Virology: Herpes Virus

Herpes Virus

ds DNA virus, non-segmented
enveloped
chronic infection
-latency
-reactivation linked to immunosuppression
species restricted
-human only
types: alpha, beta, gamma

Alpha

herpes simplex virus type 1 (HSV-1)
herpes simplex virus type 2 (HSV-2)
Varicella-zoster virus (VZV, chicken pox)

Beta

cytomegalovirus

Gamma

Epstein-Barr Virus (EBV)
Kaposi sarcoma virus (HHV-8)

HSV-1: cells

Target cells: mucoepitheal cells
-predominantly facial, can be genital
Latency cell: neuron

HSV-1: transmission

contact with shedding mucoepitheal cells
-does not require sores

HSV-1: disease

primary: lots of sores
latency: nothing-ish
reactivation: few sores

HSV-1: treatment

viremia: no
vaccine: no
drugs: yes
-prevent replication, does not clear infection

HSV-2: cells

Target cells: mucoepitheal cells
-predominantly genital, can be facial or anal
Latency cell: neuron

HSV-2: disease

sores in genitals and other places
can be ocular infection

HSV-2: transmission

contact with shedding mucoepitheal cells
-sex
-vaginal birth (eyes with the infected cells, go to brain)
-does not require sores

HSV-2: treatment

viremia: no
vaccine: no
drugs: yes
-prevent replication, does not clear infection

HSV-2: prevention

safe sex, prevent exposure during birth

VZV: cells

Initial target cells: respiratory epithelial cells
-secondary sites: respiratory tract, skin
Latency cell: neuron
-reactivation: shingles

VZV: transmission

primary: respiratory
secondary: contact with shedding from skin

VZV: disease

chicken pox, shingles
sores on skin
itchy

VZV: treatment

viremia: yes
vaccine: yes (live-attenuated)
drugs: yes
-prevent replication, does not clear infection

CMV: cells

Target cells: monocytes, granulocytes, lymphocytes (cells of the immune system) and epithelial cells
Latency cells: monocytes, myeloid stem cells, others

CMV: transmission

contact with blood, bodily fluids, tissue and organs
-transplacental, breast feeding, organ transplant

CMV: disease

infection: usually asymptomatic carrier
-cytomegalic inclusion disease
-multisite symptomatic disease

CMV: who do we worry about?

infants: developing immune system
immunocompromised w/ AIDS
transplant recipients

CMV: treatment

viremia: no
vaccine: no
drugs: yes
-prevent replication, does not clear infection

CMV: prevention

screening

EBV: cells

Target cells: B cells and epithelial cells
Latency cells: B cells

EBV: transmission

primary: saliva (kissing)
secondary: asymptomatic shedding

EBV: disease

mono is key symptom in acute phase
later on --> get lymphocytes

EBV: treatment

viremia: no
vaccine: no
drugs: no

EBV: prevention

avoid contaminated saliva

HHV-8: cells

Target cells: lymphocytes
Latency cells: B-cells

HHV-8: transmission

primary: saliva (kissing), genital fluid
secondary: asymptomatic shedding

HHV-8: disease

normally asymptomatic
immunocompromised: Kaposi sarcoma

HHV-8: treatment

viremia: no
vaccine: no
drugs: no

HHV-8: prevention

avoid contaminated saliva, safe sex