Infectious Disease

Shingles (Herpes Zoster)

Shingles is reactivation of latent varicella-zoster virus in a sensory ganglion, usually causing a painful unilateral dermatomal rash; treat eligible patients promptly, recognise ophthalmic, neurological and disseminated disease, manage post-herpetic neuralgia, and offer current Shingrix vaccination to eligible cohorts.

In a nutshell

Shingles is reactivation of latent varicella-zoster virus causing a painful unilateral dermatomal vesicular rash. Diagnose clinically in typical cases and start oral aciclovir promptly when age, severity, location, immune status or risk of complications makes treatment indicated. Ophthalmic zoster, red or painful eye, visual change, Ramsay Hunt syndrome, meningitis, myelitis, disseminated disease and severe immunosuppression need urgent specialist care. Treat post-herpetic neuralgia as neuropathic pain, protect vulnerable contacts while lesions are weeping and check current Shingrix eligibility.

Classic presentation

An older adult develops burning unilateral thoracic pain followed by grouped vesicles that stop at the midline; a forehead or nose rash, red eye, visual change or facial palsy changes the urgency.

Key points

Shingles is VZV reactivation in a sensory ganglion; a typical painful dermatomal vesicular rash is a clinical diagnosis.
Consider oral antiviral therapy within 72 hours for people over 50 or with moderate/severe pain or rash, non-truncal disease, ophthalmic or Ramsay Hunt disease, eczema or immunocompromise; check BNF and local pathways.
Ophthalmic zoster and eye symptoms need urgent specialist assessment; Hutchinson's sign increases ocular risk but its absence does not exclude eye disease.
Disseminated or severe immunocompromised disease may need admission and intravenous aciclovir.
Post-herpetic neuralgia is persistent neuropathic pain after the rash and needs a neuropathic-pain pathway.
Shingrix is a non-live two-dose vaccine for eligible cohorts, including severely immunosuppressed adults from 18 years under the current programme.

First-line investigation

Clinical diagnosis; use lesion VZV PCR for atypical, disseminated, recurrent or immunocompromised disease and assess the affected eye, facial nerve or CNS urgently when indicated.

Management

Identify eye, neurological and disseminated emergencies

Arrange urgent eye assessment for ophthalmic zoster with a red or painful eye, photophobia, visual change, floaters, swollen eyelids or Hutchinson's sign.^3,5,6
Admit or seek urgent specialist care for Ramsay Hunt syndrome, meningitis, encephalitis, myelitis, disseminated zoster, severe immunosuppression, sepsis or inability to take oral treatment.^2,11,8,7

Confirm the diagnosis and host risk

Diagnose a typical unilateral dermatomal vesicular rash clinically; use lesion VZV PCR when atypical, recurrent, disseminated, immunocompromised or when HSV is a serious alternative.^1,3,2
Review immune status and consider HIV testing for young, recurrent, severe, multidermatomal or disseminated zoster because herpes zoster is an HIV indicator condition.^9,10,1

Treat early and control pain

Consider oral aciclovir within 72 hours for age over 50 years or moderate/severe, non-truncal, ophthalmic, Ramsay Hunt, eczema-associated or immunocompromised disease; check BNF for renal-adjusted prescribing.^1,11,13,12
Give analgesia for acute pain and move to a neuropathic-pain pathway if pain persists after the rash heals; do not use repeated antiviral courses for established neuralgia alone.^3,1,14

Use specialist pathways for high-risk disease

Treat ophthalmic zoster systemically and arrange specialist eye review; protect the cornea in facial palsy and use ocular steroids only under ophthalmology direction.^5,6,12
Use hospital-led intravenous aciclovir and organ monitoring for disseminated or severe immunocompromised infection, with renal function and hydration monitored.^2,8,12

Prevent spread and prevent recurrence

Keep lesions clean, dry and covered where practical; avoid susceptible pregnant people, neonates and immunocompromised contacts until lesions crust, and use the UKHSA PEP pathway after significant exposure.^3,8
After recovery, check current Shingrix eligibility: severely immunosuppressed adults from 18 years and eligible immunocompetent older adults receive the current non-live two-dose schedule.^2,4,15

Exam traps

Vesicles on the nose tip, side or root suggest nasociliary involvement, but absence of Hutchinson's sign does not rule out ocular disease.
A person with shingles can transmit chickenpox to a susceptible contact, not shingles.
Antivirals are most useful early but can still be considered later when vesicles continue or complication risk is high.
Ramsay Hunt syndrome is facial nerve zoster with ear pain or vesicles, hearing change or vertigo and needs urgent specialist assessment.
Atypical or disseminated zoster in a young adult should prompt assessment for immunosuppression and HIV testing where appropriate.
Post-herpetic neuralgia is treated as neuropathic pain; do not keep repeating antiviral courses once the active episode has ended.

Illustrations

Dermatomal distribution of shinglesA diagram of reactivation in a single sensory ganglion producing a unilateral dermatomal vesicular rash that stops at the midline.Fisle, Wikimedia Commons · CC-BY-SA-3.0

Herpes zoster ophthalmicus and Hutchinson's signA clinical illustration of ophthalmic-division zoster with vesicles on the tip of the nose indicating nasociliary involvement and increased risk of ocular disease.User:Milorad Dimic MD, Wikimedia Commons · CC-BY-SA-3.0

Key sources

This page is exam revision material, not medical advice, and must not be used for patient care. Always check drug doses against the BNF and current guidance. Full disclaimer.