

Virus shedding and temperament change before CS are seen

Question 20

Rabies: Furious form CS

Answer 20

Excitment/aggression, Disinhibiton
Hydrophobia (pharyngeal paralysis)
excessive salivation, extreme response to light and sound, hyperesthesia

Question 21

Rabies: Dumb form CS

Answer 21

encephalitis, paralysis, ataxia, muscle weakness
convulsive seizures, coma, resp. arrest
Death

Question 22

Rabies: diagnosis

Answer 22

Direct FAT- rabies antigens in brain

Negri bodies, RT-PCR, Intracerebral inoculation of weanling mice

Question 23

Rabies: Control

Answer 23

Quarantine, vaccine

little treatment possible

Question 24

Vesiculovirus causes

Answer 24

Vesicular Stomatitis

Question 25

Two important serotypes of vesiculovirus

Answer 25

Indiana serotype | New Jersey serotype- more virulent, widespread

Question 26

VS: transmission

Answer 26

through breaks in mucosa or skin | Arthropods

Question 27

VS: pathogenesis

Answer 27

localized ulceration that can lead to epithelium being slough

Question 28

VS: CS

Answer 28

ulcerated lesions on tongue and coronary band, excessive salivation, fever, anorexia

Question 29

VS: first sign of infection in cattle and horses

Answer 29

Excessive salivation

Question 30

VS: first sign in pigs

Answer 30

lameness

Question 31

VS: diagnosis

Answer 31

Virus isolation, serum samples, CFT, VN | RT-PCR

Question 32

Vesicular stomatitis is indistinguishable from other vesicular diseases, except in __(animal)

Answer 32

Horses | lesions characteristics of VS

Question 33

VS: control

Answer 33

Reportable disese | quarantine areas, pest control, vaccines (with some success)

Question 34

Ephemerovirus causes

Answer 34

Bovine ephemeral fever | 3-day sickness

Question 35

BEF: hosts

Answer 35

cattle and water buffalo

Question 36

BEF: transmission

Answer 36

Arthropod borne

Question 37

BEF: is asso. with ___ of blood

Answer 37

Buffy coat

Question 38

BEF: CS

Answer 38

polyseroitis of joints, pleural, and peritoneal surfaces High neutrophil in effusion fluids fever, excess salivation, serous nasal discharge, dyspnea, stiffness, lameness

Question 39

BEF: diagnosis

Answer 39

virus isolation (difficult), IC inoculation of sucking mice

Question 40

BEF: control

Answer 40

attenuated virus vaccine | vector control