Virology: Herpes Virus

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