21st February 2024

Treatment

Varicella is a highly infectious disease notifiable in Scotland and Northern Ireland. The condition usually begins with fever and malaise that lasts approximately 1-2 days before the onset of vesicles along the face, trunk, abdomen and limbs in order of progression. This will last for approximately 3-4 days before scabbing over. The virus may actively spread through the droplets or via contact with vesicular fluid until the vesicles dry up. Shingles can also result in varicella spread, as the reactivation of the varicella virus causes it. Chickenpox typically affects children, and the condition often runs a mild course, with shingles more prevalent in the elderly and immunocompromised population. 

Adults can also develop chickenpox if they have not been affected by this during their childhood. Adults and pregnant women are at higher risk when they have developed varicella infection due to the risk of fulminating varicella pneumonia and foetal varicella infection, respectively. Foetal varicella infection can result in foetal varicella syndrome, characterised by limb hypoplasia, microcephaly, cataracts, growth restriction, chorioretinal damage, and sudden foetal demise. 

The disease is usually self-limiting for most patients, and most patients will require supportive care and aciclovir. Varicella immunoglobulins (VZIG) are available to help reduce the likelihood of a high-risk patient developing severe varicella infection. The patient needs to fulfil the following criteria to be eligible for VZIG: 

• Significant exposure towards varicella
  • Disseminated zoster
  • Immunocompetent individuals with exposed lesions
  • Immunosuppressed individuals with localised lesions on any part of the body. 
• Timing of exposure to rash onset
  • Exposure to the patient 48 hours prior to the rash onset until the crusting of lesions for disseminated zoster OR from the day of onset of rash until crusting of lesions for localised zoster. 
• Closeness of contact – Does not apply to neonatal/maternal exposure
  • Contact in the same room (house/classroom/ward) for > 15  minutes.
  • Face-to-face conversation

The patient’s varicella antibody status also should be known, and the advice given will depend on the patient population. Below is the summary of the advice given by the Green Book:

*Immunocompromised is defined as patients with severe primary immunodeficiency; ongoing immunosuppressive treatment with chemotherapy, radiotherapy, biologics, corticosteroids and non-steroids immunosuppressive agents; HIV and stem cell transplant recipients. 

Varicella immunisation should not be given during the acute event, and the vaccine is contraindicated in both situations. Varicella vaccination can be considered in pregnant women once they have given birth.