Description

• Results from reactivation of latent varicella-zoster virus (VZV) (human herpesvirus type 3) infection
• Postherpetic neuralgia (PHN) is defined as pain persisting at least 1 month after rash has healed. The term zoster-associated pain is more clinically useful.
• Herpes zoster ophthalmicus (HZO) is an important complication involving branch of the trigeminal nerve.
• Zoster usually presents as a painful unilateral vesicular eruption with a dermatomal distribution.
• System(s) affected: nervous; integumentary; exocrine
• Synonym(s): shingles

Epidemiology

Incidence

• Incidence increases with age—2/3 of cases occur in adults aged ≥50 years. Incidence is increasing overall as the U.S. population ages.
• Herpes zoster: 4/1,000 person-years
• PHN: 18% in adult patients with herpes zoster; 33% in patients ≥79 years of age
• Individual lifetime risk of 30% in the United States

Prevalence
~1 million new cases of herpes zoster annually in the United States

Pregnancy Considerations
May occur during pregnancy

Geriatric Considerations

• Increased incidence of zoster outbreaks
• Increased incidence of PHN

Pediatric Considerations

• Occurs less frequently in children
• Has been reported in newborns infected in utero

Etiology and Pathophysiology

Reactivation of VZV from dorsal root/cranial nerve ganglia; on reactivation, the virus replicates within neuronal cell bodies, and virions are carried along axons to dermatomal skin zones, causing local inflammation and vesicle formation.

Risk Factors

• Increasing age
• Immunosuppression (malignancy or chemotherapy)
• Physical trauma
• Female
• HIV infection
• Spinal surgery

General Prevention

• Shingrix recombinant herpes zoster vaccination is the preferred vaccine. It is recommended for adults who previously received Zostavax.
• Patients with active zoster may transmit disease-causing varicella virus—typically through direct contact.

Commonly Associated Conditions

Immunocompromised states, HIV infection, posttransplantation, immunosuppressive drugs, and malignancy