Calciviridae

Question 1

get their name from calix meaning

Answer 1

cup, b/c it has 32 cup shaped surface depressions

Question 2

general

Answer 2

nonenveloped, icosahedral, linear ssRNA

genomic RNA is infectious

Question 3

replication

Answer 3

cytoplasm

Question 4

Feline Calicivirus (FCV)

Answer 4

highly infectious pathogen of cats

genus: vesivirus

Question 5

Clinical syndromes

Answer 5

range from inapparent infections to typically mild or acute oral and upper resp. tract disease in cats
some strains induce lameness (limping syndrome)
highly virulent forms (FCV-VSD) emerged (USA)- systemic infection that is frequently fatal

Question 6

FCV pathogenesis

Answer 6

virus shed in oral, nasal and conjunctival secretions

transmission largely by direct contact (ingestion, inhalation, conjunctiva)

Question 7

Main site of replication

Answer 7

oral and resp. tissues
strains vary in their tissue tropisms and pathogenicity
can be found in feces and urine

Question 8

CS FCV

Answer 8

tongue ulcers (most prominent lesions)
sloughing oral ulcers and rhinitis
chronic ulcerative proliferative gingivostomatitis (possibly immune mediated reaction)
tongue ulcerative glossitis
pneumonia (acute exudative followed by proliferative intersitial pneumonia)

Question 9

Limping syndrome (associated lameness)

Answer 9

acute synovitis, thickening of synovial membrane and increased amount of synovial fluid in joint

Question 10

FCV-VSD virulent systemic disease

Answer 10

mortality rates as high as 50%
epizootics in USA, recently in europe
vaccinated cats have been affected suggesting that current vaccines may not protect against FCV-VSD
sign. difference from classical disease

Question 11

mechanisms of FCV-VSD

Answer 11

unclear, possible factors:
virus mutations
host and immune factors
environmental and management factors

Question 12

FCV-VSD pathology

Answer 12

ulceration of tongue, gingiva, hard palate, nasal cavity, pinnae, and haired skin
mild hyperemia to sloughing of the entire foot pad
broncho-interstitial pneumonia and necrosis of the iver, spleen and pancrease
infection of endothelial cells, resulting in vascular injury

Question 13

FCV-VSD clinical signs

Answer 13

pyrexia, subcutaneous facial and limb edema, crusted lesions, ulcers and alopecia on nose, lips, and ear, around eyes, and on footpads, anorexia, jaundice, alopecia, resp. distress, epistaxis

Question 14

Vesicular exanthema of swine (VES)

Answer 14

acute, highly infectious
characterized by fever and formation of vesicles on snout, oral mucosa, soles of feet, coronary band and between toes
lameness

Question 15

VES is indistinguishable from

Answer 15

foot and mouth disease
vesicular stomatitis
swine vesicular disease

Question 16

Is VES present in the USA?

Answer 16

No, it was declared free of VES in 1959