Virology 5: DNA Viruses 2 Flashcards
Where do parvoviruses replicate? What do the cells that they are replicating in have do be doing?
Nucleus
Cells must be rapidly dividing
For parvoviruses to replicate, they must be in the ______ of ______ dividing cells. What are examples of these cells in which they replicate best?
Nucleus
Rapidly
Ex. crypt epithelial, leukocytes, developing fetus
When parvovirus replicates what does it form?
intranuclear inclusion bodies
True or False - Parvoviruses are stable in environment
true
Does parvovirus require direct contact with infected animals to be transmitted? Why?
Does not
Stable in environment
What is key to limiting transmission of Parvovirus to healthy animals? Why?
biosecurity
resistant to heat, solvents, disinfectants, pH changes
What is the typical size of Parvovirus?
18-26 nm
In Parvo, how is DNA converted from ss DNA to ds DNA?
By host DNA polymerase
Canine parvovirus, mink enteric virus, and raccoon parvovirus are host-range mutants of what virus?
Feline panleukopenia virus
Feline panleukopenia are ______ in unvaccinated cats.
endemic
Feline Panleukopenia primarily occurs in what age group of cats?
weaned kittens after maternal antibody wanes
What type of pattern is seen with Feline Panleukopenia? Why?
Seasonal due to relation to the birth of kittens
In Panleukopenia, what is the result of transplacental infection?
fetal death (abortion)
cerebellar hypoplasia
Explain how/where the Feline Panleukopenia virus sheds
through feces resulting in contaminated environments
What is the predominant transmission of Feline Panleukopenia?
inhalation and ingestion
Where is viral replication of Feline Panleukopenia?
oropharynx and regional lymph nodes
In parvovirus, viremia develops in ___ hours and the virus infects ______ cells such as ….?
24 hours
mitotically active
intestinal crypts, bone marrow, thymus, lymph node, spleen
In Feline Panleukopenia virus, what does destruction of infected cells result in
villous atrophy and panleukopenia
What are the main clinical signs of Feline Panleukopenia?
depression, vomiting, diarrhea, fetal death, intention tremors due to cerebellar ataxia
In Feline Panleukopenia, what does death occur secondary to?
dehydration and secondary infections
True or False: Canine parvovirus has high mortality and morbidity
true
Until adults developed immunity to Canine Parvovirus, what did pups infected in utero die from?
myocarditis and heart failure
Since adults developed immunity to Canine Parvovirus, what disease is most commonly seen and in what age?
acute enteric disease in dogs between weaning and 6 months of age
Which of the Parvoviruses continue to mutate with new variants emerging
Canine Parvovirus
How is Canine parvovirus transmitted? How is that different than the transmission of Feline Panleukopenia?
CPV is transmitted through ingestion whereas Feline Panleuk is transmitted through inhalation and ingestion
While Feline Panleuk virally replicates in the oropharynx and the _______, CPV virally replicates in the oropharynx and the ______
regional lymph nodes
Peyer’s patches
Destruction of infected cells from CPV results in villous atrophy as does Feline Panleuk however destruction of cells from Feline Panleuk also causes ______ whereas CPV causes
panleukopenia
immune suppression
What are the clinical signs of CPV and how are they similar to Feline Panleukopenia?
depression, vomiting, bloody diarrhea, and the difference is fetal death through myocardial necrosis - panleuk has intention tremors from cerebellar ataxia
In Feline Panleukopenia death occurs secondary to dehydration and secondary infections. What does death occur secondary to in CPV
Dehydration and endotoxemia
What is the main issue with Porcine Parvovirus?
reproductive failure
While sows are immune to porcine parvovirus in endemic farms, gilts are not. When might they be susceptible?
During mating and pregnancy
In porcine parvovirus, when does transplacental infection occur?
10-14 days after infection
In porcine parvovirus, when does damage to the fetus usually occur during gestation?
Before 70 days - before fetus develops immunity
In Porcine Parvovirus, what determines the outcome of a fetus?
Age
In the case of Porcine Parvovirus, explain how the age will effect the outcome. What will the outcome be if embryos are infected, infection before day 70 and after day 70. What is the mnemonic to remember this?
Infected embryos = resorption and infertility
Before day 70 = still birth or mummification
After day 70 = pigs are born alive and healthy
Stillbirth Mummification Early embryonic Death Infertility
Which species is parvovirus primarily enteric?
canine and feline
In which species will there be some fetal death and abortion?
canine and feline
Which species is more likely to have panleukopenia?
feline
In utero infection in cats can result in ________
cerebellar hypoplasia
Which species has primarily reproductive issues associated with parvovirus?
porcine
Which species has SMEDI syndrome?
Porcine
Why can different piglets from the same sow have different outcomes?
Each fetus has own placenta
Unlike DNA viruses, which virus replicates in the cytoplasm?
poxvirus
Instead of intranuclear inclusions what do poxviruses form?
intracytoplasmic inclusions
Which virus is the largest virus that cause disease in domestic animals?
Poxviruses
Are poxviruses enveloped or non-enveloped? Double stranded or single stranded?
enveloped, double stranded
In what conditions are poxviruses stable?
Dry conditions
What are 3 ways in which poxviruses can be transmitted?
aerosol
direct
mechanical (insects)
What does infection of poxviruses usually result in? Why?
Raised skin lesions that progress into scabs due to viral proteins (epidermal growth factor) released leading to epidermal proliferation
In poxvirus, endothelial infection results in ______
vasculitis
In poxvirus, generalized infection results in cell-associated viremia. Explain systematic infection vs local infection
systemic - results in life long immunity
localized - develop transient immunity and recurrence is possible
What does Capripox cause?
generalized infection and characteristic skin lesions
True or False: Capripox has been eradicated in the US so it is considered a foreign animal/reportable disease
True
What are the animals affected by Capripox? What does it cause?
sheep and goat
causes lumpy skin dx in cattle
What are the 3 types of avipox?
fowl
pigeon
turkey
What species does fowl pox affect?
chickens and turkeys
What does Fowl pox cause
lesions on the head and oral mm
What is Fowl pox transmitted by?
biting arthropods
What does suipoxvirus cause and what is it transmitted by?
causes mild skin dx
transmitted by pig louse
What virus is transmittable to humans?
parapoxvirus
What are the 3 types of parapoxviruses?
orf
bovine papular stomatitis
pseudocowpox
What species is affected by:
-Orf
-Bovine papular stomatitis
-pseudocowpox
-young sheep
-young calves
-cows
Where are lesions found in orf parapoxvirus?
around muzzle and lips
Where are lesions found in bovine papular stomatitis?
muzzle, tongue, esophagus
Where are lesions found in pseudocowpox?
on teat
What virus causes milker’s nodules in people?
pseudocowpox
What are the two types of leporipoxviruses?
rabbit myxoma virus
squirrel fibroma virus
What species is the natural host for rabbit myxoma virus?
cottontail rabbits
Which type of rabbits develop severe dx in response to rabbit myxoma virus? Which develop mild disease?
mild - cottontail
severe - european
European rabbits develop severe disease from rabbit myxoma virus what are the clinical signs?
swelling of facial and periocular tissues
What species is affected by Squirrel fibroma virus and what does it cause?
fibromas in squirrels
Which virus results in epithelial proliferation and vasculitis?
poxvirus
Which virus are considered foreign animal diseases?
capripoxviruses
Which virus infects fibroblasts leading to fibroblast proliferation?
leporipoxviruses
Which viruses are considered host specific?
poxviruses
Most disease is cutaneous but systemic infection can occur especially in which virus?
capripoxviruses
