L21: Poxviruses (Waltzek)

Question 1

Poxvirus Virion Architecture

Answer 1

• large dsDNA viruses
• enveloped
• parapoxviruses are “brick shaped”
• very well dx with EM isnce they are so large and complex***

Question 2

papule vs. macule vs. pustule

Answer 2

papule: pigmented area (precursor to macule)
macule: small raised lesion
pustule: larger raised lesion
when any of the above ruptures, forms crust

Question 3

Poxvirus Dz general chars.***

Answer 3

• epitheliotropic, inducing proliferative lesions (hyperplasia, neoplasia, macule, papule, vesicle, pustule, crust)
• eosinophilic INTRACYTOPLASMIC inclusions (Bollinger bodies)***

Question 4

DNA viruses typically induce intracytoplasmic/intranuclear inclusions**

Answer 4

intranuclear

Question 5

Poxvirus host specificity and pathogenesis***

Answer 5

• broad host range
• ortho and parapoxviruses zoonotic***
• serious in immunocompromised
• contains genes for intracytoplasmic existence and immune evasion genes

Question 6

most important pox viruses in vet med. Why?**

Answer 6

capripoxviruses: sheeppox, goatpox, lumpyskin disease viruses
- high mortality, economic loss in young
- morbidity in adults causes loss of milk and/or meat
- expanding in geo. distr.
- notifiable foreign animal diseases

Question 7

Name 6 genuses of poxviruses in domestic animals. Which are zoonotic?***

Answer 7

Orthopoxvirus (zoonotic) - BROAD
Parapoxvirus (zoonotic) - narrow
Capripoxvirus - narrow
Suipoxvirus - narrow
Leporipoxvirus - narrow
Avipoxvirus - narrow

Question 8

Genus orthopoxvirus contains which virus(es)? Range?

Answer 8

cowpox virus; Europe

Question 9

Genus parapoxvirus contains which virus(es)? Range?

Answer 9

Pseudocowpox virus
Bovine papular stomatitis virus
Orf virus
WORLDWIDE

Question 10

Genus capripoxvirus contains which virus(es)? Range?

Answer 10

Sheeppox virus (Africa, Asia)
Goatpox virus (Africa, Asia)
Lumpyskin disease virus (Africa)

Question 11

genus suipoxvirus contains which virus(es)? Range?

Answer 11

swinepox (worldwide)

Question 12

genus leporipoxvirus contains which virus(es)? Range?

Answer 12

myxoma virus; Americas, Australia, Europe

Question 13

genus avipoxvirus contains which virus(es)? Range?

Answer 13

fowlpox; Worldwide

Question 14

reservoir for cowpox

Answer 14

rodents

Question 15

is cowpox zoonotic?

Answer 15

Y

Question 16

what other animal can be infected with cowpox?*** CS?

Answer 16

cats. (Cowpox rare in cows, NOT rare in cats since they prey on reservoir rodents!)***
CS: fever, skin lesions

Question 17

Dx of cowpox

Answer 17

EM
isolation of virus from cell culture
isolation on chorioallantoic membrane of the chick egg

Question 18

pseudocowpox virus belongs to which genus? Zoonotic?

Answer 18

Parapoxvirus. Zoonotic (causes milker’s nodule)

Question 19

pseudocowpox virus chars.

Answer 19

• mild dz in dairy cattle
• assoc. with poor hygiene
• can spread to calves during nursing
• dx by EM

Question 20

pseudocowpox CS

Answer 20

• causes proliferative teat lesions w/ characteristic horseshoe shape*
• 2ary bacterial mastitis

Question 21

Bovine papular stomatitis virus belongs to which genus? Zoonotic?

Answer 21

Parapoxvirus. Y

Question 22

Bovine papular stomatitis chars.

Answer 22

• common incidental infection in beef cattle worldwide
• effects suckling calves
• no tx
• dx by EM

Question 23

Orf belongs to which genus? Zoo?***

Answer 23

Parapoxvirus. Y (localized lesions with occasionl lymphadenopathy)

Question 24

Orf general chars.

Answer 24

• occurs in sheep/goat worldwide
• cause of contagious ecthyma, pustular dermatitis, and sore mouth
• most common in young lambs; restricts suckling
• lamb can spread to udder of ewes
• rapid spread w/n flock
• resistant in environment
• recovered animals only immune for few months

Question 25

CS of orf

Answer 25

- lesions at oral mucocutaneous junctions, muzzle/nostrils | - rare systemic spread

Question 26

Dx of Orf

Answer 26

- rapid spread in young animals - typical scabs around mouth - high morbidity, low mortality - EM

Question 27

transmission of capripoxviruses

Answer 27

- respiratory route, direct contact, biting fly vector | - African Buffalo wild reservoir

Question 28

2 forms of sheeppox and goatpox virus

Answer 28

1) Malignant - more common - depression, fever, nasal d/c, skin lesions on mucosa 2) Benign - skin lesions only

Question 29

pathogenesis, Dx, Tx, and control of sheeppox/goatpox virus

Answer 29

Path: replication in resp. lymph nodes, viremia, 2ary skin lesions Dx: CS, virus isolation, EM Tx: supportive Control: cull, quarantine. Vax not effective.

Question 30

sheeppox, goatpox, lumpyskin disease belong to which genus? Zoo?

Answer 30

Capripoxvirus. NO

Question 31

lumpy skin disease vs. sheep/goatpox

Answer 31

- causes similar resp. and skin lesions, lymphadenopathy, edema - has higher morbidity (100%) and lower mortality (1-2%) - distinguish from pseudolumpy disease, which is a herpesvirus**

Question 32

swinepox CS

Answer 32

- red papules --> raised hard elevations --> crusts | - usually benign with mild fever

Question 33

swinepox transmission/Dx/control

Answer 33

- swine louse vector - direct contact uncommon - Dx: EM - Control: eliminate lice

Question 34

Avipoxvirus chars.

Answer 34

- affects poultry/wild birds - fowlpox affects chickens - transmitted by arthropods, scabs - can persist in environment

Question 35

Fowlpox (type of Avipoxvirus) lesions

Answer 35

eosinophilic intracytoplasmic inclusion bodies (Bollinger bodies)