Thanks to the introduction of recent national guidelines for treating herpes simplex virus (HSV) encephalitis, health outcomes have improved. This paper evaluates the health system costs and the health-related quality of life implications of these guidelines.

A sub-analysis of data from a prospective, multi-centre, observational cohort ENCEPH-UK study conducted across 29 hospitals in the UK from 2012 to 2015.

Data for patients aged ≥16 years with a confirmed HSV encephalitis diagnosis admitted for treatment with aciclovir were collected at discharge, 3 and 12 months.

Patient health outcomes were measured by the Glasgow outcome score (GOS), modified ranking score (mRS) and the EuroQoL; healthcare costs were estimated per patient at discharge from hospital and at 12 months follow-up. In addition, Quality Adjusted Life Years (QALYs) were calculated from the EQ-5D utility scores. Cost–utility analysis was performed using the NHS and Social Care perspective.

A total of 49 patients were included; 35 were treated within 48 hours, ‘early’ (median (IQR) 8.25 [3.7–20.5]) and 14 were treated after 48 hours ‘delayed’ (median (IQR) 93.9 [66.7–100.1]). At discharge, 30 (86%) in the early treatment group had a good mRS outcome score (0–3) compared with 4 (29%) in the delayed group. According to GOS, 10 (29%) had a good recovery in the early treatment group, but only 1 (7%) in the delayed group. EQ-5D-3L utility value at discharge was significantly higher for early treatment (0.609 vs 0.221, p

This study suggests that early treatment may be associated with better health outcomes and reduced patient healthcare costs, with a potential for savings to the NHS with faster treatment.