Synopsis
Recognise genital HSV across first and recurrent episodes, test lesions at the useful moment, treat symptoms promptly, and give practical counselling about recurrence, transmission, relationships and pregnancy.
- Think of genital HSV when pain, dysuria and tender nodes accompany grouped vesicles or shallow erosions; first episodes may also produce fever and substantial malaise.
- A recurrence is usually shorter and more localised, and a patient may recognise tingling or burning before lesions return in the same region.
- Take material from a fresh vesicle or ulcer base for typed HSV NAAT; an HSV blood-antibody result cannot assign the cause of today’s ulcer.
Key red flags
A painful episode accompanied by a palpable bladder or inability to void needs urgent assessment for retention, not advice about dysuria alone.
Perineal numbness, constipation, leg symptoms, severe headache, photophobia, neck stiffness or altered behaviour raises concern for sacral or central nervous-system involvement.
Widespread vesicles, marked constitutional illness, hepatitis, respiratory compromise or shock is an emergency, particularly during pregnancy or major immunosuppression.
Vesicles, conjunctival disease, poor feeding, temperature instability, lethargy or seizures in a neonate with possible exposure requires immediate neonatal assessment and intravenous antiviral treatment.
Suspected first acquisition late in pregnancy needs same-day maternity and sexual-health input because the timing of acquisition drives neonatal risk.
An ulcer that enlarges, becomes hypertrophic or fails to heal despite adherent therapy in advanced HIV requires resampling, resistance work-up and reconsideration of the diagnosis.
A distended bladder, inability to pass urine, constipation, saddle sensory change or leg symptoms during an episode indicates possible sacral nerve-root dysfunction and requires urgent hospital assessment.
Diffuse lesions with encephalopathy, meningism, hepatitis, pneumonitis or sepsis signals disease outside an uncomplicated genital episode and requires syndrome-specific inpatient care.
Possible new maternal infection near birth, active lesions in labour, or illness in an exposed neonate requires immediate maternity or neonatal coordination because management depends on acquisition timing and the infant’s clinical state.
Investigation priorities
Demonstrate HSV in the symptomatic site and distinguish HSV-1 from HSV-2 for prognosis and counselling.
Management branches
A compatible first clinical episode began within five days, or fresh lesions are continuing to appear.
- Sample an active lesion for typed HSV NAAT and offer syphilis, HIV and site-specific STI testing without making treatment conditional on the results.
- Start aciclovir 400 mg orally three times daily for five days.