Herpes Flashcards
Classify the herpesviruses
family: herpesviridae. enveloped. dsDNA icosahedral capsid
How many herpesviruses are there?
8
HSV-1 does what?
cold sores
HSV-2 does what?
genital herpes
VZV
Chickenpox, zoster
EBV
mono, oral hairy leukoplakia, B cell lymphoma, nasopharyngeal carcinoma
CMV
post transplant infections, retinitis
HHV-6
exanthem subitum or roseola infantum
HHV-7
no associated disease
HHV-8
Kaposi’s Sarcoma
What virus and what is herpetic gingivostomatotis
vesicular lesions on the oral mucous memranes that rupture and leave yellowish-gray ulcers or plaques. usually HSV-1
Herpes labialis
cold sores, fever blisters. vesicles at localized sites in the orofacial area that rupturea nd leave shallow ulcers or dry and form a scab.
genital herpes
HSV2. genital vesiceles that rupture forming ulcers in the genital region
neonatal herpes
infection of the newborn during delivery usually HSV2
herpes keratitis
acute necrotizing viral encephalitis usually HSV1
Describe pathogenesis of HSV
HSV is transmitted by direct contact of mucosal surfaces. Virus infects the epithelial cell and spreads causing primary lesion. Virus encounters sensory neuron ending where it binds and enters. It travels up via retrograde transport to the cell body and just hangs out there in a period of latency expressing LAT. Because there is no protein expression, it is not killed by a CTL response. At a later time, it will travel back down the neuron causing reactivation
What is the prevalence of HSV1
70% in the US. 90% in the developing world
What is the prevalence of HSV2
17% in the US. 50-80% in developing countries
Describe pathogenesis of VZV
VZV is inhaled as respiratory aerosols. Virus replicates in epithelial cells, then leads to the regional lymph nodes and infects T cells. Viremia then occurs in the blood. Leading to infection of liver and spleen. Infected mononuclear cells spreads then to the skin and mucousal membranes leading to pocks. Virus spreads to the dorsal root ganglia establishing latency there. Reactivation will then occur again along the dermatome usually on the body trunk.
Describe pathogenesis of EBV
transmitted by saliva. virus infects pharyngeal epithelial cells where it replicates and is shed in throat and saliva. EBV then infects the B cells (esp. those in the tonsils). EBV gene products stimulate proliferation of random B-cells which is why you can detect via monospot.
What drugs do we use to inhibit HSV
Acyclovir
Is there a vaccine for HSV?
No, but there is one in the pipelines
Is there a vaccine for VZV?
Yes
What actually causes the mono sx
T cell response to EBV
