Post-licensure zoster vaccine effectiveness against herpes zoster and postherpetic neuralgia in older adults: a systematic review and meta-analysis

Herpes Zoster Ophthalmicus: Presentation, Complications, Treatment, and Prevention

Herpes zoster (HZ) is caused by reactivation of latent infection of varicella zoster virus (VZV) in sensory (cranial, dorsal root) ganglia. Major risk factors for HZ are increasing age and immunosuppression. HZ ophthalmicus (HZO) is a subset of HZ with involvement of the ophthalmic division of the fifth cranial trigeminal nerve. Approximately 4-20% of patients with HZ develop HZO. Approximately 50% of patients with HZO develop ocular disease, among whom up to 25% develop chronic or recurrent disease. Common manifestations of ocular disease include conjunctivitis, keratitis, and uveitis, whereas optic neuropathy and retinitis are uncommon. Due to the potential for vision impairment, ocular involvement requires urgent ophthalmic consultation. Early recognition and timely treatment with antivirals may prevent ocular complications. HZO is preventable by vaccination against HZ. Vaccine efficacy/effectiveness studies have been largely conducted for HZ with few studies assessing HZO. Both the recombinant adjuvanted vaccine (RZV) and live-attenuated vaccine (ZVL) significantly reduce the incidence of HZ and HZO in older adults. RZV is more effective than ZVL. Data on the effectiveness of vaccines for prevention of recurrent disease in patients with HZO are limited; however, vaccination is recommended. Despite recommendations to vaccinate individuals likely to benefit from an HZ vaccine, coverage for adults remains suboptimal. Barriers to vaccination include patient beliefs about HZ or HZ vaccines, and factors related to healthcare providers. In particular, the lack of a recommendation from their primary care physician is often cited by patients as a reason for remaining unvaccinated. By encouraging vaccination against HZ, physicians not only prevent HZ and HZO but also potential vision loss due to HZO.Graphical abstract available for this article.

Herpes zoster ophthalmicus: frequency and risk factors for developing uncommon ocular manifestations

OBJECTIVE

To determine the frequency of herpes zoster ophthalmicus (HZO) and assess risk factors for developing uncommon ocular manifestations of laboratory-verified HZO.

DESIGN

Retrospective cohort study.

METHODS

The frequency of HZO out of all herpes zoster cases was calculated using International Classification of Diseases codes for patients seen at the University of Pittsburgh Medical Center from January 1, 2004 to October 31, 2021. We also collected demographic and clinical data of patients with HZO identified by polymerase chain reaction (PCR) detection of varicella zoster virus from January 1, 2011 to December 31, 2020.

RESULTS

The frequency of HZO from 2004 to 2021 in all ages was 4.2% and ranged from 2.7% to 6.7% annually, with a consistent increase of 2.9% from 2012 to 2021. After the live zoster vaccine became available in 2008, the frequency of HZO decreased by 5.1% from 2008 to 2012 in patients aged 60 and older. Among 50 cases of PCR-verified HZO, 62% represented clinically-common ocular manifestations, mostly comprised of 13 cases of keratitis and 10 cases of anterior uveitis. Fifteen cases of acute retinal necrosis (ARN) represented the majority of uncommon HZO manifestations (38%), which were significantly more likely to occur in immunosuppressed patients (unadjusted odds ratio 4.55, 95% confidence interval 1.29-13.83).

CONCLUSIONS

The overall frequency of HZO from 2004 to 2021 was 4.2% and has increased annually since 2012. Uncommon ocular manifestations of PCR-verified HZO, mostly comprised of ARN, were more likely to occur in immunosuppressed patients.

Herpes zoster in Belgium: a new solution to an old problem

Herpes zoster (HZ) is caused by reactivation of the varicella-zoster virus. The life-time risk of developing HZ is ~ 30%. Management of HZ can be challenging due to limited efficacy of oral antivirals on pain control, and neuropathic pain that may require aggressive management. Post-herpetic neuralgia (PHN) can cause substantial pain and occurs in up to one-quarter of patients with HZ. Up to 48,000 HZ cases are estimated to occur annually in Belgium, estimated to cost almost 7 million euros in treatment. The recombinant zoster vaccine (RZV, Shingrix, GSK) was approved in Europe in 2017. In 2022, the Belgian Superior Health Council recommended vaccination with RZV for immunocompetent adults aged ≥ 60 years, and immunocompromised patients aged ≥ 16 years, including those receiving immunosuppressive therapy, in particular Janus kinase inhibitors. RZV showed high age-independent efficacy in preventing HZ infection and in clinical trials that has since been confirmed in real-world effectiveness studies. In clinical trials, protection was sustained for at least 10 years after vaccination. As of 1 November 2023, RZV is reimbursed for three immunocompromised patient groups aged ≥ 18 years: malignancy treated in the past 5 years, HIV infection, and organ or haematological stem cell transplantation or are a transplant candidate. HZ is vaccine-preventable and RZV provides a highly effective tool for HZ prevention. While reimbursement for some at-risk groups is welcomed, reimbursement currently falls well short of Superior Health Council recommendations. Adult immunisation strategies should be promoted to achieve high vaccination coverage against HZ, contributing to healthy aging in Belgium.

Assessing herpes zoster vaccine efficacy in patients with diabetes: A community-based cohort study

The effectiveness of herpes zoster (HZ) vaccines in patients with diabetes over the age of 50 remains an active area of research. Utilizing a real-world database from the US community, this study spanning from 2006 to 2023, aimed to evaluate the impact of HZ vaccination on newly diagnosed diabetes patients who received an HZ vaccination within 1 year of diagnosis. Exclusion criteria were established to omit patients with immune deficiencies. The cohort consisted of 53 885 patients, with an average age of 63.5 years, including 43% females and 58% whites. After implementing 1:1 propensity score matching for age, sex, race, comorbidities, diabetes medication, and hemoglobin A1c to ensure comparability, the study population was further stratified into four groups: N1 comparing any HZ vaccination to non-HZ vaccination (53 882 matched pairs), N2 for Shingrix versus non-HZ vaccination (16 665 matched pairs), N3 for Zostavax versus non-HZ vaccination (12 058 matched pairs), and N4 for Shingrix versus Zostavax (11 721 matched pairs). Cox proportional hazards regression analysis revealed a hazard ratio (HR) for HZ incidence post any HZ vaccination of 0.92 (95% confidence interval [CI]: 0.83-1.01). Additional analyses yielded HRs of 1.12 (95% CI: 0.93-1.34) for Shingrix versus non-HZ vaccine, 1.02 (95% CI: 0.86-1.20) for Zostavax versus non-HZ vaccine, and 1.06 (95% CI: 0.87-1.29) for Shingrix versus Zostavax. Subgroup analyses across age, sex, and follow-up duration also showed no significant differences. These findings underscore the lack of a significant benefit from HZ vaccination in newly diagnosed diabetes patients aged over 50, highlighting the necessity for further prospective research.

Time to talk to adults with rheumatic diseases about herpes zoster vaccination

The 2019 European Alliance of Associations for Rheumatology (EULAR) recommendations on herpes zoster vaccination for adult patients with rheumatic immune-mediated inflammatory diseases stated that these patients are at increased risk of herpes zoster compared with the general population. However, these recommendations lack clarity and specificity and are cautiously phrased, which might cause physicians to underestimate the importance of herpes zoster vaccination for these patients, potentially resulting in suboptimal protection. Since the formulation of the 2019 EULAR guidelines, new data on herpes zoster in patients with immune-mediated inflammatory diseases have been published. Moreover, a recombinant herpes zoster vaccine (Shingrix) has become available that can be given to these patients in a more accessible manner than the original live-attenuated vaccine (Zostavax). Here, we evaluate existing evidence on risk factors for herpes zoster and the safety and efficacy of the recombinant vaccine in patients with rheumatic immune-mediated inflammatory diseases and discuss the necessity of herpes zoster vaccination for these patients.

Preclinical immunogenicity of an adenovirus-vectored vaccine for herpes zoster

Herpes zoster (HZ) results from waning immunity following childhood infection with varicella zoster virus (VZV) but is preventable by vaccination with recombinant HZ vaccine or live HZ vaccine (two doses or one dose, respectively). Vaccine efficacy declines with age, live HZ vaccine is contraindicated in immunosuppressed individuals, and severe local reactogenicity of recombinant HZ vaccine is seen in up to 20% of older adults, indicating a potential need for new vaccines. Nonreplicating chimpanzee adenovirus (ChAd) vectors combine potent immunogenicity with well-established reactogenicity and safety profiles. We evaluated the cellular and humoral immunogenicity of ChAdOx1 encoding VZV envelope glycoprotein E (ChAdOx1-VZVgE) in mice using IFN-γ ELISpot, flow cytometry with intracellular cytokine staining, and ELISA. In outbred CD-1 mice, one dose of ChAdOx1-VZVgE (1 × 10⁷ infectious units) elicited higher gE-specific T cell responses than two doses of recombinant HZ vaccine (1 µg) or one dose of live HZ vaccine (1.3 × 10³ plaque-forming units). Antibody responses were higher with two doses of recombinant HZ vaccine than with two doses of ChAdOx1-VZVgE or one dose of live HZ vaccine. ChAdOx1-VZVgE boosted T cell and antibody responses following live HZ vaccine priming. The frequencies of polyfunctional CD4+ and CD8+ T cells expressing more than one cytokine (IFN-γ, TNF-α and IL-2) were higher with ChAdOx1-VZVgE than with the conventional vaccines. Results were similar in young and aged BALB/c mice. These findings support the clinical development of ChAdOx1-VZVgE for prevention of HZ in adults aged 50 years or over, including those who have already received conventional vaccines.

Recombinant zoster vaccine in immunocompetent and immunocompromised adults: A review of clinical studies

Herpes zoster (HZ) is a debilitating vaccine-preventable disease. Impairment of cell-mediated immunity, as observed with aging and immunosuppressive disorders and therapies, increases risk. Recombinant zoster vaccine (RZV) is efficacious against HZ in adults aged ≥50 years in different settings, and in immunocompromised adults aged ≥18 years who are at increased risk of developing HZ. RZV is the first and only HZ vaccine approved for use in immunocompromised adults globally, including in Europe and the US. RZV has a clinically acceptable safety profile and elicits robust immune responses in adults aged ≥50 years, and in immunocompromised adults aged ≥18 years who are at increased risk of HZ. Additionally, RZV is efficacious against HZ complications such as post-herpetic neuralgia and HZ-related pain. This review updates knowledge from a randomized controlled trial setting on the efficacy, safety, immunogenicity, and impact on quality of life of RZV.

Effectiveness and safety of recombinant zoster vaccine: A review of real-world evidence

The recombinant zoster vaccine (RZV) was licensed in the US for prevention of herpes zoster (HZ) in 2017. We conducted a literature search (January 1, 2017-August 1, 2023) using PubMed, Embase, and Scopus to consolidate the real-world evidence related to RZV. Overall, RZV effectiveness against HZ was high across the studied populations in real-world settings, including adults aged ≥ 50 years and patients aged ≥ 18 years with immunodeficiency or immunosuppression. Effectiveness was higher with two doses versus one dose, especially in elderly people and immunocompromised individuals. The safety profile of RZV was broadly consistent with that established in clinical trials. RZV does not appear to increase the risk of disease flares in patients with immune-mediated diseases. Approximately two-thirds of individuals received a second RZV dose within 2-6 months after the first dose. Collectively, RZV effectiveness against HZ was high, and these real-world studies reaffirm its favorable benefit-risk profile.

Pre-Clinical Development of an Adenovirus Vector Based RSV and Shingles Vaccine Candidate

Respiratory syncytial virus (RSV) infection and shingles are two viral diseases that affect older adults, and a combined vaccine to protect against both could be beneficial. RSV infection causes hospitalisations and significant morbidity in both children and adults and can be fatal in the elderly. The RSV fusion (F) envelope glycoprotein induces a strong RSV-neutralising antibody response and is the target of protective immunity in the first RSV vaccine for older adults, recently approved by the FDA. An initial childhood infection with the varicella zoster virus (VZV) results in chickenpox disease, but reactivation in older adults can cause shingles. This reactivation in sensory and autonomic neurons is characterized by a skin-blistering rash that can be accompanied by prolonged pain. The approved protein-in-adjuvant shingles vaccine induces VZV glycoprotein E (gE)-fspecific antibody and CD4+ T cell responses and is highly effective. Here we report the evaluation of RSV/shingles combination vaccine candidates based on non-replicating chimpanzee adenovirus (ChAd) vectors. We confirmed the cellular and humoral immunogenicity of the vaccine vectors in mice using T cell and antibody assays. We also carried out an RSV challenge study in cotton rats which demonstrated protective efficacy following a homologous prime-boost regimen with our preferred vaccine candidate.

Efficacy and effectiveness of Herpes zoster vaccination in adults with diabetes mellitus: a systematic review and meta-analysis of clinical trials and observational studies

AIM

The risk for Herpes zoster (HZ) and its complications is higher in people with diabetes mellitus (DM). Our aim is to assess efficacy and effectiveness of the currently available live-attenuated zoster vaccine (LZV) and recombinant zoster vaccine (RZV) in adults with DM.

METHODS

A Systematic Review and Meta-analysis of clinical trials and observational studies comparing incidence of HZ and its complications in vaccinated and unvaccinated people with DM was performed, on PubMed, Cochrane, Clinical Trials.gov and Embase databases, up to January 15th, 2023. Risk of bias was assessed through the Cochrane Collaboration tool and the Newcastle-Ottawa Scale. The protocol was registered on the PROSPERO website (CRD42022370705).

RESULTS

Only three observational studies reported LZV efficacy and effectiveness in people with DM. A lower risk for HZ infection (MH-OH Ratio 95% CI = 0.52 [0.49, 0.56] was observed, for unadjusted analysis, and 0.51 [0.46, 0.56] for adjusted analysis, both with P < 0.00001 and no heterogeneity). No data on LZV safety were reported. A pooled analysis of two trials comparing RZV and placebo, showed a reduced risk for HZ incidence: (95% CI Odds Ratio: 0.09 [0.04-0.19]), with no difference in severe adverse events and mortality.

CONCLUSIONS

In our meta-analysis of three observational studies LZV showed a 48% effectiveness in reducing HZ incidence in adults with diabetes whereas in a pooled analysis of two RCTs, RZV showed a 91% efficacy. No data are available on the effects of vaccination on the incidence and severity of HZ-related complications among subjects with diabetes.

Neuropathic Pain in the Emergency Setting: Diagnosis and Management

Neuropathic pain, traditionally considered a chronic condition, is increasingly encountered in the emergency department (ED), accounting for approximately 20% of patients presenting with pain. Understanding the physiology and key clinical presentations of neuropathic pain is crucial for ED physicians to provide optimal treatment. While diagnosing neuropathic pain can be challenging, emphasis should be placed on obtaining a comprehensive medical history and conducting a thorough clinical examination. Patients often describe neuropathic pain as a burning or shock-like sensation, leading them to seek care in the ED after ineffective relief from common analgesics such as paracetamol and NSAIDs. Collaboration between emergency medicine specialists, neurologists, and pain management experts can contribute to the development of evidence-based guidelines specifically tailored for the emergency department setting. This article provides a concise overview of the common clinical manifestations of neuropathic pain that may prompt patients to seek emergency care.

Updated Considerations for the Immunopharmacological Aspects of the "Talented mRNA Vaccines"

Messenger RNA (mRNA) vaccines belong to a new class of medications, RNA therapeutics, including both coding and non-coding RNAs. The use of mRNA as a therapy is based on the biological role of mRNA itself, namely its translation into a functional protein. The goal of mRNA vaccines is to produce a specific antigen in cells to elicit an immune response that might be prophylactic or therapeutic. The potential of mRNA as vaccine has been envisaged for years but its efficacy has been clearly demonstrated with the approval of COVID-19 vaccines in 2021. Since then, mRNA vaccines have been in the pipeline for diseases that are still untreatable. There are many advantages of mRNA vaccines over traditional vaccines, including easy and cost-effective production, high safety, and high-level antigen expression. However, the nature of mRNA itself and some technical issues pose challenges associated with the vaccines' development and use. Here we review the immunological and pharmacological features of mRNA vaccines by discussing their pharmacokinetics, mechanisms of action, and safety, with a particular attention on the advantages and challenges related to their administration. Furthermore, we present an overview of the areas of application and the clinical trials that utilize a mRNA vaccine as a treatment.

Advances and challenges in neuropathic pain: a narrative review and future directions

Over the past few decades, substantial advances have been made in neuropathic pain clinical research. An updated definition and classification have been agreed. Validated questionnaires have improved the detection and assessment of acute and chronic neuropathic pain; and newer neuropathic pain syndromes associated with COVID-19 have been described. The management of neuropathic pain has moved from empirical to evidence-based medicine. However, appropriately targeting current medications and the successful clinical development of drugs acting on new targets remain challenging. Innovative approaches to improving therapeutic strategies are required. These mainly encompass rational combination therapy, drug repurposing, non-pharmacological approaches (such as neurostimulation techniques), and personalised therapeutic management. This narrative review reports historical and current perspectives regarding the definitions, classification, assessment, and management of neuropathic pain and explores potential avenues for future research.

Factors influencing herpes zoster vaccination among older people in China: results from a discrete choice experiment

OBJECTIVES

Vaccination is the most effective way to prevent herpes zoster (HZ) and related complications. This study aimed to investigate the preference of HZ vaccine among older people.

STUDY DESIGN

A discrete choice experiment was performed.

METHODS

In total, 178 adults aged ≥50 years were invited to choose between HZ vaccination scenarios using six vaccine attributes. Two equations were used to calculate participants' willingness to pay for the vaccine and their predicted choice probability.

RESULTS

The attributes that significantly influenced participants' vaccine choices were lower cost, higher effectiveness, reduced side-effects and vaccination of others in their surroundings.

CONCLUSIONS

Improving medical insurance coverage or reducing the cost of the HZ vaccine will encourage more people to be vaccinated, resulting in reduced burden of disease among older people.

Impact of aging on immunity in the context of COVID-19, HIV, and tuberculosis

Knowledge of aging biology needs to be expanded due to the continuously growing number of elderly people worldwide. Aging induces changes that affect all systems of the body. The risk of cardiovascular disease and cancer increases with age. In particular, the age-induced adaptation of the immune system causes a greater susceptibility to infections and contributes to the inability to control pathogen growth and immune-mediated tissue damage. Since the impact of aging on immune function, is still to be fully elucidated, this review addresses some of the recent understanding of age-related changes affecting key components of immunity. The emphasis is on immunosenescence and inflammaging that are impacted by common infectious diseases that are characterized by a high mortality, and includes COVID-19, HIV and tuberculosis.

The EURO-FORTA (Fit fOR The Aged) List Version 2: Consensus Validation of a Clinical Tool for Improved Pharmacotherapy in Older Adults

BACKGROUND

The aging of our societies leads to a higher prevalence of multimorbidity and therefore polypharmacy, which often results in inappropriate drug treatment. To address this issue, numerous listing approaches, such as the Fit fOR The Aged (FORTA) list have been developed. FORTA's positive impact on the quality of medications and relevant clinical outcomes has been shown. Based on new emerging evidence and experiences with the existing FORTA lists, we aimed to update the FORTA lists in several European countries/regions.

METHODS

Two-step Delphi consensus procedures were conducted in Poland, UK/Ireland, Italy, Spain, the Nordic countries, The Netherlands and France. The existing European FORTA lists served as survey proposals.

RESULTS

Thirty-two experts agreed to take part in this study (return rate: 96.9%). The country/region-specific overall consensus for all items and participants after the first round was > 90%. FORTA lists from six participating countries, plus the FORTA list for the German-speaking countries, were collated into the new EURO-FORTA List, which now contains 267 items aligned to 27 indications. Three items were added to the EURO-FORTA List, and no drugs were deleted. Eight FORTA items were relabeled, and 96.9% of the labels remained unchanged.

CONCLUSION

In this study, seven new country/region specific FORTA lists, as well as a new overarching EURO-FORTA List, were developed. An overall increase in the mean consensus coefficient and increases for all disease-specific mean consensus coefficients show a wider consensus among participants. The new lists have the potential to improve drug therapy in older people internationally.

Vaccination in liver diseases and liver Transplantation: Recommendations, implications and opportunities in the post-covid era

The interest in vaccination efficacy and toxicity has surged following the Covid-19 pandemic. Immune responses to several vaccines have been shown to be suboptimal in patients with chronic liver disease (CLD) or post-liver transplant (LT), as a consequence of cirrhosis-associated immune dysfunction (CAID) or post-LT immunosuppression respectively. Accordingly, vaccine-preventable infections may be more common or severe than in the general population. The Covid-19 pandemic has greatly accelerated research and development into vaccination technology and platforms, which will have spillover benefits for liver patients. The aims of this review are: (i) to discuss the impact of vaccine-preventable infections on CLD and post-LT patients, (ii) to appraise current evidence supporting vaccination strategies, and (iii) to provide some insight into recent developments relevant for liver patients.

Systematic review with network meta-analysis: Risk of Herpes zoster with biological therapies and small molecules in inflammatory bowel disease

BACKGROUND

Biologics and small molecules for inflammatory bowel disease (IBD) may increase infection risk. Herpes zoster causes acute and long-term symptoms, but vaccination is not recommended in patients with IBD, unless >50 years of age.

AIMS

To examine risk of Herpes zoster infection with all licensed biologics and small molecules for IBD using network meta-analysis.

METHODS

We searched the literature to 4th October 2022, for randomised controlled trials of these drugs in luminal Crohn's disease or ulcerative colitis reporting data on occurrence of Herpes zoster infection during follow-up. We used a frequentist approach and a random effects model, pooling data as relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

We identified 25 trials (9935 patients). Only tofacitinib 10 mg b.d. (RR = 6.90; 95% CI 1.56-30.63, number needed to harm (NNH) = 97; 95% CI 19-1022) and upadacitinib 45 mg o.d. (RR = 7.89; 95% CI 1.04-59.59, NNH = 83; 95% CI 10-14,305) were significantly more likely to increase risk of Herpes zoster infection. Janus kinase inhibitors were the most likely drug class to increase risk of infection, and risk increased with higher doses (RR with lowest dose = 3.16; 95% CI 1.02-9.84, NNH = 265; 95% CI 65-28,610, RR with higher dose = 5.91; 95% CI 2.21-15.82, NNH = 117; 95% CI 39-473).

CONCLUSIONS

In a network meta-analysis, the janus kinase inhibitor tofacitinib, and all janus kinase inhibitors considered as a class, were most likely to increase risk of Herpes zoster infection. Risk increased with higher doses.

Herpes zoster vaccine effectiveness against herpes zoster and postherpetic neuralgia in New Zealand: a retrospective cohort study

BACKGROUND

Herpes zoster (HZ) and associated complications cause significant burden to older people. A HZ vaccination programme was introduced in Aotearoa New Zealand in April 2018 with a single dose vaccine for those aged 65 years and a four-year catch up for 66-80 year-olds. This study aimed to assess the 'real-world' effectiveness of the zoster vaccine live (ZVL) against HZ and postherpetic neuralgia (PHN).

METHODS

We conducted a nationwide retrospective matched cohort study from 1 April 2018 to 1 April 2021 using a linked de-identified patient level Ministry of Health data platform. A Cox proportional hazards model was used to estimate ZVL vaccine effectiveness (VE) against HZ and PHN adjusting for covariates. Multiple outcomes were assessed in the primary (hospitalised HZ and PHN - primary diagnosis) and secondary (hospitalised HZ and PHN: primary and secondary diagnosis, community HZ) analyses. A sub-group analysis was carried out in, adults ≥ 65 years old, immunocompromised adults, Māori, and Pacific populations.

FINDINGS

A total of 824,142 (274,272 vaccinated with ZVL matched with 549,870 unvaccinated) New Zealand residents were included in the study. The matched population was 93.4% immunocompetent, 52.2% female, 80.2% European (level 1 ethnic codes), and 64.5% were 65-74 years old (mean age = 71.1±5.0). Vaccinated versus unvaccinated incidence of hospitalised HZ was 0.16 vs. 0.31/1,000 person-years and 0.03 vs. 0.08/1000 person-years for PHN. In the primary analysis, the adjusted overall VE against hospitalised HZ and hospitalised PHN was 57.8% (95% CI: 41.1-69.8) and 73.7% (95% CI:14.0-92.0) respectively. In adults ≥ 65 years old, the VE against hospitalised HZ was 54.4% (95% CI: 36.0-67.5) and VE against hospitalised PHN was 75·5% (95% CI: 19.9-92.5). In the secondary analysis, the VE against community HZ was 30.0% (95% CI: 25.6-34.5). The ZVL VE against hospitalised HZ for immunocompromised adults was 51.1% (95% CI: 23.1-69.5), and PHN hospitalisation was 67.6% (95% CI: 9.3-88.4). The VE against HZ hospitalisation for Māori was 45.2% (95% CI: -23.2-75.6) and for Pacific Peoples was 52.2% (95% CI: -40.6 -83·7).

INTERPRETATION

ZVL was associated with a reduction in risk of hospitalisation from HZ and PHN in the New Zealand population.

FUNDING

Wellington Doctoral Scholarship awarded to JFM.

Prevention of Herpes Zoster: A Focus on the Effectiveness and Safety of Herpes Zoster Vaccines

Infection with varicella zoster virus typically occurs in children and it can cause primary varicella infection or "chickenpox", or it can reactivate later in life and cause herpes zoster or "shingles". Herpes zoster mainly occurs in older adults, causing a reduction in activities of daily living, impacting quality of life, and may lead to serious complications, including chronic pain. Two vaccines are marketed to prevent herpes zoster: the live zoster vaccine and the non-live, recombinant zoster vaccine. The pre-licensure clinical trials show the efficacy of the live zoster vaccine to be between 50 and 70% and for the recombinant vaccine to be higher at 90 to 97%. Real-world effectiveness studies, with a follow-up of approximately 10 years, were reviewed in this article. These data corroborated the efficacy studies, with vaccine effectiveness being 46% and 85% for the live and recombinant vaccines, respectively. Safety data from the effectiveness studies show similar results to the clinical trials with mostly local injection-site reactions and mild systemic reactions seen with both vaccines, although in larger proportions with the recombinant vaccine. Rare adverse events, occurring less than 1% of the time, have been seen with both vaccine types and include disseminated herpes zoster with the live zoster vaccine and Guillain-Barré syndrome with the recombinant vaccine. The wider use of preventative measures with vaccines will reduce the herpes zoster burden of illness seen in older adults.