Paeds · infectious-diseases
Varicella and herpes zoster
Also known as Chickenpox · Shingles · Varicella-zoster virus infection · Primary varicella · Herpes zoster reactivation · Human herpesvirus 3 infection
Fellowship topic on varicella (chickenpox) and herpes zoster (shingles) in children: the varicella-zoster virus and its neurotropic latency-and-reactivation biology; primary varicella with its crops of vesicles in all stages at once, and the dermatomal unilateral rash of zoster; the host-risk tiers that decide management from supportive care in the healthy child to intravenous aciclovir in the immunocompromised, neonate and pregnant patient; PCR and clinical diagnosis; the complications (pneumonia, encephalitis and cerebellitis, invasive group A streptococcal infection, congenital and neonatal varicella); the differential of vesicular rashes; isolation and exclusion rules; post-exposure prophylaxis with vaccine and varicella-zoster immune globulin; the two-dose live-attenuated varicella vaccine programme and the recombinant zoster vaccine; and ANZ, UK, US and Canada guidance.
On this page
Study tools
Your progress
Saved on this device.
Practise this topic
Target exams
Red flags
- An immunocompromised child, neonate, or pregnant adolescent with primary varicella — risk of disseminated, fatal disease; treat with intravenous aciclovir urgently and admit
- Varicella pneumonia — the commonest severe complication and a leading cause of varicella death, especially in adolescents, adults and the immunocompromised
- Central nervous system involvement — encephalitis, acute cerebellar ataxia, or meningoencephalitis; cerebellitis is the classic VZV CNS complication in children
- Invasive group A streptococcal infection complicating varicella — necrotising fasciitis or sepsis arising from a skin lesion; a leading cause of varicella-related death
- Congenital varicella syndrome after maternal primary infection in early pregnancy, and severe neonatal varicella from peripartum maternal infection — both preventable and both dangerous
Life stages
Care settings
Clinical exam formats
Board mappings
- General Paediatrics and Infectious Diseases: varicella and herpes zoster — clinical recognition, complications, treatment and prevention
- Immunisation: the two-dose live varicella vaccine schedule and post-exposure prophylaxis
- Renewed curriculum — Infectious diseases: varicella-zoster recognition, antiviral therapy, post-exposure prophylaxis and notification
- Community and population child health: the varicella vaccine programme, herd immunity and outbreak response
- General Paediatrics: varicella — diagnosis and management of the healthy child, the immunocompromised child and the neonate
- Public health: isolation, exclusion, notification and post-exposure prophylaxis
- Long Case / Structured discussion: the immunocompromised child with varicella, or the pregnant adolescent — risk stratification, antiviral therapy and prevention
- Communication station: explaining varicella, exclusion, post-exposure prophylaxis and vaccination to a family
- Level 2 / 3 — Infection: varicella as a vaccine-preventable infection; clinical features, complications, treatment and public-health responsibilities
- Public health and immunisation: the two-dose varicella programme, post-exposure prophylaxis and notification
- Foundation of Practice (FOP): varicella and zoster clinical features, complications and the vesicular-rash differential
- Applied Knowledge in Practice (AKP): antiviral therapy by risk tier, post-exposure prophylaxis and immunisation strategy
- History-taking and management: the child with a vesicular rash or the pregnant adolescent with a varicella contact
- Communication: explaining varicella, exclusion, post-exposure prophylaxis and vaccination to a family
- General Pediatrics Content Outline — varicella and herpes zoster: diagnosis, complications, treatment and prevention
- Infectious Diseases: varicella-zoster virus, PCR diagnosis, aciclovir therapy and post-exposure prophylaxis
- Bright Futures / immunisation: two-dose varicella vaccine schedule and post-exposure vaccination
- Patient Care: diagnosis and risk-stratified management of varicella and herpes zoster across age and immune status
- Systems-Based Practice and Population Health: isolation, notification, post-exposure prophylaxis and the immunisation programme
- Medical Knowledge: varicella-zoster latency and reactivation biology, complications and vaccine strategy
- Medical Expert: varicella and zoster diagnosis, complications and treatment
- Health Advocate and Collaborator: immunisation, post-exposure prophylaxis, notification and public-health coordination
- Communicator: explaining varicella, exclusion and prevention to families
One virus, two diseases
Primary varicella (chickenpox)
Herpes zoster (shingles)
"Crops, all stages, crusts to clear" — successive waves of vesicles mean you see papules, vesicles, pustules and crusts simultaneously, unlike the single-age crop of smallpox or the fixed progression of an enterovirus. The child is contagious until every lesion has crusted, and the lesions favour the trunk and face, sparing the palms and soles. Add the "dewdrop on a rose petal" vesicle description and the clinical diagnosis is made. [2] [1]
Overview & Definition
Picture a three-year-old brought in with a fever and an itchy rash that began on the trunk two days ago and now covers the face and limbs. The mother points out that some spots are red bumps, some are small blisters, and some are already scabbed over — and that is the single most useful bedside observation in paediatrics, because lesions of all stages at once is the signature of varicella. Recognising it instantly triggers the infection-control and public-health response that protects the vulnerable contacts behind this child. [2] [1]
Varicella, or chickenpox, is the primary systemic infection caused by the varicella-zoster virus, a highly contagious human neurotropic herpesvirus spread by respiratory droplets and direct contact with vesicle fluid. After the acute illness resolves, the virus establishes lifelong latency in the dorsal root and cranial-nerve ganglia. Decades later, when cell-mediated immunity wanes, the latent virus can reactivate along a single dermatome to produce herpes zoster, or shingles. The two diseases are therefore one virus observed at two points in a lifetime. [1] [5]
For most healthy children, varicella is a mild, self-limiting febrile illness. The clinician's job has two halves, and the second is what the fellowship examiner tests. The acute half is to confirm the diagnosis, gauge the host-risk tier, treat accordingly, and prevent spread. The preventive half is to deliver the immunisation programme, protect the non-immune high-risk contact after exposure, and understand the latency-and-reactivation biology that connects chickenpox today to shingles in decades to come. [7] [1]
References11ShowHide
- [1]WHO Varicella and herpes zoster vaccines: WHO position paper, June 2014--Recommendations. Vaccine, 2016.PMID 26723191
- [2]Marin M; Guris D; Chaves SS; Schmid S; Seward JF Prevention of varicella: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep, 2007.PMID 17585291
- [3]Vázquez M, LaRussa PS, Gershon AA, et al. The effectiveness of the varicella vaccine in clinical practice. N Engl J Med, 2001.PMID 11274621
- [4]Kuter BL; Brown AE; Hesley TM; Chalikonda I; et al Ten year follow-up of healthy children who received one or two injections of varicella vaccine. Pediatr Infect Dis J, 2004.PMID 14872179
- [5]Harpaz R; Ortega-Sanchez IR; Seward JF Prevention of herpes zoster: recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR Recomm Rep, 2008.PMID 18528318
- [6]Klassen TP; Belseck EM; Wiebe N; Hartling L Acyclovir for treating varicella in otherwise healthy children and adolescents. Cochrane Database Syst Rev, 2005.PMID 16235308
- [7]Marin M; Meissner HC; Seward JF Varicella prevention in the United States: a review of successes and challenges. Pediatrics, 2008.PMID 18762511
- [8]Chaves SS; Lopez AS; Watson TL; Civen R; et al Varicella in infants after implementation of the US varicella vaccination program. Pediatrics, 2011.PMID 22123875
- [9]Chaves SS; Gargiullo P; Zhang JX; Civen R; et al Varicella disease among vaccinated persons: clinical and epidemiological characteristics. J Infect Dis, 2008.PMID 18419385
- [10]Willer DO; Oostvogels L; de la Torre F; Collins M; et al Efficacy of the adjuvanted recombinant zoster vaccine (RZV) by sex, geographic region, and geographic ancestry/ethnicity: A post-hoc analysis of the ZOE-50 and ZOE-70 randomized trials. Vaccine, 2019.PMID 31537443
- [11]Enders G; Miller E; Cradock-Watson J; Bolley I; Ridehalgh M Consequences of varicella and herpes zoster in pregnancy: prospective study of 1739 cases. Lancet, 1994.PMID 7802767