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Flashcards in DNA Viruses Deck (15):
1

DNA viruses

what ones?

are dsDNA viruses except?

have linear genomes except?

are icosahedral except?

replicate in nucleus except?

Hepadna, Herpes, Adeno, Pox, Papilloma, Parvo, Polyoma

parvo (ssDNA)

papilloma & polyoma (complete, supercoiled)
hepadna (incomplete, circular)

pox - complex

pox (carries DNA dependent RNA polymerase)

2

Naked viruses

DNA?
RNA?
other?

DNA:
adeno, papilloma, parvo, polyoma

RNA:
calici, picorno, reo

Hepevirus

3

Poxvirus

p/w

linear, dsDNA, complex, replicates outside nucleus

smallpox - now vaccine
cowpox - "milkmaid blisters"
mollucum contagiosum - flesh color papule w/ central umbilication

4

Hepadna virus

incomplete circular dsDNA, has rt

actue vs chronic HBV

5

Adenovirus

non-encapsulated, linear dsDNA virus

p/w febrile pharyngitis, acute hemorrhagic cystitis, PNA, conjuntivitis, gastroenteritis, myocarditis

6

Papillomavirus

non-encapsulated supercoild dsDNA virus

1,2,6,11 - condylomata accumata
16,18 - CIN, cervical CA

7

Polyomavirus

JC & BK virus p/w

non-encapsulated supercoiled dsDNA virus

JC virus - p/w progressive multifocal leukeoencephalopathy in HIV

BK virus - target kidneys in transplant pts

8

Parvovirus
receptor

fetus
children
adults
sickle cell patients

non-encapsulated ssDNA virus; P antigen on RBC

hydrops fetalis

fifths disease: slapped cheeks/erythema infectiosum

pure red cell aplasia & RA like joint sx

aplastic crisis

9

HSV1

tranmission
p/w

w/u

enveloped linear dsDNA

respiratory, saliva
gingivostomatitis, keratoconjunctivitis, herpetic whitlow on finger, erythema multiforme, herpes labialis, temporal lobe encephalitis

more commonly latent in trigeminal ganglia
intranuclear eosinophilic cowdry A inclusions

Tzanck test - multinucleated giant cell in open vesicle
CSF PCR for herpes encephalitis
viral cx for skin/genetalia

10

HSV2

tranmission
p/w

enveloped linear dsDNA

sexual contact, perinatal

herpes genitalis, neonatal herpes

more commonly latent in sacral ganglia
intranuclear eosinophilic cowdry A inclusions

11

VZV (HHV-3)

tranmission
p/w
inclusions

enveloped linear dsDNA

respiratory secretions

chicken pox, shingles, PNA, encephalitis

intranuclear eosinophilic cowdry A inclusions

12

EBV (HHV-4)

receptor
tranmission
p/w mononucleosis

a/w

if use amoxacillin

enveloped linear dsDNA

respiratory secretions, saliva; infect b cells via CD21
=> atypical lymphocytes (reactive cytotoxic T cells)

mononucleosis
= fever, HSM, pharyngitis, LAD

a/w burkitt lymphoma, nasopharyngeal carcinoma, lymphoproliferative dx in transplant pts

amoxacillin => maculopapular rash



13

CMV (HHV-5)

receptor
tranmission

p/w adult - immunocompetent
p/w adult - immunocompromised
p/w congenital

cells look like

remains latent where?

enveloped linear dsDNA; integrins (heparin sulfate)

saliva, urine transplant, sexual, congenital infusion

p/w adult - immunocompetent: mononucleosis w/ -monospot test
p/w adult - immunocompromised: PNA, esophogitis, AIDs, retinitis (hemorrhage, vision loss, cotton wool exudates)
p/w congenital - sensorineural deafness, chorioretinitis, periventricular plaques, HSM & jaundice, "blueberry muffin" rash

owl eye intranuclear inclusions

latent in mononuclear cells


14

HHV-6/7

tranmission
p/w roseola

enveloped linear dsDNA

saliva

roseola infantum/exanthem subitum (fever first, rash later)
= high fever for several days followed by diffuse macular rash (fever can cause seizures)

15

HHV-8

tranmission
p/w Kaposi sarcoma

enveloped linear dsDNA

sexual contact

kaposi sarcoma = neoplasm of endothelial cells
dark, violacious plaques or nodules
can effect GI tract and lugs as well