Virus lives in dorsal root ganglion, reactivates for unknown reasons
Risk Factors
HIV+
Increasing age over 50
Otherwise immunocompromised
Lack of adult vaccination (to prevent Shingles)
Children can be vaccinated to prevent primary infection (presumably will decrease risk shingles)
Symptoms
Burning type pain in dermatomal region for 1-3 d prior to eruption
Then characteristic dermatomal skin eruption, with vesicles appearing over 3-5 days
Resolves over 2-4 weeks
Persistent neuropathic pain can last for months (risk increases with age)
If HIV + and low CD4, tends to persist and recur; also higher risk for more severe and disseminated disease
Ha, confusion, neck stiffness w/meningitis or encephalitis--> rare, typically limited to immunocompromised hosts
Ear pain, peripheral facial nerve palsey with Ramsay-Hunt from CN7 involvement; due to proximity w/CN8, may also have hearing loss, hyperacusis, tinnitus, vertigo
Physical Exam Findings
Vesicles, which appear in a 1-2 (adjacent) dermatomal distribution
Doesn't typically cross mid-line of the body
Can sometimes have bacterial supra-infection (cellulitis)
Infection in eye region (zoster ophthalmicus) presents risk to vision
Ramsay Hunt--> vessicles on ear drum/canal, face, CN7 palsy