Incidence of herpes simplex infection among febrile infants under 3 months of age: evidence from two multisite cohorts

The prevalence of invasive bacterial infection in young febrile infants is estimated at 1%–4%, with the highest rates in those <21 days. 1 UK guidelines recommend screening all febrile neonates for bacterial infection and starting empiric broad-spectrum antibiotics while awaiting results,2–4 but not routine antiviral therapy. However, a recent UK/Ireland prospective surveillance study reported an increased incidence of neonatal herpes simplex virus (HSV) infection of 6.0 per 100 000 live births, with substantial associated morbidity and mortality.5