Herpes Zoster and Immunogenicity and Safety of Zoster Vaccines in Transplant Patients: A Narrative Review of the Literature

Abstract

This narrative review focuses on the herpes zoster (HZ) and its prevention in transplant patients. Varicella zoster virus (VZV) is highly contagious and distributed worldwide in humans. Primary VZV infection usually causes varicella and then establishes a lifelong latency in dorsal root ganglia. Reactivation of VZV leads to HZ and related complications such as postherpetic neuralgia. Age and decreased immunity against VZV are important risk factors for developing HZ. Transplant patients are at increased risk for developing HZ and related complications due to their immunocompromised status and the need for lifetime immunosuppression. Diagnosis of HZ in transplant patients is often clinically difficult, and VZV-specific antibodies should be determined by serologic testing to document prior exposure to VZV during their pre-transplant evaluation process. Although antiviral agents are available, vaccination should be recommended for preventing HZ in transplant patients considering their complicated condition and weak organ function. Currently, there are two licensed HZ vaccines, of which one is a live-attenuated vaccine and the other is a HZ subunit vaccine. Both vaccines have shown promising safety and efficacy in transplants patients and especially the subunit vaccine could be administered post-transplant since this vaccine does not contain any live virus. Larger studies are needed about safety and immunogenicity of HZ vaccines in transplant populations, and extra efforts are needed to increase vaccine usage according to guidelines.

Shingles (Herpes Zoster) Mimicking Acute Abdomen

“…Varicella-zoster virus (VZV) was initially isolated in 1954 from the vesicular fluid of both chickenpox and zoster lesions in cell culture by Thomas Weller. In 1970 a live attenuated varicella vaccine was established in Japan [ 1 ].…”

“…Varicella-zoster virus (VZV) is a member of the α-herpesviruses subfamily and is a member of the Varicellovirus genus [ 1 ]. It can affect patients of any age, but primary VZV infection occurs during childhood leading to Varicella (chickenpox).…”

The beneficial effects of varicella zoster virus

“…Despite the rare reports of breakthrough VZV infections that may become disseminated and life-threatening particularly in immune compromised hosts, VZV vaccines including the live-attenuated ones are generally safe as shown by a 10 year global safety database as well as 2 systematic literature reviews, each of which included at least 31 million doses of VZV vaccines administered [151,[156][157][158][159]. VZV vaccines including the live attenuated ones have been shown to be safe in recipients of: SOT as well as HSCT, both autologous and allogeneic, in addition to patients with HMs and solid tumors [160][161][162][163][164][165][166][167][168]. Additionally, VZV vaccines have been shown to be effective and safe in: (1) patients with diabetes mellitus, autoimmune disorders and renal disease, (2) elderly individuals on corticosteroid maintenance therapy and those living in long-term care facilities, and (3) individuals with history of HZ infection [169][170][171][172][173].…”

Immunogenicity and Safety of a Live Herpes Zoster Vaccine in Hematopoietic Stem Cell Transplant Recipients

“…There are no clear guidelines regarding live vaccination after HSCT. With respect to HZ vaccines, limited data support vaccination after HSCT due to concerns about vaccine-induced VZV infection and lack of evidence regarding vaccine-induced immunogenicity [6][7][8]. Vaccination against HZ might be considered only when 24 months have elapsed since HSCT, and only in recipients showing no signs of graft-versushost disease (GvHD) or relapse, and in those not taking immunosuppressants [9][10][11].…”