Poxviridae Flashcards
What are the 6 poxviruses we cover?
- Orthopoxvirus
- Parapoxvirus
- Avipoxivurs
- Capripoxvirus
- Leporipoxvirus
- Suipoxvirus
T/F: Poxviruses can be naked or enveloped, pleomorphic, and are usually brick-shaped
True
T/F: Parapoxvirus, in contrast with typical poxviruses, are ovoid and appear to have a crisscross, thread like surface
True
What are two distinct infectious poxvirus particles?
- Intracellular (naked) mature virus (IMV)
2. Extracellular enveloped virus (EEV)
T/F: poxviruses have icosahedral or helical symmetry
False, they have complex symmetry where the virion outer layer encloses a dumbbell-shaped core and two lateral bodies
T/F: poxviruses have a single molecule of linear double stranded DNA
True
Where does replication of poxvirus predominantly, if not exclusively, occur in?
Cytoplasm
T/F: both enveloped and non-enveloped virions are infectious
True
Why are enveloped poxviruses more unique?
Have high environmental stability and remain infectious over a period of several months in an ambient environment
What 3 routes can poxvirus be transmitted between animals?
- Skin (broken skin)
- Resp. routes (aerosol)
- Mechanical (arthropods)
What body system does poxvirus use to gain access to the systemic circulation?
Lymphatic system
What is the order of skin lesions caused by a poxvirus infection?
Macule > Papule > Vesicle > Pustule > Scab > Scar
Ma…Pa…Ve…Pu…Sca
What are two main infections caused by Orthopoxvirus?
- Cowpox
2. Monkeypox
T/F: Cowpox and monkeypox are both zoonotic
True
What is the reservoir host for cowpox?
Rodents
T/F: cowpox can be transmitted though infected milker’s hands or teat cups
True
T/F: With cowpox, papules can appear on teats and udder, leading calves to develop lesions in mouth
True
What is the usual route of transmission for cowpox in cats?
Skin inoculation, through bite or wound
T/F: Rodents are a common reservoir for cowpox in cats
False
What is the primary lesion of cowpox in cats?
Single primary skin lesion on head, neck, or forelimb
T/F: Ulcerative lesions or crusting papular lesions are signs of secondary lesions of cowpox in cats
True
What is the main transmission of cowpox in humans?
Mainly by cat contact, RARELY by rodents or zoo animals
What is the primary transmission route for monkeypox infection in humans?
Direct contact
What is the secondary transmission route of monkeypox in humans?
Human-to-human (close contact)
What are two infections that parapoxviruses cause?
- Pseudocowpox
2. Contagious ecthyma/orf virus
What is the condition that pseudocowpox virus causes in humans called?
Milker’s nodule
What is the primary transmission route of pseudocowpox?
Contaminated milker’s hand, teat cups
What are the acute lesion signs of pseudocowpox?
Erythema > papules > vesicle or pustule > rupture > thick scab > horse shoe shaped ring
What are two ways to Dx pseudocowpox?
- Horseshoe shaped ring like lesion
2. Isolation and detection via Dx lab methods
What is done to the removed scabs of pseudocowpox in order to prevent environmental contamination?
They are burned
Who are the primary hosts of contagious ecthyma/ORF caused by parapoxvirus?
Sheep and goats, usually lambs and kids
What are the order of lesions that contagious ecthyma/orf forms?
Macule > papule > vesicle > pustule > ulcer > scab
What are the CS of contagious ecthyma?
- Lip swelling > spread to muzzle and nostrils > difficulty eating > anorexia and weight loss
- Lesion in feet > lameness
- Lesion in scrotum > infertility
What species can a malignant form of contagious ecthyma be observed?
Sheep
T/F: Vaccines should be used on farms, even if there isn’t a problem with orf/contagious ecthyma
False
T/F: Vaccination of contagious ecthyma/orf offer long lasting immunity
False; ~1-2 years
When should pregnant ewes be vaccinated against contagious ecthyma?
Before lambing
T/F: contagious ecthyma/orf is zoonotic
True
What three disease does capripoxvirus cause?
- Sheep pox
- Goat pox
- Lumpy skin disease of cattle
What is a common route of transmission for sheeppox and goatpox?
Aerosol / resp. route
T/F: Sheeppox is a systemic disease
True
What are the two forms of sheeppox?
Malignant and benign form
T/F: malignant sheeppox is seen in lambs and susceptible nonnative breed while benign sheeppox is seen in adults and resistant breeds
True
T/F: sheeppox is reportable in most countries
True
T/F: killed vaccines offer temporary protection while live attenuated vaccines offer excellent protection lasting over a year against sheeppox
True
T/F: goatpox is not reportable
False, it is reportable
What is the most common transmission route of lumpy skin disease in cattle?
Arthropod vector
What disease does suipoxvirus cause?
Swinepox in pigs
What is an important transmission route of swinepox?
- Pig louse, haematopinus suis
T/F: There is evidence of transplacental infection of swinepox
True
What are the typical pox lesions of swine pox?
Skin lesions
Exudative epidermitis (greasy pig) and secondary bacterial dermatitis
Upper respiratory tract and digestive tract in severe infections
What disease does avipoxvirus cause?
Fowlpox
Want are the 3 Clinical forms of fowlpox?
- Cutaneous dry form (most common)
- Diphtheritic wet form
- Ocular form
Histologically, bollinger and borrel bodies can be seen with what poxvirus?
Avipoxvirus
What is an important fowlpox control method?
Mosquito (and other biting insects) control
What are the two manifestations of ulcerative dermatosis of sheep?
- Lip and leg ulceration
2. Venereal form
What are two tranmission modes of ulcerative dermatosis of sheep?
- Damaged skin
2. Coitus
What are 7 methods to Dx poxviruses?
- CS
- Sampling
- EM
- Histopathology
- Inoculation in embryonated egg (pock lesions)
- ELISA (serological assay)
- PCR
T/F: parapoxviruses multiply in chicken embryo
False
