LEC 10 - Papilloma + Pox Virus Flashcards
With ocular nasal discharge + skin lesions what would be important to sample from?
Lesions Lymph nodes Spleen
What tests should be ran with a animal that has ocularnasal discharge and skin lesions?
C/S
VI
EM
What are the differientials in an animals that has skin lesions + oculonasal discharge?
Tularemia
Plague
Herpes virus
What is the target when trying to make a conclusive diagnosis about which orthovirus an animal has?
Conserved/Degenerate PCR
Target: Hemagglutinin gene
What is the reservior for monkeypox?
Rodents
What diseases are under capripoxviruses?
Sheep/goat pox
Lumpy skin disease
What diseases are under leporioxivirus?
Rabbit Myxoma virus
Types of diseases: Orthopoxvirus
Vaccinia
Coxpox
Types of diseases: Parapoxviruses
ORF
Bovine papular stomatitis
Pseudocowpox
Types of diseases: Avipoxvirus
Fowlpox
What are the reportable poxvirus diseases?
Sheep/goat pox
Lumpy skin disease
Rabbit Myxoma virus
What is the structure of the pox virus?
Barrel/box structure
What is the genome in a pox virus made of?
dsDNA
Is poxvirus enveloped or not?
Yes
How does poxviruses get into the cell?
Fusion/Macropincytosis
Where does the pox virus replicate in the host cell?
Cytoplasm
What is the sequence of events in the poxvirus infection?
Fusion/macropinocytosis
Uncoating + early protein synthesis
Intermediate gene expression + DNA replication in cytoplasm
Late phase gene expression = structural proteins
Viral assembly
Virion
What types of virions do pox viruses make?
Intracellular mature virion
External enveloped virion
What does the intracellular mature pox virion do to the cell?
Lyse the cell no envelope
What are does the external enveloped virion do to the host cell?
Budding so does not harm the host cell immediately
May lyse later one
What is the incubation period for the pox virus?
3 to 5 days
What are the clinical signs of the pox virus?
Skin lesions - vesicles + scabbing
Lesions variably located
Mortality rare but can occur
How does immunity occur to the pox virus?
IFN - directed
Complement cascade
CTL-mediated
How does the pox virus evade the immune system?
Stealth + Mimicry
MHC I + CD4 down regulation + depletion
IFN + TNF receptor homologs
IL-10 homologs
Complement system disruption
What does poxvirus cause in bovine?
Bovine papular stomatitis
What is important to remember when working with a possible BVS case?
Zoonotic potential
What is the disease course of bovine papular stomatitis?
3 weeks
What is the major clinical signs of bovine papular stomatitis?
Oronasal lesions
What are the clinical signs of orf/contagious ecthyma?
Oronasal lesions
How long does it take for contagious ecthyma to run its course/
3 weeks
What is important to remember when working with Contagious ecthyma?
Zoonotic
What body systems are targeted with sheep/goatpox?
Dermal
Pulmonary
What type of prevention is avalible for sheep/goatpox?
MLV
Subunit vaccines
What is the mortality rate with sheep/goatpox?
Greater than 50$
What is the target in lump skin disease?
Endothelium
What is the problem with lumpy skin disease?
> 5% mortality
But great economic loss due to decrease in weight
What type of prevention is used in lumpy skin disease?
MLV, subunit vaccines
What animals are most affected by myxomatosis?
Oryctolagus rabbits (European)
Sylvilagus rabbits ( Cottontails + Jack rabbits) not killed by the virus
What cells are targeted in Myxomatosis?
Lymphocytes
What protection is avalible for myxomatosis?
MLV, non-lethal analog virus
What is the mortality rate with myxomatosis?
25 to 99%
How are pox viruses transmitted?
Aerosol
Vector
Direct contact
Fomites
What is the treatment for poxvirus infection?
Palliative
What are the differientials for dermal neoplasias in a horse?
Equine sarcoid
Squamous cell carcinoma
Granulomas
Solar dermatitis
What is seen upon histology of a dermal neoplasia that is due to equine sarcoids?
Spindle cells in interlacing bundles + whorls
Collagenous matrix
Low-moderarte mitotic rate
What causes equine sarcoids?
Non-conforming bovine papillomavirus (BPV-2) infection
What is the structure of the papilloma virus?
Icosahedral structure
What is the structure of the genome in the papillomavirus?
dsDNA
How does the papillomavirus enter the host cell?
Endocytosis
Where does the papillomavirus replicate?
Nucleus
What is the sequence of the papillomavirus replication?
Endocytosis
Transport to nucleus
Early protein transcription/translation
Late protein transcription/translation
+/- host chromosome integration
What cell type is the papillomavirus endocytosed within?
Basal squamous epithelial cells
What are the clinical signs of papillomavirus?
Proliferative lesions (warts) of the epithelium
Dermis, oral/gastric mucosas, bladder
What is the major characteristic of the life cycle of a papillomavirus?
Lengthy + Variable incubation period
How does the host immune system handle the papillomavirus?
Primarily cell mediated
Since doesn’t go in the blood rely on peripheral immune system
How does the papilloma virus avoid the immune system?
Stealth - no viremia + non-cytolytic
IFN pathway inhibition
What is the treatment for a papillomavirus infection?
Excision
Cryosurgery
Radiation + Chemotherapy
What can happen in dogs with a papillomavirus infection?
Spontaneous regression
What is the structure of the genome of african swine fever?
dsDNA
What is the structure of the african swine fever virus?
Icosahedral, non-enveloped
What is special about the african swine fever virus?
Only known DNA cirus with an arthropod vector (TICKS)
How does african swine fever virus enter the host cell?
Viral endocytosis
Where does the african swine fever virus replicate in the host cell?
Cytoplasm
What is the sequence of events when it comes to the african swine fever virus?
Early gene trasncription + genome replication
Late gene trasncription (structural proteins)
Packaging + membrane budding
What are the peracute signs of african swine fever?
Sudden death
What are the acute signs of african swine fever?
Fever + ADR + Cutaneous hemorrhage
High mortality
What are the subacute symptoms of african swine fever?
Pneumonia
Weight loss
Joint swelling
ADR
Variable mortality