poxviridae 1 Flashcards
(28 cards)
Poxviridae is
family
Chordopoxvirinae
subfamily
genus groups of Poxviridae
orthopoxvirus
parapoxvirus
avipoxvirus
poxvirus general characteristics
DNA, complex symmetry
pleomorphic, usually brick-shaped (orthopoxvirus) or ovoid shaped (parapoxvirus), large, sometimes enveloped
names of infectious forms of Poxvirus
IMV=intracellular mature virus
EEV=extracellular enveloped virions
EEV has
2 membranes
envelope and inner membrane
extra envelope a consequence of budding
IMV
only an inner membrane, only by disruption of cell to release virus
complex symmetry
outer layer covers dumbbell shaped core with viral DNA, two lateral bodies keep the core in place
genome
single molecule of linear double stranded DNA, cross links join two DNA strands at both ends, many protein are involved in nucleic acid synthesis and vision structural components and also those that counteract host proteins
replication
located in cytoplasm, because has own polymerase, virions are released by budding, cell lysis (most common), or exocytosis
-enveloped versions are more important for spread of virus
special about pox envelopes in EEV
low lipid content-> allows more stability in environment
transmission of pox
skin- open wounds
respiratory- aerosol inhalation
mechanically- arthropod
pathogenesis of immunity
highly epitheliotropic (infect epithelium readily)
- can cause systemic disease in wild birds and animals
- most pox viruses are host specific, yet orthopoxviruses
spread of pox
will get into the body then gains access to the systemic circulation and to other target organs through secondary viremia
pox virus can survive in scabs or other forms including
macule-local inflammation flat red
papule-raised red inflammation invading neighboring tissue
vesicle-microbe invades epithelium, small blister
ulcer-epithelium ruptures, microbes discharged
pox genus: orthopoxvirus
distribution (cowpox)
Europe and Asia
orthopox hosts (cowpox)
cattle, wild and domestic cats, humans, zoo animals
rodents are reservoir
orthopox: cow pox transmission
milkers hand or teat cups
infected farm cats also transmit the disease
rodents are reservoir
cow pox economic importance
lose milk, due to soreness and inconvenience
cow pox clinical findings
incubation 3-7 days, papules on teats, vesicles erupt rapidly
cow pox transmission in cats
inoculation through open wounds or scratches or rodent bites
oro-nasal rote possible
clinical signs cow pox in cats
single primary skin lesion on head neck or forelimb that can form a small scab or abscess
secondary- 7-10 day incubation papules to ulcers to scabs
cowpox in humans transmission
direct contact with cuddly cats
very are from cattle
cowpox in humans clinical signs
hand and face macropapular lesions, enlarged painful local lymph nodes, may report fever vomitting and sore throat
