Synopsis
Distinguish primary varicella from zoster reactivation, recognise ocular, neurological and disseminated disease, treat promptly, and deliver current UK exposure prophylaxis and vaccination.
- Primary VZV causes chickenpox with crops of pruritic lesions at different stages; reactivation causes unilateral dermatomal shingles that usually does not cross the midline.
- Chickenpox spreads by respiratory and lesion contact from about 48 hours before rash until all lesions crust; uncovered or disseminated shingles can also transmit VZV.
- Adults, pregnant people, neonates and immunosuppressed patients have greater risk of pneumonitis, encephalitis and disseminated disease.
Key red flags
Eye pain, photophobia, reduced vision, red eye or vesicles on the forehead or nose needs same-day ophthalmic assessment for sight-threatening zoster.
Forehead, upper-eyelid or nasal lesions with red eye, photophobia, pain or visual change indicate trigeminal involvement.
Investigation priorities
Confirm VZV in atypical, severe, disseminated or epidemiologically important rash.
Management branches
A generalised vesicular rash or disseminated zoster is suspected in a healthcare or shared setting.
- Separate the patient from susceptible pregnant, neonatal and immunosuppressed people and apply airborne plus contact precautions in healthcare.
- Establish rash onset, lesion distribution, immune status, pregnancy, respiratory and neurological symptoms and every significant contact during the infectious interval.
Routine childhood, catch-up, occupational, contact or shingles-vaccine eligibility is reviewed.
Key medicines
Aciclovir for uncomplicated shinglesGive 800 mg orally five times daily for seven days, started ideally within 72 hours of rash onset when treatment criteria are met.
Valaciclovir for uncomplicated shinglesGive 1 g orally three times daily for seven days as a simpler-bioavailability alternative when oral therapy is appropriate.