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=Introduction=
 
=Introduction=
 
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Poxviruses are among the most easily recognized of all viruses, owing to the lesion by which they have gained their name.  Once inside cell, proliferation then lysis, giving way to a characteristic pock with a necrotic center.  Poxviruses have risen to fame both for their ability to be eradicated (small pox) as well as their use in fighting other viruses (canarypox vaccines).
    
=Morphology=
 
=Morphology=
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*Non-structural proteins:
 
*Non-structural proteins:
 
**Viral epidermal growth factor, which stimulates cell growth causing the raised edge of pustule
 
**Viral epidermal growth factor, which stimulates cell growth causing the raised edge of pustule
**Viral tumor necrosis factor, which is non-functioning and acts as an anti-inflammatory by competing with TNF-<alpha>
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**Viral tumor necrosis factor, which is non-functioning and acts as an anti-inflammatory by competing with TNF-alpha
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**Viral IL-10, which reduces the Th-1 cell mediated response
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=Therapeutic Use=
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Recombinant Vaccines
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*Poxviruses can be used as heat-stable vectors for vaccines against other viruses
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*Grown in host cell lines or on the surface of chick chorioallantoic membranes in ovo (primordial ectoderm)
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*This was first accomplished by the recombination of cowpox and variola (smallpox) in the creation of the smallpox vaccine (vaccinia)
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*More recently, the French used this technique in the creation of the oral rabies vaccine used among the wild fox population:
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**Recombinant virus inserts a plasmid encoding rabies gene in place of thymidine kinase gene
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*Canarypox vaccines now exist for [[Feline Leukemia Virus (FeLV)|FeLV]] and [[Rabies]]
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**Undergoes a single cycle of replication without producing infectious virus in mammals
    
=Virulence and Pathogenesis=
 
=Virulence and Pathogenesis=
*Once inside cell, proliferation then lysis, giving way to a characteristic pock with a necrotic center
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*Primary replication in abraded squamous epithelium
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*Viremia followed by multiple epidermal infections
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*Ballooning then necrosis (hydropic degeneration) of epidermal cells
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*Concurrent proliferation or adjacent epidermis (GF driven), creating more cells for the virus to infect
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*All three result in classical sequence of lesions:
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**Papule (proliferation)
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**Vesicle (fluid filled)
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**Pustule (lesion breaks)
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**Scab formation (healing begins)
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*Pock center can succumb to secondary infection
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*Resolution in 3-4 weeks
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*Some poxviruses can spread to the upper respiratory tract or viscera, causing more serious pathology
    
=Epidemiology=
 
=Epidemiology=
 
*Spread quickly in unhygienic circumstances
 
*Spread quickly in unhygienic circumstances
 
*Can survive for years in dust
 
*Can survive for years in dust
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=Diagnosis=
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*Clinical signs
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*Histology
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*Electron microscopy
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*PCR, IIF
    
=Types and Subtypes=
 
=Types and Subtypes=
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*[[Cow pox]], which also causes cat pox
 
*[[Cow pox]], which also causes cat pox
 
*Small pox (variola)
 
*Small pox (variola)
*Orf
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*[[Orf]]
 
*Seal pox
 
*Seal pox
 
*Pig pox
 
*Pig pox
*Sheep pox (exotic to EU)
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*Sheep/Goat pox (exotic to EU)
*Goat pox (exotic to EU)
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*[[Myxomatosis]]
*Myxomatosis
   
*Fowl pox
 
*Fowl pox
 
*Pigeon pox
 
*Pigeon pox
 
*Canary pox
 
*Canary pox
*Ectromelia (mice)
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*[[Ectromelia]]
 
*Camel pox
 
*Camel pox
 
*Monkey pox
 
*Monkey pox
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=Diagnosis=
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=Control=
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==Introduction==
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==Orthopoxviruses==
      
==Parapoxviruses==
 
==Parapoxviruses==
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