Varicella zoster virus (VZV) is a human herpes virus that causes chickenpox (or varicella) and shingles. Chickenpox, which occurs with primary VZV infection, is highly contagious and is typically a mild illness in childhood. Shingles, which occurs with reactivation of latent VZV, is less common in childhood than adulthood but can still affect both immunocompromised and immunocompetent children following previous chickenpox infection or varicella vaccination.

The UK Health Security Agency (UKHSA) ‘guidelines on postexposure prophylaxis (PEP) for varicella/shingles’ were first published in April 2022 and updated in January 2023.1 They provide national recommendations for PEP in people at high risk of developing severe chickenpox following an exposure; this group consists primarily of vulnerable neonates and infants, immunosuppressed individuals and pregnant individuals (as well as the developing fetus). The guidelines focus on PEP rather than on the clinical management of chickenpox or shingles.

The UKHSA assumed responsibility for the health protection functions of Public Health England (PHE) from October 2021. The UKHSA guidelines thus represent an update of PHE’s 2019 guidance on the subject.

The National Institute for Health and Care Excellence (NICE) guidelines on the management of exposure to chickenpox were updated in February 2023. They recommend that primary care practitioners perform a general assessment, establish key information about the exposure and seek urgent or same-day specialist advice for vulnerable at-risk patients exposed to VZV.

The Royal College of Obstetrics and Gynaecology (RCOG) guidelines for chickenpox in pregnancy (Green-top Guideline No. 13) were last updated in January 2015 and reflect previous recommendations where varicella zoster immunoglobulin (VZIG) was offered as first-line PEP to exposed pregnant individuals.

Links to the full UKHSA guidelines, to the abovementioned NICE and RCOG guidelines and to relevant chapters in the Green Book (which provides UK health professionals with information on immunisation) are provided in …