Vaccine Induced Herpes Zoster in An Immunocompetent Child After 3 months of 1st Dose of Vaccination

Abstract

Varicella zoster virus (VZV) is an enveloped double stranded linear virus, which belongs to the herpesvirus’s family. It can cause two clinically different forms of diseases, primary infection known as chicken pox and latent infection know as herpes zoster (Shingles). Primary infection presents with diffuse vesicular rash accompanied by fever, malaise, and pharyngitis. However, latent infection results from reactivation of dormant virus in an immunocompromised patient and presents with painful localized skin rashes called as shingles. Currently, in the US, 2 doses of live attenuated varicella vaccine are available to prevent VZV infection. One of the major side effects of vaccination are the rashes. We report a unique case of vaccine induced VZV infection in a previously healthy child that presents with vesicular rashes 3 months after 1st dose of vaccination. A 16-month-old child with past medical history of premature birth at 32 weeks, presented to the pediatric outpatient clinic with complains of well-demarcated, erythematous, dry rash on both labia. Parents denied fever, cough, or any other signs and symptoms associated with rashes. patient activity level was normal and oral intake was usual. PCR testing was performed was found to be negative for Herpes Simplex Virus-1 (HSV-1) and Herpes Simplex Virus-2 (HSV-2) and positive for VZV. Due to patient recent vaccination status, further classification of infection was needed to determine if the source of infection was wild type chicken pox or vaccine induced. A swab of one of the vesicular lesions was sent to the Ohio Department of Health, for vaccine vs wild-type strain PCR testing. The results were positive for Vaccine induced VZV infection. The patient was started on acyclovir therapy. On follow-up, the patient condition improved clinically. In pediatric populations, it is important to do extensive evaluation of rashes post vaccination as it can be occurred due to wild type, break through or it can be vaccine induced virus. Proper evaluation can significantly impact the management patients as they are maybe infectious and need to be isolated in wild type and breakthrough infection versus non-infectious in case of vaccine induced. After detailed clinical history and physical examination, it is important to investigate further through PCR testing to differentiate one category from another!