Viral infections Flashcards
1
Q
A
Feline herpes virus
2
Q
What is swinepox?
A
caused by Suipoxvirus
- also caused by Vaccinia virus (that affects humans too)
lice and flies/mosquitos are vectors
causes erythematous macules
- progress through papular, vesicular, and pustular phases
- become umbilicated (“pox”)
3
Q
What is porcine dermatitis and nephropathy syndrome?
A
caused by co‐infection with PRRSV and Anellovirus
get immune complexes, vasculitis, and systemic coagulopathy
- erythematous to reddish‐purple macules and papules –> plaques
- edema and proteinuria
4
Q
What is foot-and-mouth disease?
A
caused by an Aphthovirus (an RNA virus)
primarily affects even-toed ungulates (not horses)
- humans are only very rarely affected (are by hand, foot, and mouth)
- can also affect hedgehogs and elephants
- pigs cannot serve as asymptomatic carriers (others can)
causes high fever for 2-6 days –> vesicles around mouth and hooves
- can lead to myocarditis and death
- can lead to abortion
- Morbidity varies from 50 to 100%
REPORTABLE! (foreign animal disease in US)
- severe implications for animal farming
- transmitted many way: contact, aerosol, fomites
- can be diagnosed via virus isolation or clotted blood
5
Q
What is pseudocowpox?
A
caused by Parapoxvirus bovis‐2
most common infectious cause of teat lesions
- classical “ring” or “horseshoe” lesion
is zoonotic
6
Q
What is the most common infectious cause of teat lesions in cows?
A
Parapoxvirus bovis‐2 (pseudocowpox)
7
Q
What is bovine papular stomatitis?
A
caused by Parapoxvirus bovis‐1
- transmission is via skin abrasions
erythematous macules and papules
- may become papillomatous or become crusted
lesions are usually on muzzle, nostrils, and lips
- can be in mouth, on teats, etc
a chronic form in calves is proliferative and necrotic stomatitis
also associated with “rat-tail syndrome”
is zoonotic
8
Q
What are the lesions in the cow most consistent with?
A
Parapoxvirus bovis‐2 (pseudocowpox)
9
Q
What are the lesions in the cow most consistent with?
A
Parapoxvirus bovis‐1 (bovine papular stomatitis)
10
Q
What does bovine herpesvirus‐2 tend to cause?
A
Herpes mammillitis
- occurs most commonly in lactating cattle
- sudden in onset, swollen, tender teats
- severity of lesions varies from dry erythematous skin to necrosis
- often painful
- decreased milk production and increased mastitis
- usually self-limiting
Pseudo-Lumpy Skin Disease
- looks like lumpy skin caused by Capripoxvirus
- mostly in southern Africa
11
Q
What is malignant catarrhal fever?
A
Usually caused by ovine herpesvirus 2 (OvHV-2) outside of Africa
- exists as a ubiquitous subclinical infection in sheep
There are at least 10 viruses associated with it
- AIHV-1 is predominant in Africa from wildebeest
Affects many even-toed ungulates
Initial clinical signs include fever, nasal discharge, anorexia, depression
- photophobia, lacrimation, and conjunctivitis develop
- muzzle is crusted and burnt in appearance (may become necrotic)
- hard palate and tongue develop ulcers
- get erythematous‐to‐purplish macules that can ooze/crust
–>particularly common on perineum, udder and teats
- one report where cutaneous lesions were primary signs in cattle
- can develop GI and neurologic signs
REPORTABLE IN MANY STATES
12
Q
What is bovine viral diarrhea?
A
Caused by Pestivirus
Have fever, diarrhea, nasal/ocular discharge, erosions/ulcers in oral cavity
- can develop erosions/ulcers elsewhere
Can have scales, crusts, hyperkeratosis, and alopecia
- esp occur on the neck, medial thighs, and perineum
In utero infections may cause generalized hypotrichosis
- spare the head, tail, and distal legs
13
Q
Which viral infection in cattle can cause generalized hypotrichosis that spares the head, legs, and tail when contracted in utero?
A
Pestivirus (bovine viral diarrhea)
14
Q
What does bovine herpesvirus‐1 tend to cause?
A
Infectious bovine rhinotracheitis
- respiratory form = fever, dyspnea, crusting of muzzle (“red nose”)
- genital form = pustules, necrotic white plaques on genitalia
15
Q
In ruminants and swine, what is vesicular stomatitis clinically indistinguishable from?
A
foot-and-mouth disease
swine vesicular disease
vesicular exanthema of swine
16
Q
In a multispecies farm setting, what can be used to differentiate vesicular stomatitis from foot-and-mouth disease?
A
If horses are affected
(but don’t, report both)
17
Q
What do Orthopoxviruses cause?
A
cowpox
feline cowpox
vaccinia (buffalopox virus, rabbitpox virus, horsepox)
- not common anymore since smallpox immunization ceased
camelpox
mousepox
monkeypox
18
Q
What are the member of the Poxviridae family?
A
Orthopoxvirus
Capripoxvirus
Suipoxvirus
Parapoxvirus
Molluscipoxvirus
Avipoxvirus
Leporpoxvirus
19
Q
What do Capripoxviruses cause?
A
sheeppox
goatpox
bovine lumpy skin disease
20
Q
What do Suipoxviruses cause?
A
swinepox
21
Q
What do Parapoxviruseses cause?
A
pseudocowpox (-bovis 2)
bovine papular stomatitis (-bovis 1)
contagious viral pustular dermatitis (orf)
Parapox virus of red deer
22
Q
What do Molluscipoxviruses cause?
A
molluscum contagiosum
23
Q
What do Avipoxviruses cause?
A
Fowlpox
Pigeonpox
conjunctivitis or darkened areas of skin in Lovebirds
24
Q
What do Leporipoxviruses cause?
A
Myxoma virus
Rabbit fibroma virus (Shope fibroma virus)
25
What type of viruses are Poxviridae?
enveloped DNA viruses
- envelope makes them resistant in the environment
share group-specific nucleoprotein antigens
many different ones including in reptiles
26
How are Poxviridae infections typically acquired?
entry through cutaneous or respiratory routes -->
gain access to the systemic circulation via the lymphatic system -->
- sometimes replication are cutaneous site can lead to entry into blood
become viremic -->
back to skin or target organs to cause disease
27
Where in the cell do poxviruses replicate?
cytoplasm of cells (despite being a DNA virus)
have replication “factories” that are independent of the host nucleus
28
What kind of inclusion bodies do poxviruses make?
more prominent eosinophilic inclusions are called Type A
- (3-7 mm in diameter)
- Borrel/Bollinger bodies
also have basophilic staining Type B cytoplasmic inclusion bodies
29
How do poxviruses induce cutaneous lesions?
degenerative changes in epithelium --> vesicular lesions
ischemia secondary to vascular damage
proliferative lesions via epithelial hyperplasia
30
What are the typical "pock/pox" lesion?
beginning as erythematous macules -->
become papular and then vesicular (sometimes nonexistent) -->
evolve into umbilicated lesions with a crust
- depressed center, erythematous border
- ulcerate more in cats
lesions often scar
31
What are the histopathologic findings associated with poxviruses?
cell swelling/ballooning degeneration
- esp of the stratum spinosum
Epithelia hyperplasia/acantholysis
- result in intraepidermal microvesicles
Necrosis, ulcers, crusts
Intracytoplasmic inclusions bodies
- typically find the eosinophilic Type A inclusion bodies
- may increase in size and density higher up in skin
Neutrophilic pustules
32
What is feline cowpox?
most commonly due to Orthopoxviruses
UK / Europe / very rare in North America
Reservoir hosts: voles, wood mice, ground squirrels, and gerbils
- occur when cats are wounded hunting rodents
Cause ulcers, plaques on head, neck or forelegs
- particularly ulcerative poxvirus
- can affect inside of mouth
33
Poxvirus
34
What is molluscum contagiosum?
caused by a molluscipox virus
worldwide in distribution
transmission occurs by intimate skin-to-skin contact and by fomites
- common in human children
immunoincompetent individuals more likely to be severely affected
- can affect immunocompetent animals too
horse and human ones are either the same or very similar
- horses may get it from humans
horses tend to have hundreds of lesions
- especially on the chest, shoulders, neck, and limbs
- 1- to 8-mm diameter papules that can be tufted
- usually become alopecic and covered with a powdery crust/scale
- may develop a small horn or turn into cauliflowerlike nodules/plaques
All lesions may not spontaneously regress
35
molluscum contagiosum (molluscipox virus)
36
What is lumpy skin disease in cattle?
caused by a Capripoxvirus
- similar disease can occur after vaccination with sheeppox
transmission occurs via insect vectors
- esp Stomoxys calcitrans
fever, anorexia, ocular/nasal discharge, hypersalivation, lymphadenopathy
Firm papules and nodules
- usually head, neck, legs, perineum, teats, udder, scrotum, and tail
can get leg edema --> areas of necrosis
IS REPORTABLE
37
What is contagious viral pustular dermatitis (“contagious ecthyma,” “orf”)?
caused by Parapoxvirus ovis
primarily seen in 3‐ to 6‐month‐old kid goats
- also affects sheep and camelids
tends to be seasonal (most common in kidding season)
papules --> vesicles --> pustules --> umbilicated, crusted
lesions become large and papillomatous
- esp if infected granulomatous tissue under crusts
Lesions are often painful
lips, muzzle, nostrils, eyelids, and pinnae most commonly affected (can affect inside of mouth)
- Oral lesions = red-gray-yellow papules & plaques surrounded by hyperemia
occasionally systemically ill
morbidity in kids can be 100%, mortality 1-20%
is zoonotic!
- 1/3 of humans get fever, lymphadenopathy, and erythema multiforme
38
Which breed of goat is more likely to have contagious viral pustular dermatitis (“contagious ecthyma,” “orf”)?
Boer and Boer cross goats
severe, generalized persistent dz with arthritis, pneumonia, & thymic involution
39
What is goatpox?
due to Capripoxvirus infections
- sometimes used to refer to impetigo in goats
Some strains cause disease only in goats, some in goats and sheep
Most often mild disease in the US
- disease is more severe in young animals
typically seen on lips, udder, and teats, and occasionally the perineum and medial thighs
doesn't seem to be zoonotic
40
What is sheeppox?
due to Capripoxvirus infections
- sometimes used to refer to impetigo in goats
Some strains cause disease only in goats, some in goats and sheep
Sheep may be more affected than goats (young>adult)
- can have pyrexia, depression, anorexia, rhinitis, etc
- can have respiratory distress and facial edema
- mastitis can occur when on teats
Can look like ulcerative dermatosis
41
What is rabbit fibroma virus (Shope fibroma virus)?
caused by a leporipoxvirus
closely related to myxoma virus
Discrete tumors occur on the legs or feet, on the muzzle, and around the eyes
- tumors are dermal and not attached to SC
Tumors will typically regress after a period of about 6 months
42
What is myxomatosis?
Caused by a Myxoma virus (Leporipoxvirus)
severe and often fatal disease
- fatality rates of 50–95% in European rabbits
- there is an endemic strain in CA with 100% fatality
transmitted primarily by insects (esp mosquitos)
classic nodular form
- nodules
- swelling and edema of the eyelids and genitals
- milky or purulent ocular discharge
- respiratory signs and bacterial pneumonia
- fever, lethargy, depression, and anorexia
peracute disease (highly virulent strain) = death in 10-12 days
Vaccines are available in some countries
43
What are Morbilliviruses?
a genus in Paramyxovirinae (includes parainfluenza)
includes canine distemper, measles, rinderpest
enveloped ssRNA virus
44
What is Rinderpest?
a Morbillivirus
rare, in Africa and Asia
can cause erythema, papules, oozing, crusts, and alopecia over perineum, flanks, medial
thighs, neck, scrotum, udder, and teats
cattle, sheep, and goats are susceptible
45
What are the histopathologic findings associated with canine distemper virus?
Ortho and/or parakeratotic hyperkeratosis
Epidermal hyperplasia
keratinocyte hydropic degeneration
Syncytial cells ( fusions of multiple uninuclear cells)
Intranuclear and/or intracytoplasmic eosinophilic inclusions
- usually cytoplasmic, nuclear are rare
secondary pustular dermatitis (pyoderma) common
IHC is available
46
Canine distemper
47
What are the clinical signs of canine distemper in dogs?
respiratory, GI, neurologic, cutaneous
- initially replicates in lymph nodes
can develop widespread impetigo
with chronic disease can get “hard pad disease”
- pawpad>nasal>ventral abdomen hyperkeratosis
- cutaneous lesions not always noted concomitantly
can also have enamel hypoplasia, hypoplasia, “old dog encephalitis", and thymic atrophy
48
What species are affected with canine distemper virus?
Dogs are considered reservoir host
Canidae (includes seals)
- in seals but they also have their own
Mustelidae (ferrets, skunks, otters, etc)
- ferrets are highly susceptible - mortality ~100%
- US has a canine distemper virus for ferrets
Procyonidae (racoons)
some Viveridae (palm civets)
some Ailuridae (red pandas)
some Ursidae (bears)
some Elephantidae (Asian elephants)
some primates (Japanese monkeys)
some large Felidae
49
What is phocine distemper virus?
A morbillivirus closely related to canine distemper virus seen in seals and sea otters
may not have respiratory disease
associated with cutaneous hyperkeratosis in the flippers and abdominal region of seals
50
What kind of inclusion body do morbilliviruses (ex. distemper) tend to have?
eosinophilic cytoplasmic (typical) OR nuclear
51
What kind of inclusion body do herpesviruses tend to have?
basophilic intranuclear
52
What kind of inclusion body do papillomaviruses tend to have?
basophilic intranuclear (dog and horse), cytoplasmic (cat)
53
What are the cutaneous lesions associated with FeLV?
Increased risk for many infectious disease
Increased risk of poor wound healing
Keratin mass on footpad; rarely nose and eyelid
Giant-cell dermatosis
- has syncytial-type cells in epidermis and ORS
- apoptotic keratinocytes surround them
Cutaneous lymphoma
54
What is the IHC when you are looking for FeLV in the skin?
gp70+ FeLV antigen
55
What are the cutaneous lesions associated with FIV?
Increased risk for many infectious disease
Increased risk for multiple MCTs
Papulocrusted dz with non-pruritic alopecia, scaling on head and limbs
- Histo: hydropic interface + occasional giant keratinocytes
56
What is FeSV (feline sarcoma virus)?
Variant of the FeLV virus that has incorporated proto-oncogenes
Cause of multicentric fibrosarcomas in young cats, liposarcomas in kittens
Possible relation to feline uveal melanomas
57
What is Herpesviridae?
Family of enveloped dsDNA viruses
three subfamilies:
- Alpha- (reproduce the fastest)
- Beta-
- Gamma-
include numerous viruses which can infect almost all animal
have an envelope, a nucleocapsid, DNA, tegument, and glycoprotein spikes
- spikes are named gB-M
icosahedral shape
58
What is the life cycle of herpes viruses?
viral particle contacts a cell with specific receptors -->
viral envelope glycoproteins bind to cell membrane receptors -->
virion is internalized and dismantled -->
viral DNA to migrate to the cell nucleus -->
all herpesviruses are nuclear-replicating -->
transcribe lytic viral genes and/or latency-associated transcript
- lytic viral genes are during symptomatic infections
- LAT is so that the virus can persist in the cell indefinitely
- long-term latency is symptom-free
59
What type of infectious organism are all viruses?
obligate intracellular
- so both virus and host have been subjected to selection and adaption
- viruses are selected for ability to evade the immune system
60
Which PRRs react to viruses?
viruses do not contain a lot of PAMPs
mostly recognize viral nucleic acids
- RIG-like receptors in cytosol for viral dsRNA --> trigger IFN-b
- TLR3 recognizes dsRNA viruses
- TLR7 and 8 recognize ssRNA viruses
- TLR9 recognizes CpG motifs in DNA
- NOD-like domains
- C-type lectins bind to viral glycoproteins --> block viral-cell interactions
61
Which cytokines are primarily produced in response to viral infections?
Interferons
Type I includes IFN-a and IFN-b
- IFN-a is produced by pDCs > lymphocytes and macrophages
- IFN-b can be produced by almost all viral-infected cells
Type II is IFN-y which is produced by antigen-stimulated Th1 cells
Type III are mostly local in GI, lungs, and BBB
62
When in the timeline of viral infections are type I interferons produced?
within a few hours
- produced when viral nucleic acids bind to TLR-7, TLR-9, and RIG-like
- via JAK/STAT pathways
high concentrations are achieved long before adaptive immunity develops
63
IFN-stimulated genes work through many pathways to have diverse effects on viruses including viral entry, replication, uncoating, protein assembly, or release as well as target affected cells. What are the 6 most important pathways?
1) The 2'5' A pathway (degrades RNA)
2) The Mx GTPase pathway (blocks viral assembly)
3) The protein kinase R pathway (prevents translation)
4) The ISG15 pathway (destroys viral proteins)
5) The viperin pathway (blocks lipid rafts)
6) Tetherin (prevents viral release)
64
What is viral RNA interference?
an ancient innate antiviral pathway (including plants, inverts, and mammals)
viral dsDNA is broken up by an intracellular nuclease called DICER -->
become small interfering RNA -->
loaded into the RNA-induced silencing complex (RISC) -->
bind to viral RNA and destroys it
65
How does antibody-mediated adaptive immunity respond to viruses?
Virus proteins are antigenic and antibody responses target these
Can also produce antibodies against viral proteins on infected cells
- direct for these cells to be targets
- antibody-dependent cell-mediated cytotoxicity (ADCC)
IgG, IgM, and IgA are produced
- IgG is quantitively most
- IgM is qualitatively superior
66
How does cell-mediated adaptive immunity respond to viruses?
most important at controlling viral diseases
Viral antigens can be expressed on MHC I
- CD8+ T cells recognize this as foreign
Viruses can be sensitized by interferons
- IFN-y and TNF-a can allow CD8+ T cells to kill virus without killing cells
Some viral antigens can be superantigens and induce Th2 cells
IFN-y can activate macrophages against intra-mac viruses
67
What are some ways that viruses evade the immune system?
Negative cytokine regulation
- block IFN
Viral versions of cytokines, chemokines and receptors aka virokines
- equine herpes virus makes a receptor for eotaxin-1 (CCL11)
- pox and herpesviruses can make a version of IL-10
Some viruses hijack antibodies or complement to help enter cells
Interfere with antigen processing pathways (esp MCH I)
Evade NK cells (stress-related protein MIC-B)
Alter the B cell system
- antigenic variation
- viruses resistant to antibody neuralization
- lentiviral infections can infect faster than antibody production/binding
Alter the T cell system (retroviruses and distemper)
Go into latency
Act synergistically with some bacteria
Inhibit/delay apoptosis of their host cell
68
What are some potential problematic sequellae to immune responses to viruses?
Type I hypersensitivities due to production of IL-4 and IgE
Type II hypersensitivity if too much cellular destruction
- ex. distemper encephalitis
Type III usually associated with prolonged viremia
- glomerulonephritis in EIA, Aleutian mink disease, FeLV, etc
- generalized vasculitis in EIA, Aleutian mink disease, MCF, etc
- uveitis ("blue eye") in dogs with adenovirus (usually resolves)
Virus where antibody presence increases susceptibility/severity
- antibody-dependent enhancement in FIV
69
What is Aleutian mink disease?
A parvovirus
in mink of Aleutian mink (gun-metal grey color)
these mink have Chediak-Higashi syndrome so predisposed
develop immune-complex-mediated lesions
immunosuppression prolongs survival
vaccination increases severity
70
How do you test for/detect viral infections?
PCR (viral DNA) or reverse transcriptase PCR (RNA viruses)
antigen/antiviral ELISA test typically used when bedside testing
lateral chromatography tests
hemagglutination inhibition
immunofluorescence
testing for antibodies to viruses
71
What types of herpes viruses are present in birds and reptiles?
alphaherpesviruses
- may the the earliest branch
72
What are the viruses of major important to veterinary dermatology within Alphaherpesvirinae?
Suid herpesvirus 1 (SuHV-1) - aka Aujeszky's disease/pseudorabies
bovine herpesvirus type I (BHV-1) - rhinotracheitis
bovine herpesvirus type 2 (BHV-2) - mammillitis, pseudo-lumpy skin
Equine herpesvirus 3 (EHV-3) - equine coital exanthema
Feline herpes virus type 1 (FHV-1) - rhinotracheitis and herpes dermatitis
All herpes infections in reptiles and birds
*herpes simplex virus types 1 and 2 (HSV-1 and HSV-2) in humans
73
What is feline herpes virus type 1?
An alphaherpesvirus
Causes feline rhinotracheitis
Causes URI symptoms, keratoconjunctivitis, rarely cutaneous/oral ulcers
Cause of herpesvirus ulcerative and necrotizing facial dermatitis
- ulcers are usually on face, distal limbs, trunk
- initial lesions near trigeminal nerve then spread due to grooming?
Latency in trigeminal ganglia (can activate with immunosuppression)
Maybe can cause exfoliative erythema multiforme
74
What is the histopathology finding associated with herpesvirus ulcerative and necrotizing facial dermatitis?
Ulcer + necrosis of epidermis and follicles
Crusts +/- vesicles
Eosinophilic infiltration (+/ flame figures), neuts can predominate
Eosinophilic/amphophilic intranuclear inclusions
- Marginated chromatin
- Not always seen
- Look at transition intact epithelia!
- +/- sebaceous glands
+/- Syncytial cells (multinucleated epithelia)
PCR, IHC may help diagnosis
75
Which a animal is particularly susceptible to feline herpesvirus-1 (FHV-1)?
Cheetahs (endemic in zoos)
Vaccination protocols are recommended
76
What type of viral inclusions do herpes viruses cause?
Intranuclear inclusions (eosinophilic/amphophilic, sometimes basophilic)
77
What does equid alphaherpesvirus 3 (EHV-3) cause?
Equine herpes coital exanthema
contagious venereal disease of horses
found in most parts of the world
transmitted via coitus, fomites, inhalation
causes vesicles, pustules, plaques, bullae, erosions/ulcers
- penis/prepuce, vagina, vulva, and perineum
- muzzles of foals if in contact with affected mares
- may be pruritic but usually not painful
- usually spontaneously resolves in 2-5 weeks
animals should not be bred while affected
78
What are the histopathologic signs consistent with equine herpes coital exanthema?
hyperplastic superficial and deep perivascular dermatitis
ballooning degeneration of keratinocytes
eosinophilic intranuclear inclusion bodies
may have intraepidermal vesicle formation
PCR detects virus in skin lesions
79
What are the viruses of major important to veterinary dermatology within Gammaherpesvirinae?
Ovine herpesvirus 2 (OvHV-2) - malignant catarrhal fever
Alcelaphine herpesvirus‐1 (AIHV-1) - malignant catarrhal fever
80
What do chelonia herpes viruses cause in seaturtles?
fibropapillomatosis aka green turtle fibropapillomas (GTFP)
- single to multiple benign fibro-epithelial tumors
grey patch disease of Green sea turtles
81
What does cyprinid herpes virus 1 cause?
Carp pox
Make smooth raised white lesions on body and fins
- may form large plaques and occasionally be pigmented
82
What cutaneous lesions do herpes viruses tend to cause in birds?
Papilloma-like lesions
- usually of the feet, can be elsewhere
83
What is pseudorabies (Aujezsky’s disease)?
caused by Suid herpesvirus 1 (SuHV-1) which is an alpha-herpesvirus
virus is shed in the saliva and nasal secretions of swine
- highly contagious
- usually asymptomatic in pigs >2 mo old but can cause abortion
- 100% mortality in pigs <1 mo of age (but not pruritic)
can affect sheep, cattle, goats, carnivores
- dogs and cats can get it from eating raw pork
causes maniacal pruritus, ptyalism, anorexia, ataxia, neuro disease
- pruritus is usually concentrated on the face ("mad itch")
- pruritus is considered a phantom sensation (virus not found at site)
- dogs esp can get jaw and pharyngeal paralysis
infected secondary host generally only lives 1-3 days
Diagnosis is made by virus isolation in tissue cultures, ELISA or PCR
84
What type of viruses are papillomaviruses?
small, non-enveloped dsDNA viruses
have an icosahedral capsid
- classified based on L1 proteins
- may also be classified as causing warts or asymptomatic
usually species-specific (with exceptions)
usually have a tropism for skin/mucous membranes
resistant to high/low temperatures, low pH, lipid solvents and detergents
- can exist at room temperature for 3 weeks
85
What are the capsid proteins of papillomaviruses?
Early genes - start being expressed in basal and suprabasal levels
- E1 and E2 are the major replication proteins
- E4 and E5 aid in genome amplification
- E6 is an oncogene, interferes with cell survival pathways (p53)
- E7 is an oncoproteins, cellular proliferation (retinoblastoma, pRb)
Late genes - expressed in upper spinosum and granulosum
- L1 is the major capsid protein, primary for interaction with host
- L2 is the minor capsid protein
86
How papillomaviruses enter the skin and from there, what is the lifecycle?
Are all contagious diseases but usually species-specific
direct/indirect contact with virus (usually through microinjuries) -->
- flies, etc may serve as fomites
- microinjuries allow for contact with stratum basale
infects the basal cells of the epithelium -->
interacts with receptors on cell surface so it is endocytosed -->
trafficked into cell and capsid is dissembled -->
enter the nucleus where they reproduce -->
initial amplification of the viral DNA -->
lifecycle depends on keratinocyte division and differentiation -->
- after initial stage is copied once per cell cycle
complete virions are assembled in stratum spinosum and corneum -->
virions are shed with stratum corneum
87
Why do lesions due to papillomaviruses occur?
majority of papillomaviruses do not cause a visible lesions
based on immune system of the host
- not all natural infections become clinical
- cellular immunity is mainly responsible for virus eradication
- humoral immunity protects the organism against reinfections
- age and immune status affect disease course
If develop exophytic warts, spontaneous regression at 4-8 weeks
- courses include regression / persistence / malignant transformation
88
What are the cytopathic effects of papilloma viruses and where are they best seen on histopathology?
Best seen in the mid- to upper-epidermis
- intracytoplasmic pseudoinclusions
- koilocytosis or clear cells
- clumped keratohyalin granules
- intranuclear inclusions are only present in upper epidermis
89
What are the histopathologic features typically associated with papilloma infections?
Can be exophytic or endophytic/inverted
- Endophytic: cup-shaped with centripetal projections and keratin core
Compact orthokeratosis and parakeratosis hyperkeratosis
Papillary epidermal hyperplasia with acanthosis
Lack of melanin pigment (except for pigmented varieties)
Increased mitotic index of basal cells
- Swollen with enlarged nuclei
- May form nest-like arrangements
Giant/clumped keratohyalin granules in the stratum spinosum
Koilocytes or clear cells
Intranuclear basophilic or eosinophilic inclusions
90
Why are many papilloma viruses non-pigmented?
May have alterations in melanogenesis and melanocyte-keratinocyte interaction
91
What are koilocytes?
Seen with papilloma viruses
keratinocytes with swollen, clear cytoplasm and a pyknotic nuclei
"sad raisin"
92
What are clear cells?
Seen with papilloma viruses
keratinocytes with swollen, blue-gray cytoplasm and enlarged nuclei
93
What is a squamous papilloma?
Not viral
Usually smaller and solitary
Face, eyelids, feet, conjunctiva
Histopath shows absent viral effects, less epithelial proliferation, and pointy /sharper fronds
94
What are the ideal ways to prove the presence of papillomaviruses in skin lesions on histopathology (not just visualizing inclusion bodies)?
Immunohistochemical analysis
- requires a decent amount of viral protein to provide a signal
- when positive, it clearly proves viral activity
Electron microscopy
- visualize characteristic viral structures to prove productive infection
In situ hybridization
- Used to locate nucleic acids of the virus in fixed tissues
- Show viral transcription when targeting RNA
95
Which methods can amplify viral DNA in cutaneous lesions for detection?
Rolling circle amplification
- amplify whole viral genomes independent of the sequence
- can be applied to fresh, but not fixed, samples
PCR assays have been established for the detection of CPV DNA
- DNA may be found independent of clinical symptoms
96
Which papillomavirus genus has variants that are not species-specific?
Deltapapillomavirus
97
What are the genera of papillomaviruses found in dogs?
Chi
- CPV 3, 4, 5, 8, 9, 10, 11, 12, 14, 15, 16, 18, 19, and 24
Lambda
- CPV 1 and 6
Tau
- CPV 2, 7, 13, 17, 20, 21, 22, and 23
98
What are canine cutaneous warts?
Second most frequent skin tumor in dogs <1 yr
- CPV1 or CPV2, or both types simultaneously
Causes exophytic lesions on skin
Usually on feet and around the face and ears
- Rare in anogenital region
Typically non-painful and regress in less than 3 mo
- But some may persist for 2 yr before regressing
- Kerry Blues and Cockers may have risk for longer infections
Progression to SCC is very rare
99
Which canine papilloma viruses have tropism for skin and oral cavity?
CPVs 1, 2, 3, 4, 6, 8, 13, 17, and 19
100
What is the clinical presentation of canine oral papillomatosis?
Frequent seen in young animals
Multiple exophytic smooth or cauliflower-like warts on the lips and mouth
- Tongue and esophagus only occasionally affected
- Potentially eyelids
Typically regress spontaneously within 4–8weeks
- rarely can develop further and spread to the haired skin
- rarely progress to SCC
Reports suggest that the transmission between dogs is possible
May also affect coyotes and wolves
- Same virus?
101
What is virus is canine oral papillomatosis usually associated with?
CPV1
102
What has regression in oral papillomavirus infections been linked to?
development of circulating antibodies against the L1 capsid protein of CPV1
103
What virus is viral cutaneous plaques/pigment viral plaques associated with?
Associated with Chipapillomavirus types
104
What is the clinical presentation of canine viral cutaneous plaques/pigment viral plaques?
Rarely reported in dogs
Associated with immunosuppressive conditions and breed predisposition
- Pugs have an autosomal dominant risk
Majority do not impact animal’s life
- Extensive plaques can cause pruritus and pain
Can regress spontaneously, but often permanent
105
What are the histopathologic finding associated with canine viral cutaneous plaques/pigment viral plaques?
Histopathology has slightly different finding than other papillomas
moderate acanthosis with scalloped configuration, hyperpigmentation, and clumped keratohyalin granules in the stratum spinosum are typically found
koilocytes as well as viral inclusions are usually not observed
106
What is potentially the human counterpart of canine viral cutaneous plaques/pigment viral plaques?
human epidermodysplasia verruciformis
107
What are the histopathologic findings associated with canine viral cutaneous plaques/pigment viral plaques?
Moderate acanthosis with scalloped configuration
hyperpigmentation
clumped keratohyalin granules in the stratum spinosum
koilocytes and viral inclusions are usually not observed
108
What are reported treatments for canine papillomas that are not regressing on their own?
Surgery, cryo, laser, photodynamic therapy
- "fire and ice"
Recombinant or autogenous vaccines
Type I interferons
Imiquimod
Cimetidine
Mycocellular bacterial cell
5-fluorouracil -- not in cats, neurotoxic
Azithromycin
Etretinate
Acyclovir
Intravenous injection of vincristine sulfate and immunoregulin
Taurolidine
Thuja occidentalis
Levamisole and thiabendazole
109
What is the clinical presentation of canine inverted papillomas?
Characterized by a growth downward into the skin
- raised and smooth nodules with a central pore filled with keratin
- endophytic, papillary projections of the epidermis into the dermis
Kerry Blues, Cockers, Bernese, Danes, Irish setters may be at risk
Have 4 types based on appearance
Type 1, classic inverted papillomas,
- large (1-2 cm), cup-shaped, grayish nodules with a large central pore
- usually on abdomen in small numbers or as solitary lesions
Type 2
- smaller (~4mm) dome-shaped flesh-colored papillomas
- may be disseminated over the whole body
Type 3
- even smaller (~2 mm) disseminated black papules
Type 4
- seems to be prone to induce interdigital lesions
110
What is different on the histopathology of Type 3 canine inverted plaques than others?
have intracytoplasmatic eosinopylic inclusions
111
What is virus are canine inverted plaques usually associated with?
CPV1
112
What is virus is canine conjunctival epithelial hyperplasia usually associated with?
CPV1
113
Which papilloma virus components are considered oncogenes?
E6 and E7 are major oncogenes
E5 is a minor oncogene
- some characteristic consistent with oncogenes in HPV 16
114
What are canine pedal papillomas?
One large study found they were 21.8% of anatomical sites in a 5 yr period
Happened in 17 dogs with X-linked severe combined immunodeficiency
- developed chronic cutaneous papillomavirus favoring the paws
- after bone marrow transplantation
- some transformed into squamous cell carcinomas
Median age of onset reported 2021 was four years
- others suggest multiple on footpads more common in 1-2yr olds
Usually have a history of lameness or paw licking
Could be associated with trauma
Can be inverted or not
- some can form discrete horn-like lesions in 2+ paws
Spontaneous regression in about half if localized on feet
- potentially if on paw pads there is less possibility of regression
115
What is Shope papilloma virus?
Occurs in wild rabbits
- infection of domestic rabbits is reported but rare
Transmitted via insect vector
Causes multiple horn-like lesions around the ears and eyelids
- can be removed with good cure rate
- ~75% can undergo malignant transformation to SCC
116
Which papilloma virus infections are considered fibropapillomas?
Bovine fibropapilloma, feline sarcoid, equine sarcoid
117
What are the genera of papillomaviruses in cats?
Dyothetapapillomavirus
- FcaPV2: tropism for skin
Lambdapapillomavirus
- FcaPV1: topism for skin and oral cavity
Taupapillomavirus
- FcaPVs 3 and 5: tropism for skin
- FcaPV4: tropism for the oral cavity
- FcaPV6: detected in the nasal planum
118
What cutaneous diseases has FcaPV2 been associated with?
viral plaques, BISC, cutaneous SCC and basal cell carcinoma
119
What cutaneous diseases has FcaPV1 been associated with?
cutaneous and oral papillomas
120
What cutaneous diseases has FcaPV3 been associated with?
viral plaques, BISC, cutaneous SCC, other cutaneous neoplasia
121
What cutaneous diseases has FcaPV4 been associated with?
related to stomatitis and BISC
122
What cutaneous diseases has FcaPV5 been associated with?
viral plaques and BISC
123
What cutaneous diseases has FcaPV6 been associated with?
cutaneous SCC
124
What cutaneous diseases is Bovine papillomavirus (BPV)-14 associated with?
feline sarcoids
125
What are feline viral cutaneous plaques?
Rare in cats
Affect mainly middle-aged or older animals
- may be FIV/FeLV positive
- may be immunosuppressed (if so, Demodex may be seen)
Sphinx or Devon Rex cats are at higher risk
- develop plaques more frequently and at a younger age
Present as multiple pigmented or non-pigmented lesions
Do not cause pain or pruritus
Typically on the head, face, and neck
126
Which feline papilloma viruses have been associated with cutaneous squamous cell carcinoma?
FcaPV2, 3 and 6
not clear if develops from viral plaques or directly from normal skin
127
What are the human “high-risk” papilloma viruses?
a-papillomaviruses (HPV-16 and HPV-18)
established to be oncogenic
128
What is the clinical presentation of feline sarcoids/cutaneous fibropapillomas?
Rare dermal neoplasms in cats
Most commonly diagnosed in young to middle-aged, DSH or DLH
- particularly those in rural areas
- may or may not be more common in males
Majority of sarcoids occurred on the face, particularly rostral locations
- Also reported on the digits, neck, ventral abdomen and tail
- Occasionally, lesions may be seen in the oral cavity
- May be a reflection of the territorial marking behaviors
Share many histologic similarities with equine sarcoids
Also comparable with non-vaccine-associated soft tissue sarcomas
129
What is the treatment of feline sarcoids/cutaneous fibropapillomas?
Wide surgical resection with complete histologic excision
- local recurrence rate is ~40% normally
- goes down to about 11% if you have good margins
Radiation doesn't seem to be very effective
Sr90 plesiotherapy was used for recurrence in one cat
130
What are the histopathologic features of feline sarcoids?
fibroblastic proliferation
- intimate association of an overlying, hyperplastic epithelial surface
long rete pegs extending into the spindloid tumor
*similar to equine sarcoids
131
feline sarcoid
132
Biopsy from a cat.
Feline papilloma
133
What is feline bowenoid in situ carcinoma?
a (mild) neoplasm
single or multiple scaly or crusting lesions within haired skin
- pigmented or nonpigmented skin
- become plaque-like --> nodular
- can progress to SCC (~15% of cases)
especially around the head and neck but can be anywhere
Devon Rex and Sphinx may be predisposed
134
Koilocytes
from a cat with BISC
135
Which papilloma viruses in cats are associated with bowenoid in situ carcinoma?
FcPV 2 and 3 are most common
4 and 5 also reported
136
What are the histopathologic findings associated with bowenoid in situ carcinoma?
Changes are confined to epidermis (+ often hair infundibulum)
Basal cell crowding
Loss of keratinocyte stratification & nuclear polarity
+/- “Windblown appearance” of keratinocyte nuclei
- Elongated, tilted in one direction
Melanization
Common mitoses, apoptosis, hyperkeratosis, erosions, crusts
Cytopathic effect in earlier stages (gone in chronic ones)
- Koilocytes, large keratohyaline granules
- inclusion bodies not normally seen
137
BISC
138
Shope papilloma virus
139
How can you tell BISC apart from SCC on histopathology?
SCC has a breach basement membrane
140
How can you tell BISC apart from actinic keratosis on histopathology?
Actinic keratosis has loss of polarity in stratum basale only
141
What papilloma virus has been associated with classical equine papillomatosis?
EcPV1
142
What papilloma virus has been associated with equine genital papillomatosis?
EcPV2
one case report of EcPV7
143
What papilloma virus has been associated with equine aural plaques?
EcPV3, 4, 5, and 6
144
What are the genera of papillomaviruses in horses?
Zeta-
- EcPV1
Dyoiota-
- EcPV2, 4, 5
Dyorho-
- EcPV 2, 3, 6
145
What are the clinical signs associated with classical equine papillomatosis?
Typically affect horses < 3 years
No predilection of breed or gender
Incubation period may last 60 days or longer
Start as 1-mm papules with a smooth, shiny surface and gray to white color
- then increase in size
- develop a hyperkeratotic surface with frond-like projections
10 to 100 lesions that may be arranged singly or coalesce
Sites most commonly affected include the muzzle and lips
- eyelids, paragenital regions, and distal legs can also be involved
Typically spontaneously resolves in < 4 mo, less commonly < 9 months
- if persists 10+ months, immunocompromise should be suspected
Most horses will develop complete immunity to the virus
- will not become reinfected
146
What are the clinical signs associated with equine genial papilloma/tosis?
single or confluent grayish papules, nodules, and/or plaques
- can develop frond-like papillomatous surfaces and keratinized horns
Affect the mucosa and skin of the external genitalia
- few to hundreds of lesions (might not be noticed until extensive)
Can progress to in situ squamous cell carcinomas --> SCC
- but may not progress
Mean age of horses is 16 to 18 years
Nonspecific clinical signs may include:
- purulent or sanguineous discharge from the preputial orifice
- altered micturition, preputial edema
- inability to expose the penis
- frequent protrusion of the penis
- wide-based stance and abnormal gait
Has been suggested to be sexually transmitted (like HPV-16 and HPV-18)
Do not self-resolve
147
What are the clinical signs associated with equine aural plaques?
Lesions affect the concave aspect of one or both pinna
- may be single or multiple to coalescing
- well-demarcated, shiny, erythematous or depigmented lesions
- typically covered with a whitish keratinous crust
- may cover almost the entire surface of the pinna
No predilection of sex or breed
Horses of any age can be affected (rarely < 1 year old)
May be asymptomatic or have ear and head hypersensitivity
Biting flies, especially black flies, may aggravate the symptoms
Not known to resolve spontaneously
148
What are some treatments for papillomas in horses?
Investigated for causes of immunosuppression
Surgical excision
Cryosurgery
Radiofrequency hyperthermia
Type I Interferons
Various topical caustic compounds (adjacent skin protected with petrolatum)
- podophyllin
- salicylic acid +/- castor oil or DMSO
- trifluoroacetic acid mixture
- tincture of benzoin
Intravenous or intralesional Propionibacterium acnes
Intralesional bacillus Calmette-Guerin (M. bovis), cisplatin, or IL-2
Imiquimod 5% cream
Autogenous vaccines (efficacy is questionable)
Topical tretinoin
Eastern blood root in zinc chloride
149
What protective measures should be take to prevent the spread of papillomas in horses?
Affected horses should be isolated
- immunologically susceptible horses should not be exposed
Clean fomites
Fly-control measures may also help prevent disease transmission
Hygiene for infected horses may help decrease change to SCC
150
What causes equine sarcoids?
BPV1 and less commonly BPV2
Invasiveness is associated with dysregulation in matrix metalloproteinases
- esp MMP 1 and MMP 9
Conflicting publications regarding the role of p53
In general, equine sarcoid fibroblasts exhibit cancer cell traits
- a number of abnormalities in immune mechanisms
- not associated with increased Ki67, pRB, or p53
- PDGFβ-R and MAPK pathway
Upregulation of Tregs in lesional skin versus distant, unaffected skin
- suggests local, Treg-induced immune suppression
E5 is a major oncoprotein in equine sarcoids
- found in some PBMCs
151
What is the most common skin tumor in horses?
Equine sarcoids
- also reported in horses, donkeys, mules, and zebras
152
What environmental and genetic factors appear to correlate with disease frequency in equine sarcomas?
Geldings and young horses were thought to be predisposed
- doesn't seem true anymore though rare in <1yr
Increased prevalence of equine sarcoid in particular families
Certain equine leukocyte antigens (ELAs) are associated
- impaired cell-mediated immunity at the level of epitope recognition
- impaired elimination of the virus-induced tumor cells
Quarter horses, TB, some WBs, Arabians, Appies at increased risk
Standardbreds are protected (low prevalence of the ELA W13 allele)
3 new candidate gene regions (chromosomes 20, 23, and 25)
- regulate virus replication and host immune response
- probably polygenetic
153
What how are equine leukocyte antigens (ELAs) are associated with sarcoid developmend?
Risk factors:
- ELA B1, W3, W5, W11 for Thoroughbreds and French/Irish/Swiss WBs
- LA A3 and W13 for Swedish Halfbreds
- A1 in Arabians and A5 in Freibergers
Disease course:
- A5 was associated with early onset
- W13 was associated with increased recurrence rates after surgery
154
Biopsy from a horse.
Papilloma
155
How are equine sarcoids transmitted?
Mechanism is not fully understood (results not consistent)
Direct contact with cattle or horses carrying BPV or fly bites
- Ex. Stomoxys calcitrans (stable flies)
- probably need (micro)trauma for infection (access to fibroblasts)
Effective immune response might inhibit the development of disease
Vertical BPV DNA transmission may occur
- BPV DNA found in the placenta
156
What are the 6 clinical forms of equine sarcoids?
Occult
Verrucose
Nodular
Fibroblastic
Mixed
Malignant/malevolent
157
Where are sarcoids typically located on horses?
may occur anywhere on the body
- majority of lesions occur on the head, neck, legs, and ventrum
14% to 84% of affected horses have multiple sarcoids
- more common with nodular form
- smaller “satellite” lesions
158
What is the disease progression like for equine sarcoids?
Progression is dynamic
Lesions are mostly persistent, resist therapy, and recur after therapy
- prognosis if on distal leg and periorbital region is more guarded
- some reports that 30% - 50% resolve without treatment
NOT a benign neoplasm even if it does not metastasize
159
What is the clinical appearance of occult equine sarcoids?
mildest, most stable, and superficial form
typically around the mouth, eyes, neck, and relatively hairless areas
1+ small cutaneous nodules (2–5 mm diameter) or hyperkeratotic areas
slow growing and may remain unchanged for years
- 65% underwent complete spontaneous regression
- may also progress to other forms
160
What is the clinical appearance of verrucose equine sarcoids?
Rough hyperkeratotic appearance with variable degrees of flaking and scaling
Over limited or wider areas of the body.
Typically on face, trunk, and groin/sheath areas
Predominantly slow growing
- Rarely aggressive until injured
- Regressed spontaneously in 32% of animals
161
What is the clinical appearance of nodular equine sarcoids?
Firm, well-defined subcutaneous, spherical nodules
Nodular type A are entirely subcutaneous
Nodular type B has varying involvement of overlying skin
Number of nodules varies widely from single to hundreds
Groin, sheath, or eyelid areas most common sites
Display moderate growth
- interference can lead to rapid growth/transformation
162
What is the clinical appearance of fibroblastic equine sarcoids?
Fleshy, ulcerated, aggressive appearance
Can be divided into 2 types
- Type 1: pedunculated with a limited or faint base palpable
- Type 2: broader-based (sessile) without a recognizable pedicle
--> often have a diffuse, ill-defined margin
Predilection sites are groin, eyelid, lower limbs, and coronary band
- Sites of skin wounds at any location
- Sites of any other types of sarcoid subjected to trauma or insult
Do not metastasize but can spread by local invasion
- May carry a very poor prognosis
More likely to recur after excision
163
What is the clinical appearance of mixed equine sarcoids?
Probably is a progression between types (2+)
Shows multiple characteristics
More complex mixed types may have worse prognosis
164
What is the clinical appearance of malignant/malevolent equine sarcoids?
Most severe but rare
Has infiltration of lymphatic vessels
- Results in nodules and cords of palpable tumor
Highly invasive and destructive
Apparent predilection for jaw and face, elbow, and medial thigh areas
- Can rapidly spread over a wide body area and grows quickly
Can be ulcerated and bleed
Poor prognosis
165
What are the typical histopathologic features associated with equine sarcoids?
increased density of dermal fibroblasts
- arranged in whorls, streams, and/or bundles
epidermal hyperplasia and hyperkeratosis
- rete peg formation
“picket fencing”
- fibroblasts aligned perpendicular to basement membrane
loss of adnexal structures
166
What are the treatments for equine sarcoids?
Multiple treatment protocols are reported, none work great
*Radiotherapy/interstitial brachytherapy
- Was considered gold standard
Sharp or laser surgical excision
- variable recurrence rates (18-70%)
- higher mitotic counts/fibroblastic type increase recurrence
Cryosurgery/laser/photodynamic therapy
Hyperthermia
Topical or intratumoural chemotherapy (ex. with cisplatin)
Plesiotherapy
Local electrochemotherapy (may have limited practical availability)
Imiquimod
Xxterra Herbal paste (Sanguinaria canadensis)
Topical aciclovir
Intralesional xanthates
BCG/ autogenous/ P. acnes vaccination (not recommended)
167
How can you differentiate equine sarcomas from other mesenchymal neoplasias?
Most are S100-negative
Positive for hypoxia-inducible factor-1 alpha (HIF-1α)
PCR-assisted detection of BPV-1/-2
168
Biopsy from a nodular lesion on a horse.
Sarcoid
169
What type of virus is feline calicivirus?
Unenveloped ssRNA virus in Vesivirus genus
Hides in tonsils
Can cause oral vesicles/ulcers, conjunctivitis, sneezing, pyrexia, lameness
- can lead to lymphoplasmacytic gingivitis (especially if FIV+)
- can cause pneumonia in kittens
- rarely affects skin and pawpads
Histopathology shows epithelial necrosis and ulceration +/- vasculitis
170
What does calicivirus cause in swine?
vesicular exanthema
thought to be eradicated worldwide
171
What are rhabdoviruses?
enveloped, single-stranded, negative-sense RNA viruses
172
What are the genera of Rhabdoviridae that are most important to veterinary dermatology?
Lyssavirus
- rabies
Vesiculovirus
- vesicular stomatitis
173
What is vesicular stomatitis?
infectious viral disease of horses, cattle, swine, and humans
- zoonotic and REPORTABLE
caused by Vesiculovirus (a rhabdovirus)
enzootic in North, Central, and South America
- has multiple serotypes
transmission is unclear but involves insects, plants, aerosols, and secretions
- Culicoides spp., Simulium spp., sand flies (Lutzomyia)
174
What are the clinical signs of vesicular stomatitis?
Ptyalism
Vesicles/erosions/ulcers in oral cavity, lips
- can affect other locations (esp coronary bands in horses)
- can cause head edema in horses
- frequent affects teats in cattle
Usually self-limiting and resolves in 10-14 days
- reinfection can occur after a second exposure
175
What transmits African horse sickness, what type of virus is it, and what cutaneous lesions can it cause?
Culicoides spp. gnats
orbivirus (nine serotypes) of the Reoviridae family
can have facial edema
176
What is hamster polyomavirus (Mesocricetus auratus polyomavirus 1)?
unenveloped double-stranded DNA virus
cause of epithelioma in Syrian hamsters
177
What is psittacine beak and feather disease (PBFD)?
caused by a circovirus
seen in African Grey Parrots, Lovebirds and Budgerigar
acute form is common
- immunosuppression--> death
chronic form can cause feather color change, lack of down, and dystrophic beak/nails
PCR from feather and quarantine for 60-90 days then retest
- if still positive will probably always be so remove from collection
178
What is avian polyoma virus?
A papillomavirus in Budgerigars
- sudden death if <15 days
- can cause "French molt" in older birds
PCR and if positive quarantined for 4-6 weeks and retest
- if still positive, will always be so remove from collection
179
What transmits Bluetongue (Orbivirus) in cattle, goats, sheep and what are the clinical signs?
Culicoides spp.
Fever, stiffness, lameness, and reluctance to move
A swollen face is a classic sign
- may have ulcers and crusts
- tongue may be cyanotic
dark red to purple band in the skin just above the coronet
180
What does Pestivirus cause in sheep?
Border disease (“hairy shakers”)
neonatal neurological dysfunction
large, long primary hairs and wool fibers +/- abnormal pigmentation
181
What cutaneous signs can be seen with equine viral arteritis?
Edema of distal limbs, scrotum, prepuce, ventrum, around eyes
- occ papular to urticarial eruption
Due to vasculitis from viral antigen in the media of the arteries
182
What does BPV1 cause in cattle?
typical fibropapillomas on the teats & penis
usually in animals <2 yr
often have spontaneous regression in 1-2 mo
183
What does BPV2 cause in cattle?
typical fibropapillomas on on the head, neck, dewlap, shoulder
- occasionally legs & teats
usually in animals <2 yr
often have spontaneous regression in 1-2 mo
184
What does BPV3 cause in cattle?
atypical warts in all ages
anywhere on the body (including teats)
spontaneous regression rare
185
What does BPV5 cause in cattle?
rice grain warts on teats
- Small, white, elongated, hyperkeratotic
affects all ages
does not spontaneously regress
186
What does BPV6 cause in cattle?
Non-pedunculated, conical to branch-like papillomas on teats
affects all ages
does not spontaneously regress
187
What are some clinical signs of rabies in goats?
intense, localized, unilateral pruritus
- with licking, chewing, rubbing, and kicking at affected area
aggression, continuous bleating, incoordination, and paralysis
188
What is inclusion body disease?
thought to be caused by an arenavirus
Associated with dysecdysis
