Flaviviridae

Question 1

Flaviridae: General

Answer 1

Spherical, Immature- two membrane asso. proteins (prM and E)

Mature- prM is cleaved

Question 2

Flaviridae replication takes place in

Answer 2

The cytoplasm

Maturation occurs in the intracytoplasmic membrane

Question 3

Two biotypes of BVDV

Answer 3

Non-cytopathogenic (ncp)

Cytopathogenic (cp)

Question 4

ncp- pathogenesis

Answer 4

Uncleaved form of NS2-3 protein, evades apoptosis
invades placenta- PI in calves
congenital, repro, enteric disorders

Question 5

cp- pathogenesis

Answer 5

From mutation in ncp biotype- cleavage of NS2-3 produces non-structural protein NS3
induces apoptosis in cultured cells
mucosal disease in PI cattle with ncp biotype

Question 6

BVDV genotypes

Answer 6

Type 1 and 2
Type 1 more frequent
both have cp and noncp viruses

Question 7

BVDV: transmission

Answer 7

Direct contact: all body fluids

Transplacental, airborne, mechanically, fomites

Question 8

BVDV: outcomes

Answer 8

subclinical infection, repro failures, PI calves, mucosal disease of calves, thrombocytopenia congenital defects

Question 9

BVDV: mucosal disease acute CS

Answer 9

Severe diarrhea, dull coat, runny nose, ulcerated oral cavity, erosion of esophagus and peyer’s patches, hemorrhage of abomasum, rumen ulcer, ulcer of coronary band

Question 10

BVDV: mucosal disease chronic CS

Answer 10

Diarrhea, inappetence, emaciation, rough hair, chronic bloat

Question 11

BVDV: diagnosis

Answer 11

virus isolation, PCR, ELISA

Question 12

BDVD: treatment

Answer 12

Vaccinate, cull PI

Question 13

Pestivirus causes

Answer 13

Classical swine fever

Reportable

Question 14

CSF: transmission

Answer 14

Direct, fecal-oral, aerosol, fomites, transplacental

Question 15

CSF primary site of infection is the ___ (organ), spreads by ___

Answer 15

Tonsils

Lymphatics

Question 16

CSF: Acute CS

Answer 16

drowsy, depressed, Hyperemia,, cyanosis, conjunctivitis, diarrhea, hemorrhagic viscera and bladder, button ulcer colon
abortion, goose-stepping, venous congestion of brain

Question 17

Pathogeumonic lesion of acute CS of CSF

Answer 17

Turkey egg kidney

Question 18

CSF: diagnosis

Answer 18

virus isolation, PCR, ELISA, FAT

Question 19

CSF: control

Answer 19

Reportable

burn carcasses, quarantine farms, hygiene, avoid feeding undercooked meat products,, vaccine

Question 20

T or F

you can differentiate between a vaccinated animal and a naturally infected one

Answer 20

False
Not when vaccinated with live attenuated vaccine
Differentiates with DIVA

Question 21

Flavivirus can cause

Answer 21

West Nile virus

Question 22

WNV: reservoir

Answer 22

Birds

Question 23

WNV: transmission

Answer 23

mechanically

human-human exposure via contact with blood, breast feeding, etc.

Question 24

WNV is classified into __(#) lineages

Answer 24

7

only 1 and 2 seen in human disease (1a most freq.)

Question 25

WNV: CS in humans

Answer 25

rashes, flu-like signs, non-neurological (myocarditis, Hepatitis, nephritis)
**Neuro-invasive- encephalitis, meningitis, meningoencephalitis

Question 26

WNV: CS in horses

Answer 26

Mostly asymptomatic

some CNS signs- encephalomyelitis with ataxia

Question 27

WNV: control

Answer 27

Pest control, vaccine

Question 28

Louping (trembling) ill is a tick-borne disease that infects __(animals)

Answer 28

Sheep and red grouse

Question 29

Louping ill is most common on __(location)

Answer 29

British isles

Question 30

Louping ill- Tick vector

Answer 30

Ixodes ricinus

transtadial transmission

Question 31

Louping ill virus replication takes place in ___ (organ)

Answer 31

brain

Question 32

Louping ill: CS sheep

Answer 32

CNS signs, stiff bouncing movements (leaping in severe cases), muscle tremors

Question 33

Louping ill: CS in humans

Answer 33

non-specific, flu-like

CNS signs, hemorrhagic fever

Question 34

Louping ill: control

Answer 34

tick control, vaccinate