Boosting immune response with a candidate varicella-zoster virus glycoprotein subunit vaccine

Rapid, sensitive, and specific lateral-flow immunochromatographic point-of-care device for detection of varicella-zoster virus immunoglobulin G antibodies in fingerstick blood

Varicella zoster virus (VZV) causes childhood chickenpox, becomes latent in sensory ganglia and reactivates years later to cause shingles (Zoster) and postherpetic neuralgia in the elderly and immunosuppressed individuals. Serologic IgG tests can be used to determine if a person has antibodies to VZV from past varicella infection or had received varicella or zoster (shingles) vaccination. Commercial enzyme-linked immunosorbent assays (ELISAs) are currently used for the detection of VZV IgG antibodies in patient serum samples. However, ELISA tests require collection and processing of blood samples in a CLIA laboratory to separate serum or plasma for further testing. In this paper, we describe the development and testing of an antibody based Lateral Flow Immunochromatographic assay (LFA) device for the detection of VZV IgG in fingerstick whole blood. Analytical and clinical analyses were performed to compare the performance characteristics of the Viro VZV IgG LFA (VZV LFA) and the Diamedix VZV IgG ELISA. Analytical studies demonstrated the higher sensitivity of the VZV LFA compared to the ELISA by testing dilutions of the WHO VZV IgG serum International Standard. Clinical performance characteristics of the VZV LFA fingerstick whole blood assay were assessed at three point of care (POC) facilities by untrained users testing samples from 300 prospectively enrolled study subjects. VZV LFA results were compared with results obtained by testing serum samples obtained from the same study participants by the Diamedix VZV IgG ELISA. Two specimens with invalid results by the LFA assay were not included in the LFA performance calculations and nine equivocal ELISA results were included as positive for IgG results. The results from all three POC clinical sites demonstrated the higher sensitivity/positive percent agreement (PPA) (99.26%, 95% CI: 97.34-99.80) of the VZV LFA compared to the Diamedix VZV IgG ELISA (94.08%, 95% CI: 90.72-96.27). The specificity/negative percent agreement (NPA) of the VZV LFA compared to the ELISA test was calculated initially to be 39.29% (95% CI: 23.57-57.59) with 19 discordant test results out of 298 test results between the two assays (17 LFA positive/ELISA negative and two LFA negative/ELISA positive). The PPA and true NPA of the VZV LFA were determined by testing all 298 samples, including the discordant (19) and all concordant negative and positive (279) study subject serum samples, before and after blocking VZV gE antibody sites in the samples by spiking with VZV LFA gE capture antigen. The NPA improved to 100% (95% CI: 74.12-100) after the procedure when compared to the ELISA test results. The comparator ELISA PPA based on the spiking/blocking study remained as 94.08%, (95% CI: 90.72-96.27), comparable to test results from untreated samples. The VZV LFA has been demonstrated to be simple and sufficiently robust for use in CLIA-waived POC facilities by untrained healthcare professionals and to detect VZV IgG in 20 min from fingerstick whole blood. The VZV LFA therefore provides a fast, reliable, and highly sensitive method of determining prior VZV viral infection or varicella and zoster vaccination status.

Preclinical advances and the immunophysiology of a new therapeutic chagas disease vaccine

INTRODUCTION

Chronic infection with the protozoal parasite Trypanosoma cruzi leads to a progressive cardiac disease, known as chronic Chagasic cardiomyopathy (CCC). A new therapeutic Chagas disease vaccine is in development to augment existing antiparasitic chemotherapy drugs.

AREAS COVERED

We report on our current understanding of the underlying immunologic and physiologic mechanisms that lead to CCC, including parasite immune escape mechanisms that allow persistence and the subsequent inflammatory and fibrotic processes that lead to clinical disease. We report on vaccine design and the observed immunotherapeutic effects including induction of a balanced T_H1/T_H2/T_H17 immune response that leads to reduced parasite burdens and tissue pathology. Further, we report vaccine-linked chemotherapy, a dose sparing strategy to further reduce parasite burdens and tissue pathology.

EXPERT OPINION

Our vaccine-linked chemotherapeutic approach is a multimodal treatment strategy, addressing both the parasite persistence and the underlying deleterious host inflammatory and fibrotic responses that lead to cardiac dysfunction. In targeting treatment towards patients with chronic indeterminate or early determinate Chagas disease, this vaccine-linked chemotherapeutic approach will be highly economical and will reduce the global disease burden and deaths due to CCC.

Vaccines for older adults

The proportion of the global population aged 65 and older is rapidly increasing. Infections in this age group, most recently with SARS-CoV-2, cause substantial morbidity and mortality. Major improvements have been made in vaccines for older people, either through the addition of novel adjuvants-as in the new recombinant zoster vaccine and an adjuvanted influenza vaccine-or by increasing antigen concentration, as in influenza vaccines. In this article we review improvements in immunization for the three most important vaccine preventable diseases of aging. The recombinant zoster vaccine has an efficacy of 90% that is minimally affected by the age of the person being vaccinated and persists for more than four years. Increasing antigen dose or inclusion of adjuvant has improved the immunogenicity of influenza vaccines in older adults, although the relative effectiveness of the enhanced influenza vaccines and the durability of the immune response are the focus of ongoing clinical trials. Conjugate and polysaccharide pneumococcal vaccines have similar efficacy against invasive pneumococcal disease and pneumococcal pneumonia caused by vaccine serotypes in older adults. Their relative value varies by setting, depending on the prevalence of vaccine serotypes, largely related to conjugate vaccine coverage in children. Improved efficacy will increase public confidence and uptake of these vaccines. Co-administration of these vaccines is feasible and important for maximal uptake in older people. Development of new vaccine platforms has accelerated following the arrival of SARS-CoV-2, and will likely result in new vaccines against other pathogens in the future.

Herpes Zoster Vaccines

Background

Immunization for herpes zoster (HZ) aims to reverse the decline in cell-mediated immunity to varicella zoster virus that occurs with advancing age or immunocompromise. There are 2 vaccines available, one live attenuated (Zoster vaccine, live attenuated [ZVL]) and, recently, a recombinant subunit vaccine (HZ/su).

Methods

The literature relevant to the two HZ vaccines was reviewed.

Results

ZVL has overall efficacies of 51% and 65% against HZ and postherpetic neuralgia, respectively, with a prominent decline in efficacy with advancing age of the vaccinee. This compares to approximately 90% efficacy against HZ for HZ/su that is minimally affected with advancing age. The efficacy of ZVL against HZ declines over 4 and 8 years, compared with minimal decline so far over 4 years with HZ/su, and immunogenicity that is maintained for 9 years. Local and systemic reactogenicity to HZ/su is much greater than to ZVL.

Conclusions

HZ/su establishes an important principle-that a single recombinant viral protein with an effective adjuvant combination can stimulate immunogenicity superior to that of a live attenuated vaccine, and that this can diminish immunosenescence. This provides hope for improvement of other vaccines for aging patients. However, key questions remain unanswered, including the durability of the efficacy of HZ/su, its efficacy as a booster for previous recipients of ZVL, and its efficacy in immunocompromised patients.

Immune Responses to a Recombinant Glycoprotein E Herpes Zoster Vaccine in Adults Aged 50 Years or Older

Background

The herpes zoster subunit vaccine (HZ/su), consisting of varicella-zoster virus glycoprotein E (gE) and AS01_B Adjuvant System, was highly efficacious in preventing herpes zoster in the ZOE-50 and ZOE-70 trials. We present immunogenicity results from those trials.

Methods

Participants (ZOE-50: ≥50; ZOE-70: ≥70 years of age) received 2 doses of HZ/su or placebo, 2 months apart. Serum anti-gE antibodies and CD4 T cells expressing ≥2 of 4 activation markers assessed (CD4²⁺) after stimulation with gE-peptides were measured in subcohorts for humoral (n = 3293) and cell-mediated (n = 466) immunogenicity.

Results

After vaccination, 97.8% of HZ/su and 2.0% of placebo recipients showed a humoral response. Geometric mean anti-gE antibody concentrations increased 39.1-fold and 8.3-fold over baseline in HZ/su recipients at 1 and 36 months post-dose 2, respectively. A gE-specific CD4²⁺ T-cell response was shown in 93.3% of HZ/su and 0% of placebo recipients. Median CD4²⁺ T-cell frequencies increased 24.6-fold (1 month) and 7.9-fold (36 months) over baseline in HZ/su recipients and remained ≥5.6-fold above baseline in all age groups at 36 months. The proportion of CD4 T cells expressing all 4 activation markers increased over time in all age groups.

Conclusions

Most HZ/su recipients developed robust immune responses persisting for 3 years following vaccination.

Clinical Trials Registration

NCT01165177; NCT01165229.

Development of adjuvanted recombinant zoster vaccine and its implications for shingles prevention

INTRODUCTION

GSK has developed a two-dose adjuvanted recombinant zoster vaccine (Shingrix, RZV) to protect people aged ≥50 years (50+) against herpes zoster (HZ) and its complications. RZV showed >90% efficacy against HZ, sustained over 4 years of follow-up, in all studied age groups.

AREAS COVERED

This article reviews the scientific rationale underlying the design of RZV; the clinical evidence demonstrating immunogenicity, safety, and efficacy in persons 50+; and the public health implications and cost-effectiveness.

EXPERT COMMENTARY

A decline in varicella zoster virus (VZV) immunity is associated with increased risk of HZ in adults 50+ and immunocompromised individuals. RZV was designed to restore levels of anti-VZV cellular and humoral immunity to prevent VZV reactivation. RZV includes the recombinant gE glycoprotein antigen, and Adjuvant System AS01_B which promotes cellular and antibody responses. In two Phase III studies in subjects aged 50+ and 70+ years, RZV efficacy against HZ compared to placebo was >90% and ≥89% against post-herpetic neuralgia (PHN). RZV is expected to dramatically impact HZ morbidity including its complications, and associated health-care costs. In the US population aged 50+ years, vaccination with RZV can be cost-effective compared to no vaccination and cost-saving compared to the currently available live-attenuated HZ vaccine (Zostavax, Merck).

Immunogenicity and Safety of the HZ/su Adjuvanted Herpes Zoster Subunit Vaccine in Adults Previously Vaccinated With a Live Attenuated Herpes Zoster Vaccine

Background

Protection against herpes zoster (HZ) induced by the live attenuated zoster vaccine Zostavax (ZVL) wanes within 3–7 years. Revaccination may renew protection. We assessed whether (re)vaccination with the adjuvanted HZ subunit vaccine candidate (HZ/su) induced comparable immune responses in previous ZVL recipients and ZVL-naive individuals (HZ-NonVac).

Methods

In an open-label, multicenter study, adults ≥65 years of age, vaccinated with ZVL ≥5 years previously (HZ-PreVac), were matched to ZVL-naive adults (HZ-NonVac). Participants received 2 doses of HZ/su 2 months apart. The primary objective of noninferiority of the humoral immune response 1 month post–dose 2 was considered demonstrated if the upper limit of the 95% confidence interval (CI) of the adjusted anti–glycoprotein E geometric mean concentration (GMC) ratio of HZ-NonVac over HZ-PreVac was <1.5. HZ/su cellular immunogenicity, reactogenicity, and safety were also assessed.

Results

In 430 participants, humoral immune response to HZ/su was noninferior in HZ-PreVac compared with HZ-NonVac (adjusted GMC ratio, 1.04 [95% CI, .92–1.17]). Cellular immunogenicity, reactogenicity, and safety appeared to be comparable between groups. HZ/su was well-tolerated, with no safety concerns raised within 1 month post–dose 2.

Conclusions

HZ/su induces a strong immune response irrespective of prior vaccination with ZVL, and may be an attractive option to revaccinate prior ZVL recipients.

Clinical Trials Registration

NCT02581410.

Vaccine profile of herpes zoster (HZ/su) subunit vaccine

INTRODUCTION

Herpes zoster (HZ) causes an often severe and painful rash in older people and may be complicated by prolonged pain (postherpetic neuralgia; PHN) and by dissemination in immune-compromised patients. HZ results from reactivation of latent varicella-zoster virus (VZV) infection, often associated with age-related or other causes of decreased T cell immunity. A live attenuated vaccine boosts this immunity and provides partial protection against HZ, but this decreases with age and declines over 8 years. Areas covered: A new HZ subunit (HZ/su) vaccine combines a key surface VZV glycoprotein (E) with a T cell-boosting adjuvant system (AS01_B) and is administered by two intramuscular injections two months apart. Expert commentary: HZ/su showed excellent efficacy of ~90% in immunocompetent adults ≥50 and ≥70 years of age, respectively, in the ZOE-50 and ZOE-70 phase III controlled trials. Efficacy was unaffected by advancing age and persisted for >3 years. Approximately 9.5% of subjects had severe, but transient (1-2 days) injection site pain, swelling or redness. Compliance with both vaccine doses was high (95%). The vaccine will have a major impact on HZ management. Phase I-II trials showed safety and immunogenicity in severely immunocompromised patients. Phase III trial results are expected soon.

The herpes zoster subunit vaccine

INTRODUCTION

Herpes zoster (HZ) causes severe pain and rash in older people and may be complicated by prolonged pain (postherpetic neuralgia; PHN).

AREAS COVERED

HZ results from reactivation of latent varicella-zoster virus (VZV) infection, often associated with age related or other causes of decreased T cell immunity. A concentrated live attenuated vaccine boosts this immunity and provides partial protection against HZ, but this decreases with age and declines over 5-8 years. The new HZ subunit (HZ/su or Shingrix) vaccine combines a key surface VZV glycoprotein (E) with T cell boosting adjuvant (AS01B). It is highly efficacious in protection (97%) against HZ in immunocompetent subjects, with no decline in advancing age and protection maintained for >3 years. Phase I-II trials showed safety and similar immunogenicity in severely immunocompromised patients. Local injection site pain and swelling can be severe in a minority (9.5%) but is transient (2 days).

EXPERT OPINION

The HZ/su vaccine appears very promising in immunocompetent patients in the ZoE-50 controlled trial. The unblinding of the current ZoE-50 trial and publication of results from the accompanying ZoE-70 trial will reveal more about its mechanism of action and its efficacy against PHN, particularly in subjects >70 years. Phase III trial results in immunocompromised patients are eagerly awaited.

Adjuvanted herpes zoster subunit vaccine

This review highlights the characteristics of a candidate herpes zoster (HZ) vaccine (HZ/su, GlaxoSmithKline Vaccines) that consists of 50 μg recombinant glycoprotein E (gE) of varicella zoster virus adjuvanted with AS01B. It is well tolerated and shows a clinically acceptable tolerability profile. It strongly enhances pre-existing gE-specific CD4+ T-cell and anti-gE antibody responses in older adults and immunocompromised persons. Administration of two doses 2 months apart reduces the risk of HZ by 97.2% in adults ≥50 years. This effect does not diminish with increasing age. Long-term persistence of its efficacy still needs to be determined. This candidate HZ vaccine may become an alternative for the high-dose live-attenuated varicella zoster virus vaccine for the prevention of HZ in older persons and in immunocompromised patients in whom the use of live-attenuated vaccines is contraindicated.

Long-term immunogenicity and safety of an investigational herpes zoster subunit vaccine in older adults

BACKGROUND

An investigational subunit vaccine containing the varicella-zoster virus (VZV) glycoprotein E (gE) and the AS01B adjuvant system is being evaluated for the prevention of herpes zoster (HZ) in older adults. A phase II trial evaluating different formulations of this vaccine (containing 25μg, 50μg, or 100μg gE) was conducted in adults ≥60 years of age and showed that all formulations elicited robust cellular and humoral immune responses for up to 3 years after vaccination. In this follow-up study in subjects who received two doses of the 50μg gE/AS01B formulation (HZ/su), we assessed the persistence of the immune responses for up to 6 years after vaccination.

METHODS

This phase II, open-label, multicenter, single-group trial conducted in the Czech Republic, Germany, Sweden, and the Netherlands followed 129 subjects who had received two doses (2 months apart) of HZ/su during the initial trial. Vaccine-induced immune responses (frequencies of gE-specific CD4(+) T cells expressing ≥2 activation markers and serum anti-gE antibody concentrations) were evaluated at 48, 60, and 72 months after the first HZ/su dose.

RESULTS

Six years after vaccination with HZ/su, gE-specific cell-mediated immune responses and anti-gE antibody concentrations had decreased by 20-25% from month 36, but remained higher than the prevaccination values. At month 72, the gE-specific cell-mediated immune response was 3.8 times higher than the prevaccination value (477.3 vs. 119.4 activated gE-specific CD4(+) T cells per 10(6) cells), and the anti-gE antibody concentration was 7.3 times higher than the prevaccination value (8159.0 vs. 1121.3mIU/mL). No vaccine-related serious adverse events were reported between months 36 and 72.

CONCLUSIONS

gE-specific cellular and humoral immune responses persisted for 6 years after two-dose vaccination with HZ/su in healthy older adults. No safety concerns were identified.

Efficacy of an adjuvanted herpes zoster subunit vaccine in older adults

BACKGROUND

In previous phase 1-2 clinical trials involving older adults, a subunit vaccine containing varicella-zoster virus glycoprotein E and the AS01B adjuvant system (called HZ/su) had a clinically acceptable safety profile and elicited a robust immune response.

METHODS

We conducted a randomized, placebo-controlled, phase 3 study in 18 countries to evaluate the efficacy and safety of HZ/su in older adults (≥50 years of age), stratified according to age group (50 to 59, 60 to 69, and ≥70 years). Participants received two intramuscular doses of the vaccine or placebo 2 months apart. The primary objective was to assess the efficacy of the vaccine, as compared with placebo, in reducing the risk of herpes zoster in older adults.

RESULTS

A total of 15,411 participants who could be evaluated received either the vaccine (7698 participants) or placebo (7713 participants). During a mean follow-up of 3.2 years, herpes zoster was confirmed in 6 participants in the vaccine group and in 210 participants in the placebo group (incidence rate, 0.3 vs. 9.1 per 1000 person-years) in the modified vaccinated cohort. Overall vaccine efficacy against herpes zoster was 97.2% (95% confidence interval [CI], 93.7 to 99.0; P<0.001). Vaccine efficacy was between 96.6% and 97.9% for all age groups. Solicited reports of injection-site and systemic reactions within 7 days after vaccination were more frequent in the vaccine group. There were solicited or unsolicited reports of grade 3 symptoms in 17.0% of vaccine recipients and 3.2% of placebo recipients. The proportions of participants who had serious adverse events or potential immune-mediated diseases or who died were similar in the two groups.

CONCLUSIONS

The HZ/su vaccine significantly reduced the risk of herpes zoster in adults who were 50 years of age or older. Vaccine efficacy in adults who were 70 years of age or older was similar to that in the other two age groups. (Funded by GlaxoSmithKline Biologicals; ZOE-50 ClinicalTrials.gov number, NCT01165177.).

Safety and immunogenicity of an adjuvanted herpes zoster subunit candidate vaccine in HIV-infected adults: a phase 1/2a randomized, placebo-controlled study

BACKGROUND

Human immunodeficiency virus (HIV)-infected individuals are at increased risk of herpes zoster (HZ), even in the antiretroviral therapy (ART) era. Because concerns exist about the use of live-attenuated vaccines in immunocompromised individuals, a subunit vaccine may be an appropriate alternative.

METHODS

This phase 1/2, randomized, placebo-controlled study evaluated the immunogenicity and safety of an investigational HZ subunit vaccine (HZ/su). Three cohorts of HIV-infected adults aged ≥18 years were enrolled: 94 ART recipients with a CD4(+) T-cell count of ≥200 cells/mm(3), 14 ART recipients with a CD4(+) T-cell count of 50-199 cells/mm(3), and 15 ART-naive adults with a CD4(+) T-cell count of ≥500 cells/mm(3). Subjects received 3 doses of HZ/su (50 µg varicella-zoster virus glycoprotein E [gE] combined with AS01B adjuvant) or 3 doses of saline at months 0, 2, and 6.

RESULTS

One month after dose 3, serum anti-gE antibody concentrations and frequencies of gE-specific CD4(+) T cells were higher following HZ/su vaccination than after receipt of saline (P < .0001). Median cell-mediated immune responses peaked after dose 2. Humoral and cell-mediated immune responses persisted until the end of the study (month 18). No vaccination-related serious adverse events were reported. No sustained impact on HIV load or CD4(+) T-cell count was noted following vaccinations.

CONCLUSIONS

HZ/su was immunogenic and had a clinically acceptable safety profile in HIV-infected adults.

CLINICAL TRIALS REGISTRATION

NCT01165203.

Cell-mediated immune responses to a varicella-zoster virus glycoprotein E vaccine using both a TLR agonist and QS21 in mice

Lack of adequate cell-mediated immunity (CMI) to varicella-zoster virus (VZV) has been associated with higher risks of developing herpes zoster (HZ) and associated post-herpetic neuralgia (PHN), and is of particular concern for older and immunocompromised individuals. Thus, the development of an effective HZ vaccine with a clinically acceptable safety profile that is capable of addressing decreased immunity would be highly desirable. In this study we compared the immunogenicity of different vaccine formulations containing VZV glycoprotein E (gE), an important target for CMI and antibody responses, in a VZV-primed mouse model. The formulations included recombinant gE, either unadjuvanted, or combined with aluminium salt or an Adjuvant System (AS01 or AS02), and CMI was used as the primary immunological endpoint. All adjuvanted vaccines induced gE- and/or VZV-specific CD4(+) T cell and antibody responses. A formulation of gE with an Adjuvant System containing the immunostimulants QS21 and 3-O-desacyl-4'-monophosphoryl lipid A (MPL) was shown to be more immunogenic than gE with aluminium salt or unadjuvanted gE (gE/saline). Both immunostimulants were shown to act synergistically in enhancing CMI responses. Formulations with AS01 elicited high frequencies of CD4(+) T cells producing IFN-γ and IL-2. These responses were dose-dependent with respect to both antigen and adjuvant. The gE/AS01(B) candidate vaccine induced higher frequencies of CD4(+) T cells producing IL-2 and/or IFN-γ than all other gE/AS01 formulations, supporting its use for clinical evaluations.

Effect of monophosphoryl lipid A (MPL) on T-helper cells when administered as an adjuvant with pneumocococcal-CRM197 conjugate vaccine in healthy toddlers

As new vaccines are developed, novel adjuvants may play an important role in eliciting an effective immune response. We evaluated the safety and adjuvant properties of monophosphoryl lipid A (MPL in 129 healthy toddlers immunized with two doses of nine-valent pneumococcal-CRM(197) protein conjugate vaccine (PCV9) combined with 10, 25, or 50 micro g of MPL with or without alum (AlPO(4)). Vaccine-specific humoral and cell-mediated responses were examined following the second dose of study vaccine. All doses of MPL were well-tolerated and a dose-dependent effect of MPL on specific cellular responses was observed. The 10 micro g MPL dose significantly enhanced CRM(197)-specific T-cell proliferation (P=0.02) and interferon-gamma (INF-gamma) production (P=0.009) compared to responses of controls who received PCV9 with AlPO(4). In contrast, CRM(197)-specific T-cell proliferation and interferon-gamma production of the 50 micro g MPL/AlPO(4) group were decreased when compared to controls although these differences did not reach statistical significance. IL-5 and IL-13 responses after immunization showed a similar pattern with increased production in the 10 micro g MPL group and decreased production in the 50 micro g MPL/AlPO(4) group compared to controls. There were no differences in serum IgG antibody concentrations to the nine vaccine pneumococcal capsular polysaccharides and carrier protein between the MPL-containing and control vaccine groups. These findings demonstrate a dose-dependent effect of MPL on T-helper cell type 1 (TH-1) responses to the carrier protein and also suggest an effect on T-helper cell type 2 (TH-2) responses.

Nucleotide sequence analysis of varicella-zoster virus glycoprotein E epitope coding regions

Varicella-zoster virus (VZV) glycoprotein E [gE] contains 623 amino acid residues. Fifty percent of the gE gene, codons 39 to 344 that encompasses two epitope coding regions e1 and c1, was sequenced and analyzed for variation among the 30 VZV isolates. A total of eleven isolates showed variance when compared with Dumas VZV strain sequence through base substitutions, with two isolates showing an amino acid change of tryptophan to arginine outside the coding regions of the epitopes e1 and c1 that are recognized by monoclonal antibodies 4F9 and c1, respectively. The results suggest that these epitopes were stable in the various VZV isolates. Thus, VZV glycoproteins with conserved epitopes are suitable candidates for both primary and booster vaccines.

Zoster in patients infected with HIV: a review

Varicella-zoster virus (VZV), a member of the human herpesvirus family, causes childhood chickenpox (varicella), becomes latent in sensory ganglia, and reactivates years later in immunocompromised and elderly persons to produce shingles (herpes zoster). Early in the AIDS epidemic, zoster was noted in adults and children infected with HIV. Severe and debilitating zoster-associated dermatological, ophthalmic, and neurological complications may occur in patients infected with HIV. Antiviral therapy can modify the duration of zoster and alleviate its attendant complications. Varicella vaccine may boost the immunity and prevent virus reactivation. VZV immune globulin (VZIG) prevents or modifies clinical illness in persons who have been exposed to varicella or zoster.

Vaccines for transplant recipients

Immune dysregulation and immunosuppression regimens impact on the ability of transplant recipients to respond to immunizations. The distinct challenges of immunizations to benefit stem cell transplant recipients and solid organ transplant recipients are discussed separately. Recommended vaccines for stem cell transplant recipients and solid organ transplant candidates are suggested. New approaches to consider to enhance immune responses of transplant recipients are discussed.

Varicella zoster viral disease

Herpes zoster is cause of considerable morbidity, especially among elderly patients, with a suggestion of a slight increase in incidence among female patients. Substantial research on the biology of the varicella zoster virus has led to advances in our knowledge of the pathophysiology of the disease along with more successful therapy for the acute episodes of herpes zoster. Ophthalmic zoster is more common than zoster in other cranial nerves and is associated with pronounced suffering. This article reviews the epidemiology, biology, and latency of herpes zoster, discusses the pathophysiology of the disease, and describes treatment options with antivirals and corticosteroids. The pathophysiology and treatment options for postherpetic neuralgia are also addressed. The varicella vaccine is now available, and initial results suggest that this may lessen the effect of herpes zoster in the future.