Congenital varicella syndrome (CVS) is a very rare disorder that presents from birth, as a result of the mother being infected with chickenpox (maternal varicella zoster) early during pregnancy (usually in the first 20 weeks).^1,2 Infants with CVS often have low birth weight and may be born with abnormalities of the skin, eyes, brain, arms, legs, hands and feet. The symptoms of this disorder can be severe, but varies between individuals.^1,2

Women who are planning pregnancy are recommended to be vaccinated against the varicella zoster virus (VZV), or to do a blood test to check if they have immunity to VZV.^3,4 Vaccination during pregnancy is not advised.⁴ Pregnant women who have not had chickenpox, or have been tested to not have immunity to chickenpox (seronegative), are advised to avoid any contact with those who have chickenpox or shingles, throughout their pregnancy. If they have come into such contact, they should seek medical advice from doctors immediately.⁵ In addition to the risk of CVS during early pregnancy, a maternal infection during late pregnancy (perinatal varicella infection) can also pose risks to the child – newborns can develop chickenpox (neonatal varicella infection), which in some cases can be severe and fatal.⁶

Synonyms: Antenatal varicella virus infection; mother-to-child transmission of varicella syndrome; fetal varicella syndrome.¹

Universal rare disease classifications provide a common language for recording, reporting and monitoring diseases. Please visit the Rare Disease Classifications page for more information about these internationally recognised classifications.

ORPHA:291 Congenital varicella syndrome

ICD-11: KA62.2 Congenital Varicella Zoster virus infection

The presentation and severity of CVS can vary between individuals.¹ Signs and symptoms of CVS may include:^1-3

• low birth weight
• scarring of the skin
• limb defects, such as underdeveloped arms, legs and muscles
• eye defects
• small head (microcephaly) and underdeveloped brain
• intellectual disabilites
• seizures
• issues with bladder, kidney, stomach and intestine

There may be complications including issues with the bladder, kidney and intestine as well as gastroesophageal reflux and respiratory issues, which can be severe and life-threatening.² Babies can also develop painful infant shingles (herpes zoster) within the first few years of life.

Please speak to your medical team to learn more about the symptoms and complications of CVS.

Rare diseases are often serious and progressive, exhibiting a high degree of symptom complexity, leading to significant disability. Majority of the estimated two million Australians living with a rare disease meet the Australian Government’s definition for disability (in accordance to the Australian Public Service Commission and Australian Bureau of Statistics), and many experience severe and permanent disability impacts. If you or someone you care for is experiencing disability-related impacts from a rare condition, please speak with a health or disability professional for advice. Information about relevant disability support can be found at the RARE Portal’s Disability Support Information page.

Whilst it is rare, a chicken pox infection during early pregnancy (maternal varicella zoster) can result in a baby being born with CVS.^1,3

Diagnosis of a varicella zoster virus (VZV) infection can be made through testing for antibodies against VZV in the blood or viral detection in the blood, fluid or tissue samples.⁶ More information about these tests can be found at Pathology Tests Explained: Varicella zoster virus.

CVS is usually diagnosed through confirmation of a maternal VZV infection early in pregnancy and presentation of clinical features of CVS in the newborn.² In some cases, prenatal ultrasounds may be able to detect signs of CVS before the child is born.

Please speak to your medical team to learn more about the available diagnostic pathways for CVS.

There is currently no curative treatment for CVS. Treatment may be limited due to the severity of this condition.

Please speak to your medical team to learn more about the possible treatment or management options for your condition. Treatment will depend on an individual’s specific condition and symptoms. It is also important to stay connected to your medical team so that you can be made aware of any upcoming clinical trial opportunities.

Clinical care for rare diseases often involves a multidisciplinary team of medical, care and support professionals. Please note that the information provided here is as a guide and that RVA does not necessarily monitor or endorse specific clinics or health experts.

Healthcare professionals involved in the treatment of CVS may include general practitioners (GP), paediatricians, infectious disease specialists, ophthalmologists (eye specialists), neurologists, surgeons and physical therapists.² The need for different healthcare professionals may change over a person’s lifetime and may extend beyond those listed here.

There are guidelines for management of varicella infection (chickenpox) in pregnancy; however some of them are from other countries and may not be relevant or applicable to the Australian context; and may not be up to date:

• South Australia (SA) Health: Varicella Zoster (chicken pox) in Pregnancy Clinical Guidelines; please note that this was last updated in 2015
• Society of Obstetricians and Gynaecologists of Canada: Management of Varicella Infection (Chickenpox) in Pregnancy; please note that this was published in 2012
• Royal College of Obstetrics and Gynecology UK: Chickenpox in Pregnancy; please note that this was published in 2015

Individuals living with rare diseases may have complex medical issues and disabilities, which are not always visible. It is often useful to refer to their medical history as well as personal information such as a medical card, doctor’s letter, or if available, a rare disease passport, for relevant information.

There are specific considerations around participating in rare disease research, including clinical trials. It is important to be mindful of issues such as data privacy, research ethics, consent and differences in research regulations between Australia and other countries.

If you are interested in finding clinical trials for your condition, please visit the following websites; however, there may not be any clinical trials available:

• Australian Clinical Trials
• ClinicalTrials.gov

It is best to discuss your interest in any clinical trials with your medical team to determine suitability and eligibility.

Please note that RVA does not necessarily monitor or endorse each group/organisation’s operational governance and activities.

We are not aware of any rare disease organisations for CVS in Australia or internationally. If you know of any rare disease organisation supporting people living with CVS, please let us know via the Contribute page. If you are interested in starting an Australian organisation, please see Engaged, Ethical and Effective: A Guide for Rare Disease Organisation Leaders in Australia.

Please note that RVA does not monitor or endorse each group/organisation’s operational governance and activities. When engaging with a group, please consider the information on the RARE Portal’s Finding Helpful Peer and Community Supports page.

CVS varies between individuals, and each person’s experience is unique.

If you would like to share your personal story with RVA, please visit the Rare Voices Australia: Share Your Story page. RVA will consider your story for publishing on our website and inclusion on the RARE Portal.

For information on available government and social services that provide support for individuals with a rare disease, please visit the National and State Services pages.

People living with a rare disease, including families and carers, often face unique challenges such as diagnostic delays, misdiagnoses, limited treatment options, and limited access to rare disease specialists and support. These challenges may impact people’s emotional wellbeing and quality of life. Many people find it helpful to seek mental health and wellbeing support to cope with ongoing stress and uncertainty. Connecting with people who have shared experiences through a support group may also be helpful. Information about relevant mental health and wellbeing support can be found at:

• Mental Health and Wellbeing Support for Australians Living with a Rare Disease
• The National and State Services pages underneath the ‘Mental Health’ sections listed

Further information about CVS can be found at:

• healthdirect: Chickenpox (varicella) (including a section on chickenpox and pregnancy)
• National Organization for Rare Disorders (NORD): Congenital Varicella Syndrome
• Genetic and Rare Diseases (GARD) Information Center – Congenital Varicella Syndrome

Below is some information about varicella:

• varicella is a notifiable disease in most states and territories in Australia.³ State and territory public health authorities should be informed or consulted about cases of varicella.
• information about varicella (chickenpox) vaccination, including other contraindications, can be found at The Australian Immunisation Handbook: Varicella (chickenpox) vaccine information.

• Orphanet: Congenital varicella syndrome
• Human Phenotype Ontology (HPO): Congenital varicella syndrome

This page has been developed by Rare Voices Australia (RVA)’s RARE Portal team.

If you are aware of any additional information that may benefit stakeholders with an interest in this page, or if you notice any broken links or inaccurate information, please let us know via the Contribute page.