DNA enveloped viruses Flashcards
the herpes virus family is what type of nucleic acid?
double stranded DNA
what 3 characteristics determine the herpes family biology?
1) dsDNA
2) Icosahedral capsid
3) enveloped
all herpes viruses encode this protein first in order to replicate.
reverse transcriptase
what kind of infections does herpes viruses (all) cause?
lytic, persistent and latent infections
what are the two ways the herpes virus family replicates during infection?
1) actively
2) latent
in an active infection, what causes the symptoms?
cell lysis and cell mediated immunity
what cell mediated immune response cell will lead to symptoms seen in active infection?
natural killer cells
active infection will cause what cellular changes in the infected cell?
syncytia and inclusion body formation
What herpes family viruses (3) will remain latent in neurons?
herpes simplex virus 1
herpes simplex virus 2
varicella
what herpes family viruses will remain latent in hematopoietic stem cells?
cytomegalovirus
human herpes virus 6
what 2 herpes family viruses will remain latent in B cells?
1) epstein-bar virus
2) kaposi sarcoma
against what herpes family viruses do we have an inherent immunity? (antibodies against)
human herpes virus 6 and human herpes virus 7
how is herpes simple virus 1 spread?
through direct contact of fluid
mixing and matching of mucous membranes
how does varicella spread?
aerosol and direct contact with fluid
how does CMV spread?
aerosol
sexual contact
parental transmission
what is the biology of the herpes simplex virus?
it is an enveloped double stranded DNA virus
what protein does herpes simplex virus always have?
DNA polymerase
what cells will herpes simplex virus 1 target to remain latent?
trigeminal ganglia
what cells will herpes simplex virus 2 target?
sacral ganglia
what clinical presentation must be present to diagnose herpes simplex virus 1?
fever
painful vesicular lesions (cold sores)
herpetic keratitis
herpetic whitlow
herpetic gladiatorum
how is the diagnosis of herpes simplex virus confirmed?
histological finding- cowdry type A intranuclear eosinophilic inclusion
syncytia
how do you treat herpes simplex virus?
acyclovir
what is the primary receptor and on what cell for the herpes simplex virus 1?
heparin is the receptor on mucosa-epithelial cells
what is the secondary effect of herpes simplex virus 1?
virus replicates in trigeminal nerve
what cell does herpes simplex virus 2 attack during the active infection?
epithelial cells
where does herpes simplex virus 2 remain latent?
sacral ganglion
what triggers recurrent infection of herpes simplex 1 and 2?
reduced immunity
what two components of immunity will help maintain herpes simplex 1 and 2 latent?
INF-alpha
Th 1 cells
what 3 immune cells help control herpes simplex virus during the active infection?
NK cells
Th 1 cells
CTL’s
what will reduce the flare up of herpes simplex virus 1 and 2?
memory CTL’s
what type of herpes will cause this? what is this called?

herpes simplex virus 1
herpetic vesicular lesion
what is herpes labialis?
its a cold sore in the mouth or lips that presents without fever
what virus causes herpes pharyingitis?
herpes simplex
what is a rare complication of herpes simplex?
herpes meningo-encephalitis
what risk does meningo-encephalitis have?
high risk of death
what will be seen in meningo-encephalitis?
temporal lobe destruction
how do you confirm meningo-encephalitis caused by herpes simplex?
erythrocytes in the CSF
what is herpetic keratitis caused by?
herpes simplex 1
what is very important about herpetic keratitis from herpes simplex 1?
it is the most common cause of infectious corneal blindness
how many eyes will be affected by herpetic keratitis from herpes simplex 1?
1 eye
what is seen in herpetic keratitis by herpes simplex 1?
permanent scarring of cornea
blindness
where will herpes simplex 2 lesions occur in the body?
will be seen genitally
what is this?

herpes simplex 2
genital lesions
what is this?

herpes simplex 2
genital lesions
what type of herpes simplex will neonates contract?
herpes simplex type 2
how will neonate contract herpes simplex type 2?
by being born vaginally with HSV 2 positive mom
what is this?

herpetic whitlow
what is this?

herpes gladiatorum
where does herpetic whitlow occur?
in the finger
how does herpetic whitelow happen?
when someone has a cut and touches a person with herpes simples virus
where does herpes gladiatorum happen in the body?
around the body
who most often gets herpes gladiatorum caused by herpes simplex?
wrestlers or rugby players
herpes simplex can cause this is children
eczema herpeticum
when do kids acquire eczema herpeticum?
what causes it to spread?
when kids already have active eczema
the very eczema causes the spread
what cells does varicella target?
respiratory epithelial cells
what cells does varicella use to remain latent?
nerve cells
what cells does varicella use to spread throughout the body?
T cells
what cells does varicella use for lytic infection?
skin epithelial cells
what is the biology of varicella zoster?
enveloped double stranded DNA
what protein does varicella zoster have?
DNA polymerase
how do you treat vericella zoster?
acyclovir
what cells does varicella zoster target?
epithelial cells
what cells does varicella zoster use to remain latent?
in nerves of dorsal ganglia
what prevention can be taken against varicella zoster?
live attenuated vaccine
how is a diagnosis of varicella zoster confirmed?
checking histologically for Cowdry Type A intranuclear inclusions
also syncytia
what is the clinical presentation of varicella zoster?
fever
respiratory symptoms with painful vesicular lesion
what is the primary type of infection that happens with varicella zoster?
chicken pox
how do you identify chicken pox?
it is asymptomatic pruritic rash
vesicular lesions from the trunk to the scalp (distinct)
what is the secondary type of infection that varicella zoster causes?
shingles
how do you identify shingles?
vesicular lesions in the form of a belt that are extremely painful
chicken pox will occur on children or adults?
children
shingles will occur on children or adults?
adults
how does chicken pox spread?
how infectious is it?
through aerosol or direct contact
highly infectious
why does shingles occur?
it is reactivation of the varicella virus due to immunosuppresion
where does shingles rash occur?
in the trunk
why is shingles rash painful?
due to nerve damage
what cell does varicella use to spread throughout the body?
T cells
does varicella have a viremia stage?
yes
what virus causes this?

chicken pox
what virus causes this?

herpes zoster “shingles”
what happens if you have varicella zoster and are immunocompromised?
Reye-syndrome
post-herpetic neuralgia
Ramsay-Hunt syndrome
what procedure detects syncytia multinucleated giant cells?
Tzanck smear
what is seen here?

syncytia
inclusion bodie with a halo are what type of inclusion bodies?
cowdry type A