Introduction. Neonatal disseminated herpes simplex virus (HSV) infection can cause rapidly progressive multiple organ failure with an 85% mortality if untreated. Early recognition and treatment may improve outcome [N Engl J Med 324(1991)450].

Objectives. (i) To determine the number and presentation of neonates with disseminated HSV admitted to an intensive care unit. (ii) To determine paediatric Specialist Registrar (SpR) awareness of the diagnosis and management of a typical potential case of neonatal disseminated HSV.

Methods. (i) A 10-year review of case notes of neonates admitted to the intensive care unit (ICU) at Great Ormond Street Hospital. (ii) A telephone questionnaire of ‘on-call’ Paediatric SpR's in the London area.

Results. Eight cases of confirmed disseminated HSV infection were identified. All died. Each case followed a similar clinical course with presentation between days 5–9 of life (median day 7). A short prodrome preceded the rapid development of disseminated intravascular coagulopathy (DIC), hepatitis and multiple organ failure. Only three cases received antiviral treatment in the first 24 h after hospital admission. None of the 30 registrars who were interviewed initially considered disseminated HSV in the differential diagnosis of a 7-day-old baby presenting with non-specific signs of sepsis. Only 4/30 referring unit protocols included disseminated HSV in the differential diagnosis of neonatal sepsis.

Conclusions. HSV infection should be considered in the differential diagnosis of the acutely unwell neonate. This condition is rare but well documented in the literature. Effective antiviral therapies exist but are often not started early in the clinical course. Awareness of this condition needs to be increased.