Chicken Pox (Shingles)

Varicella (chickenpox)
Herpes Zoster (shingles)

viral skin infection--> latent sensory neuron infection

chickenpox

Shingles

Herpes Zoster

Varicella

*Varicella-zoster virus (VCV)
*Human herpesvirus 3 (HHV-3)

*enveloped
*genome double stranded DNA
*produces latent infections
*targets sensory neurons

*R: human
*POI: respiratory systsem
MOT: aerosol, mother to fetus

10-21 days (2-3 wks)

*Virus enters and replicates in the respiratory tract and spreads to lymph nodes, blood stream, and skin

*Viral replication in skin results in vesicular lesions that spread to sensory neurons

Viral genome enters nucleus in dorsal root ganglion and remains dormant

*nucleus in dorsal root root ganlion

*resumes in adulthood and produces skin rash in regions of nerve fiber innervation

*fever
*fatigue
*vesicular rash (3-4 dys)

3-4 dys

*3-4 dys
*primarly face, throat, lower back
*less frequent in chest and shoulders
*vesicles fill with pus, rupture, and form scabs

*after age 50
*latent infection
*localized to skin innervated by infected senory neurons

*hypersensitivity
*pain
*vesicular rash

*secondary infections
*pneumonia
*Reyes syndrome (leads to swelling of brain and liver)

*encephalitis
*pneumonia
*mortaility rare for varicella
*shingles (incidence 1 and 3)

*necrosis
*persistent hypersentivitiy (lasts months)
*posttherpetic neuralgia (burning or stinging)
*chronic pain (indefinite)
*Ramsay Hunt (face nerves paralysis)

Vaccination

*Varicella (MMRV) first dose 12-15 months, booster 4-6 yrs
*Zoster (50-90% effective), shingrix after age 50, need two doses 2-6 months apart

*acyclovir
*antihistamine
*analgesics