Varicella zoster virus infection: clinical features, molecular pathogenesis of disease, and latency

A fresh look at varicella vaccination

The varicella vaccine is a live attenuated varicella zoster virus (VZV), first produced by Michiaki Takahashi (1974). Subsequent development of the fluorescent antibody to VZV membrane antigen test (FAMA), an immune correlate, permitted vaccine efficacy to be established, initially in immunodeficient and then in typical children and adults. Varicella vaccine is effective and safe; universal vaccination has almost eliminated varicella; moreover, endogenous boosting from subclinical VZV reactivation has evidently prevented an anticipated epidemic of zoster from occurring in response to the vaccine-induced loss of circulating varicella. The vaccine virus, moreover, reactivates less frequently than wild-type and an adjuvanted subunit vaccine against VZV gE safely prevents zoster. Doing so is important because VZV establishes latency and reactivates in sympathetic and enteric neurons; therefore, in addition to the painful cutaneous rash and postherpetic neuralgia of zoster, VZV reactivation can be an occult cause of vasculopathy, stroke, intestinal dysmotility, and achalasia.

Age-related changes in the immune system and challenges for the development of age-specific vaccines

BACKGROUND

A better understanding of how the immune system evolves with age and how vaccines work in older people has led to increasing focus on the development of vaccines aimed specifically at older age groups. We discuss strategies used to improve vaccine immunogenicity for older adults, focusing on licensed adjuvants.

FINDINGS

With age-related immune decline (immunosenescence), older adults face increased vulnerability to infections and severe complications. Immunosenescence affects T-cell and B-cell populations and innate immunity, leading to reduced chemotaxis, cytotoxicity, and altered cytokine production. This contributes to inflammaging-low-grade, chronic inflammation linked to aging. However, immune responses vary due to genetics and life-long exposures, making chronological age an imperfect indicator of immune health. Vaccination remains key to prevention, yet immune dysfunction complicates vaccine efficacy. Strategies to enhance responses in older adults include mRNA vaccines, high-antigen content vaccines, intradermal administration, and adjuvants. mRNA COVID-19 vaccines generated strong immune responses in older adults, though lower than in younger groups. High-antigen content influenza vaccines have shown superior efficacy compared to standard vaccination. Adjuvants offer a well-established approach to boosting vaccine responses by enhancing innate immunity.

CONCLUSIONS

Of various strategies used to improve immunogenicity of vaccines for older adults, adjuvants have been the most consistently effective and practical. More recently, mRNA vaccines have also shown great promise.

A Photodermatologic Perspective on Shingles: A Narrative Review Exploring the Skin Microbiome as a Variable in the Effect of UV Radiation on VZV Reactivation

Varicella Zoster Virus (VZV), a member of the herpes virus family, causes varicella (chicken pox) upon primary infection and later manifests as herpes zoster ([HZ] or shingles) upon reactivation. VZV-specific T-cell immunity acquired during primary infection aids recovery, with the virus lying latent in neuronal ganglia until it transports to the skin axonally during reactivation. It has been well-established that reduced T-cell recognition and proliferation, as well as immunosuppression more generally, contribute to VZV reactivation. It has also been discovered that seasonal variation, which is linked to ultraviolet radiation (UVR), correlates with increased HZ cases. This correlation may be explained by the direct immunosuppressant effects of UVR, with melanin offering photoprotective effects that decrease reactivation rates. However, an underexplored aspect of this correlation is the potential role of the skin microbiome in UVR-induced VZV reactivation. Vital for skin homeostasis and immune modulation, the skin microbiome has been found to influence various skin conditions. Preliminary evidence suggests that microbiome diversity may influence VZV reactivation rates, supported by antibiotic-induced effects on HZ incidence. Research also indicates the microbiome's modulating effect on UVR-induced immune suppression, emphasizing its potential significance in VZV reactivation. The skin microbiome's contribution may also help further explain sex and ethnicity-specific variations in VZV reactivation rates. Understanding the interplay between UVR, the skin microbiome, and VZV reactivation warrants further investigation and may help uncover preventive strategies for mitigating VZV reactivation.

Clinical characteristics and treatment of varicella zoster virus central nervous system infection in an Australian tertiary hospital

BACKGROUND AND AIM

Varicella zoster virus (VZV) is a neurotropic herpesvirus. With improved access to molecular diagnostics, there is increasing recognition of VZV with central nervous system involvement. This study aimed to describe the demographic, clinical and treatment characteristics of patients admitted to an Australian tertiary hospital with VZV central nervous system infection.

METHODS

Retrospective study of all adult patients (aged ≥18 years) presenting to an Australian tertiary hospital between November 2010 and May 2023 with a clinical syndrome of or imaging consistent with meningitis or encephalitis and detectable VZV DNA in cerebrospinal fluid using polymerase chain reaction.

RESULTS

There were 48 cases of VZV meningitis and 13 cases of VZV encephalitis identified during the study period. The median age of patients with VZV meningitis and encephalitis was 34 years (range 21-86 years) and 73 years (range 22-94 years) respectively. All patients with VZV encephalitis and 37 of 48 (77.1%) with meningitis received intravenous (IV) acyclovir. Eight patients with VZV meningitis were treated with oral antivirals alone and seven were managed without antivirals or with ≤48 h of empiric antiviral therapy only; none of these patients experienced an adverse clinical outcome. Two patients with VZV encephalitis died. Seven patients experienced neurological complications, three with VZV meningitis and four with VZV encephalitis. Age and length of stay were associated with adverse clinical outcomes.

CONCLUSION

VZV encephalitis predominates in older patients while VZV meningitis predominates in younger patients. IV acyclovir remains the standard of care for treatment of VZV encephalitis; however, its role in VZV meningitis is less clear. Controlled trials should be conducted to inform its use, particularly in low-risk patients with VZV meningitis.

Herpes zoster vaccination coverage and factors associated among adults aged 40 and older in China: A population-based survey

OBJECTIVES

Herpes zoster (HZ) is a significant public health issue in China, especially with an aging population and rising incidence. While vaccination effectively prevents HZ and its complications, national data on HZ vaccine (HZV) coverage and associated factors in China are limited.

METHODS

We conducted a nationwide survey across 25 provinces in mainland China, including 14,315 participants aged over 40 years, to estimate HZV uptake and associated factors among adults aged 40 years and older. Multivariate logistic regression was used to assess characteristics linked to vaccination, and we analysed vaccine types and dose completion rates.

RESULTS

The HZV uptake rate was 0.79 %. Vaccination was more likely among individuals with middle school education and higher household income. Most vaccinated individuals received the zoster vaccine live (ZVL) rather than the recombinant zoster vaccine (RZV), and nearly half completed two doses.

CONCLUSIONS

HZV coverage in China is low, underscoring the need for targeted public health strategies to improve vaccine accessibility and awareness, particularly among at-risk groups, to reduce HZ-related burdens.

Herpes zoster stromal disciform keratitis associated with endotheliitis in a 35-week pregnant woman

Herpes zoster keratitis is a common manifestation of the varicella zoster virus. The active virus can cause epithelial keratitis early in the disease course, meanwhile later in the disease course, an inflammatory response can cause stromal or endothelial keratitis. A middle-aged pregnant woman exhibited classic ocular signs associated with Herpes's stromal disciform keratitis of the left eye, including focal disk-shaped edema, descemet's folds, keratic precipitates, diminished corneal sensations, and Wessley's immune ring. The patient was symptomatic with severe left eye pain, lacrimation, photophobia, and hand-motion visual acuity. To the best of our knowledge, this case represents the first report and an interesting favorable outcome of herpes zoster stromal disciform keratitis management in an Indigenous Australian.

Immune Dysregulation in Acute Herpes Zoster: Predictive Factors for Postherpetic Neuralgia

BACKGROUND Postherpetic neuralgia (PHN) is closely related to the host immune response. This study explored the cellular and humoral immune functions of acute immunocompetent herpes zoster (HZ) patients and their relationship with PHN. MATERIAL AND METHODS We selected 188 patients with acute HZ admitted to our hospital and 79 individuals who underwent physical examinations during the same period. We measured and compared the levels of peripheral blood lymphocyte subsets (CD3+, CD4+, CD8+, CD4+/CD8+, CD19+, CD56+), serum immunoglobulins (IgA, IgG, IgM), and complement (C3, C4) between the 2 groups. Based on whether they had neuralgia during follow-up, we divided the patients into an HZ-PHN group and an HZ-control group, and compared their differences in immune functions and their relationship with PHN. RESULTS Compared with the control group, the levels of CD3+ and CD4+ and CD4+/CD8+ ratios of HZ patients were significantly lower (P<0.05). Among 188 HZ patients, 91 (48.4%) developed PHN. The patients in the HZ-PHN group were significantly older (P<0.01) and the levels of CD3+, CD4+, and CD8+ and CD4+/CD8+ ratios were significantly lower than those in the HZ-control group (P<0.05, P<0.01). Binary logistic regression analysis showed that age and CD4+/CD8+ ratios are independent risk factors for determining whether HZ patients develop PHN. CONCLUSIONS Acute immunocompetent HZ patients, especially those who are older and more prone to developing PHN, exhibit significant cellular immune dysregulation. Age and CD4+/CD8+ ratios may be useful predictors of PHN in acute HZ patients.

Metformin Against Herpes Zoster in Colon Cancer Patients with Type 2 Diabetes: A PSM Analysis

Background: Herpes zoster is a significant complication in cancer patients, particularly those with compromised immune systems. Previous studies have established the incidence of herpes zoster in gastrointestinal cancer patients, but there is a lack of specific analysis on colorectal cancer patients and the potential preventive role of metformin. This study aims to fill this gap by evaluating metformin's protective effects against herpes zoster in colon cancer patients with type 2 diabetes mellitus (T2DM). Methods: The study cohort comprised 1,510 T2DM colon adenocarcinoma patients without distant metastasis who received standard treatments from Taiwan Cancer Registry Database. Propensity score matching (PSM) was employed to balance covariates between metformin users and nonusers. Herpes zoster infection risk was assessed using Cox regression models and incidence rate calculations. The dose-dependent effects of metformin were analyzed based on cumulative defined daily doses (cDDD). Results: Metformin use was associated with a significantly reduced risk of herpes zoster infection (adjusted hazard ratio [aHR].: 0.69, 95% confidence interval [CI].: 0.51 to 0.93). A dose-dependent relationship was observed, with progressively lower aHRs across cDDD quartiles (p for trend < 0.0001). After adjusting for competing mortality risks, the aHR remained significantly lower (aHR: 0.70, 95% CI: 0.51 to 0.65). Metformin users had lower incidence rates and incidence rate ratios (IRR) of herpes zoster infection compared to nonusers (IRR: 0.75, 95% CI: 0.56 to 0.97). Conclusions: We are the first to demonstrate a dose-dependent protective effect of metformin against herpes zoster in colorectal cancer patients. Our findings indicate that higher doses of metformin correlate with a greater reduction in the risk of herpes zoster.

Elderly Female with Cranial Polyneuropathy

The recrudescence of Varicella Zoster Virus in the head and neck region often manifests as Ramsay Hunt Syndrome, characterised by facial nerve palsy, vesicular rash in the distribution of facial nerve and neuralgia. Rarely it causes cranial polyneuropathy (CP). We present a case of herpes zoster with CP, highlighting the diagnostic challenges and management in a resource-limited setting.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-024-05211-8.

Modelled Public Health Impact of Introducing Adjuvanted Recombinant Zoster Vaccine into the UK National Immunisation Programme

INTRODUCTION

In 2023, recombinant zoster vaccine (RZV) replaced zoster vaccine live (ZVL) vaccine in the UK National Immunisation Programme (NIP) for prevention of herpes zoster (HZ). The vaccination age was reduced from 70 to 65 years, with a subsequent planned reduction to 60 years. This modelling study aimed to evaluate the public health impact (PHI) of RZV vaccination in the 70 years of age (YOA) population and in younger individuals 65 and 60 YOA.

METHODS

PHI was evaluated from a National Health Service perspective, as cases of HZ, post-herpetic neuralgia (PHN), non-PHN complications and deaths, hospitalisations, and general practitioner (GP) visits avoided using a multicohort Markov model. Three scenarios (RZV vs. no vaccination, ZVL vs. no vaccination, and RZV vs. ZVL) were explored for each age group using population estimates from the UK Office for National Statistics, i.e. 70 YOA (n = 649,822), 65 YOA (n = 760,578) and 60 YOA (n = 849,501).

RESULTS

Modelled outcomes in 70 YOA individuals estimated that RZV vaccination would avoid 32,894 cases of HZ and 5915 cases of PHN compared with no vaccination and 26,954 HZ and 3218 PHN cases compared with ZVL. Compared with no vaccination, 2264 fewer hospitalisations and 158,549 fewer GP visits were predicted with RZV vaccination. Hospitalisations were predicted to be reduced by 1996 and GP visits by 130,821 for RZV versus ZVL vaccination. In individuals 65 YOA, it was estimated that RZV vaccination would avoid 50,128 HZ cases, 8623 PHN cases, 222,646 GP visits, and 2671 hospitalisations versus no vaccination. In the 60 YOA group, RZV vaccination was predicted to avoid 57,182 HZ cases, 9327 PHN cases, 234,330 GP visits, and 2547 hospitalisations versus no vaccination.

CONCLUSION

The recent introduction of RZV into the NIP could substantially reduce HZ disease burden and healthcare resource use in the UK. A graphical abstract is available with this article.

The public health impact of recombinant herpes zoster vaccination in adults over 50 years in Spain

The recombinant zoster vaccine (RZV) is included in the Spanish National Immunisation Programme for adults 65 years of age (years), with a potential progressive catch-up program for adults 66-80 years, starting with 80 years. However, the risk of herpes zoster (HZ) increases significantly from 50 years. We estimated the public health impact (PHI) of vaccinating adults ≥50 years in Spain versus no vaccination, using a Markov model adapted to the Spanish setting. The model simulated a hypothetical ≥50 years cohort over a lifetime, with inputs from Spanish publications, databases, or publications from other countries where Spanish data were unavailable. Base case inputs included 67.7% RZV coverage and 61.1% second dose compliance. Outputs included clinical outcomes avoided, healthcare resource use avoided, and number-needed-to-vaccinate (NNV) to prevent one HZ case. Deterministic (DSA) and probabilistic sensitivity analyses (PSA) were also conducted. The model estimated that, compared with no vaccination, vaccinating adults ≥50 years in Spain (N = 19,850,213) with RZV could prevent 1,533,353 HZ cases, 261,610 postherpetic neuralgia episodes, 274,159 other complications, and 138 deaths through the cohorts' remaining lifetime, mostly in the 50-59 years cohort. Furthermore, 3,500,492 primary care visits and 71,156 hospitalizations could be avoided, with NNV = 9 to prevent one HZ case. DSA predicted NNV = 7 to prevent one HZ case when second dose compliance was increased to 100%. PSA demonstrated ≥200,000 and ≥1,400,000 cases could be prevented in 86.9% and 18.4% of simulations, respectively. Starting RZV from 50 years could therefore prevent a substantial number of HZ cases and complications. Increasing RZV coverage and second dose compliance could further alleviate PHI of HZ.

A prospective, multi-center post-marketing surveillance cohort study to monitor the safety of the recombinant zoster vaccine in Chinese adults ≥50 years of age

This post-marketing surveillance study evaluated the safety of the adjuvanted recombinant zoster vaccine (RZV) in Chinese adults, given the limited country-specific safety data accumulated since the 2019 licensure of RZV in China for adults ≥ 50 years of age (YOA). This descriptive, prospective cohort study enrolled adults ≥ 50 YOA who voluntarily received RZV per routine clinical practice in six centers in China. The primary outcomes were occurrence, intensity, and causal relationship to vaccination of medically attended adverse events (MAEs) within 30 days post-any dose. The occurrence and causal relationship to RZV of serious AEs (SAEs) within 30 days post-any dose, and of SAEs and potential immune-mediated diseases (pIMDs) from dose 1 until 12 months post-last dose were secondary outcomes. The exposed set included 3,300 adults (mean age [standard deviation]: 61.2 [7.4] years; 67.1% female), of whom 3,175 completed the study. Fifty-six MAEs were recorded in 42 (1.3%, 95% confidence interval [CI]: 0.9-1.7%) participants; ≥1 grade 3 MAE was reported in six (0.2%, 0.1-0.4%) participants; 15 MAEs (in nine [0.3%, 0.1-0.5%] participants) were considered RZV-related. Within 30 days post-any dose, 12 SAEs were reported in 10 (0.3%, 0.1-0.6%) participants, while 29 SAEs in 22 (0.7%, 0.4-1.0%) participants were reported from post-dose 1 until 12 months post-last dose. The three reported fatal SAEs were not considered RZV-related. Three of the total seven pIMDs were considered RZV-related. The observed descriptive patterns of MAEs, SAEs, and pIMDs did not indicate safety concerns following RZV administration among Chinese adults ≥ 50 YOA.

Expanded spectrum of varicella disease and the need for vaccination in India

Varicella vaccine was first licensed in Japan and South Korea in 1989 for use in healthy children and was introduced in US in 1995. So far, 29 countries have adopted varicella vaccine in their universal immunization program (UIP). No Asian country, India included, has adopted the varicella vaccine as part of their UIP. The extra-cutaneous sites for VZV diseases are central nervous system and gastrointestinal tract, the expanded disease spectrum includes vasculopathy, myelitis, inflammatory bowel disease, perforated ulcers, and gastritis. The actual disease burden of varicella is not known as most of the infected individuals may not visit the physician. The amplifiable VZV DNA will not always be detectable in cerebrospinal fluid (CSF) samples in protracted illnesses such as vasculopathies, but demonstrable anti-VZV IgG in CSF has diagnostic value. The World Health Organization (WHO) position paper 2014 recommends two doses of varicella and zoster vaccines in targeted population. In India, varicella vaccine is not included in the UIP due to the cost and the belief that lifelong immunity occurs following primary infection. The expanded spectrum of VZV disease and the mounting body of evidence, however, suggest the need for both varicella and zoster vaccines in routine immunization schedule.

A Better Understanding of the Clinical and Pathological Changes in Viral Retinitis: Steps to Improve Visual Outcomes

Infectious retinitis, though rare, poses a significant threat to vision, often leading to severe and irreversible damage. Various pathogens, including viruses, bacteria, tick-borne agents, parasites, and fungi, can cause this condition. Among these, necrotizing herpetic retinitis represents a critical spectrum of retinal infections primarily caused by herpes viruses such as varicella-zoster virus (VZV), herpes simplex virus (HSV), and cytomegalovirus (CMV). This review underscores the retina's susceptibility to viral infections, focusing on the molecular mechanisms through which herpetic viruses invade and damage retinal tissue, supported by clinical and preclinical evidence. We also identify existing knowledge gaps and propose future research directions to deepen our understanding and improve therapeutic outcomes.

Clinical profile of herpes zoster-related hospitalizations and complications: A French population-based database study

OBJECTIVE

To estimate the incidence of hospitalization with a diagnosis of herpes zoster (HZ) and post-herpetic neuralgia (PHN) in France between 2013 and 2020, overall and stratified by age-group and immune status.

METHODS

Retrospective observational, database study, using the French hospital discharge database, which includes private and public data for all day-care and inpatient stays. Adults aged ≥18 years, hospitalized between January 1, 2013, and December 31, 2020, with a diagnosis of HZ or PHN, were included.

RESULTS

Overall, 62 077 adults had a first hospitalization with a diagnosis of HZ or PHN during the observation period. HZ and/or PHN incidence ranged between 14.6 and 16.3 hospitalizations/100 000 persons and was highest in people aged ≥80 years (97.6 hospitalizations/100 000 persons). The immunocompromised (IC) population accounted for 22% of the overall study population. IC patients had longer lengths of stay for HZ per episode compared with non-IC patients (15.5 ± 19.4 days vs 12.2 ± 13.5 days) and higher in-patient mortality (8% vs 4%). Average annual hospitalization costs per patient were higher in the IC vs non-IC population (€8018 vs €5603).

CONCLUSIONS

Older age increases hospitalization rates up to 6-fold and IC status increases in-patient mortality up to two-fold.

CLINICAL TRIAL REGISTRATION

The study was conducted by HEVA and data were provided by ATIH according to French regulatory and data protection procedures.

The inactivated herpes zoster vaccine HZ/su induces a varicella zoster virus specific cellular and humoral immune response in patients on dialysis

BACKGROUND

To evaluate the immunogenicity of the inactivated herpes-zoster vaccine HZ/su in patients at increased risk for VZV-reactivation, we analysed the quantity and quality of the vaccine-induced cellular and humoral immunity in patients on dialysis with uremic immunodeficiency.

METHODS

In this observational study, 29 patients and 39 immunocompetent controls underwent standard dual-dose vaccination. Blood samples were analysed before and two weeks after each vaccination, and after one year. Specific T-cells were characterized after stimulation with VZV-gE-peptides based on induction of cytokines and CTLA-4-expression using flow-cytometry. Antibodies were analysed using ELISA.

FINDINGS

Both groups showed an increase in VZV-gE-specific CD4 T-cell levels over time (p < 0.0001), although median levels reached after second vaccination were lower in patients (0.17% (IQR 0.21%)) than in controls (0.24% (IQR 0.3%), p = 0.042). VZV-gE specific CD8 T-cells were only poorly induced. CTLA-4 expression on VZV-gE-specific CD4 T-cells was strongest after second dose with no differences between the groups (p = 0.45). Multifunctional cells co-expressing IFNγ, IL-2, and TNF were higher in patients after first vaccination (p = 0.028). Median VZV-specific IgG-levels reached a maximum after second vaccination with significantly lower levels in patients (10796 (IQR 12482) IU/l) than in controls (16899 (IQR 14019) IU/l, p = 0.009). Despite similar CD4 T-cell levels after one year (p = 0.415), antibody levels remained significantly lower in patients (p = 0.0008).

INTERPRETATION

VZV-gE vaccination induced specific antibodies and CD4 T-cells in both patients and controls, whereas CD8 T-cell-induction was poor. Quantitative and qualitative differences in immunity may indicate reduced duration of protection which may necessitate booster vaccinations in patients on dialysis.

FUNDING

HOMFORexzellent (to D.S.).

Varicella zoster virus meningoencephalitis presenting as orbital myositis - a case report

The authors present a case of meningoencephalitis caused by Varicella zoster virus (VZV) infection, which initially manifested as orbital myositis followed by rapid progression to orbital apex syndrome, meningoencephalitis and death. There was no development of a cutaneous rash. An orbital biopsy demonstrated VZV infection, which was confirmed on a lumbar puncture. In this case, VZV meningoencephalitis was not responsive to steroid or antiviral therapy. This case highlights an atypical presentation of VZV with orbital myositis preceding intracranial involvement.

Ambispective epidemiological observational study of varicella-zoster virus infection: An 18 year-single-center Bulgarian experience

BACKGROUND

Varicella (chickenpox) and herpes zoster (shingles) are outcomes of varicella-zoster virus (VZV) infection, and understanding their incidence trends is vital for public health planning.

AIM

To conduct an ambispective epidemiological study by analyzing the main epidemiological characteristics of VZV infection during an 18 year-period (2000-2018).

METHODS

We used descriptive and epidemiological methods to characterize chickenpox in Bulgaria, the city of Plovdiv and the region for a period of 18 years (2000-2018).

RESULTS

The average incidence of varicella-zoster infection for the period 2000-2018 in the Plovdiv region was estimated at 449.58‰. The highest relative share of the infection was assessed in the month of January at 13.6%, and the lowest in the months of August and September at 2.9% (both months). The age group most affected by the infection was 1-4 years, followed by 5-9 years. This corresponds to the so-called "pro-epidemic population" - a phenomenon typical for airborne infections, confirming their mass impact on the perpetuation of VZV infection.

CONCLUSION

Our findings reveal significant insights into VZV epidemiology, including age-specific incidence rates, clinical manifestations, and vaccination impact. This comprehensive analysis contributes to the broader understanding of VZV infection dynamics and may inform evidence-based preventive measures.

Factors Influencing Herpes Zoster Vaccine Utilization Among Adults Aged 50 and Above Attending Primary Healthcare Center in Saudi Arabia: A Cross-Sectional Study

INTRODUCTION

Herpes zoster, or shingles, is a significant health concern for older adults caused by the varicella-zoster virus (VZV) reactivation. The availability of effective herpes zoster vaccines offers a crucial preventive measure to reduce the incidence and severity of this condition. However, the uptake of the available vaccine remains suboptimal, especially among adults aged 50 and above. Understanding the factors that influence vaccine utilization is not only essential for developing strategies to improve vaccination rates but also has the potential to significantly reduce the disease burden.

METHODS

This cross-sectional study aimed to identify factors influencing herpes zoster vaccine utilization among adults aged 50 and above attending primary healthcare center in Saudi Arabia. Data were collected using a validated questionnaire administered to visitors attending Al-Wazarat Primary Healthcare Center in Riyadh. Descriptive and inferential statistics were employed to analyze the data.

RESULTS

A total of 403 participants were included in the study, with 73.7% of participants having heard of the disease, yet only 34.2% had received the vaccine. Vaccine uptake was significantly associated with gender, educational level, and healthcare provider recommendations. Common barriers to vaccination included fear of side effects, lack of perceived susceptibility, concerns about vaccine effectiveness, and access to healthcare facilities.

CONCLUSION

Herpes zoster vaccine utilization among older adults in Saudi Arabia is relatively low despite moderate awareness. Enhancing public education through targeted campaigns and strengthening healthcare provider recommendations are crucial to improving vaccine uptake. Addressing specific barriers and misconceptions is essential to reduce the burden of herpes zoster in this population. The need for future research to explore strategies to overcome these challenges and promote higher vaccination rates is urgent and important.

Reduced unilateral sweating caused by varicella zoster virus infection: a case report

BACKGROUND

Herpes zoster is an infectious skin disease caused by the reactivation of the varicella zoster virus (VZV), which has been latent in the posterior root ganglia of the spinal cord or cranial ganglia for an extended period. Neurological complications caused by herpes zoster include aseptic meningitis, white matter disease, peripheral motor neuropathy, and Guillain-Barré syndrome. However, reduced unilateral sweating caused by the VZV is very rare.

CASE PRESENTATION

This article reports the case of a 34-year-old woman who was admitted to our hospital with sore throat, dizziness, and reduced sweating on the left side of her body. Physical examination found herpes lesions on the left upper lip and left external ear canal (scabbed) and reduced sweating on the left side of the body. Head magnetic resonance imaging (MRI) with contrast showed no abnormalities. After a lumbar puncture, the patient was diagnosed with viral meningitis by VZV infection. The electromyographic skin sympathetic reflex indicated damage to the left sympathetic nerve.

CONCLUSIONS

Secondary unilateral sweating reduction is a rare neurological complication of herpes zoster, caused by damage to the autonomic nervous system. Literature review and comprehensive examination indicated that the reduced unilateral sweating was due to the activation of latent herpes zoster virus in the autonomic ganglia which has damaged the autonomic nervous system. For patients who exhibit acute hemibody sweat reduction, doctors should consider the possibility of secondary autonomic nervous system damage caused by herpes zoster.

Osteonecrosis of the Jaws Associated with Herpes Zoster Infection: A Systematic Review and a Rare Case Report

The investigation's goal was to obtain further knowledge about the connection between Herpes Zoster infection and dentistry therapy for the osteonecrosis of the jaws, combining the review with a case report relevant to the purpose. It is important to study this association because it is a possible additional factor to be considered in the causes of the osteonecrosis of the jaws. We limited our search to English-language papers published between 1 January 2004 and 7 June 2024 in PubMed, Scopus, and Web of Science that were relevant to our topic. In the search approach, the Boolean keywords "Herpes Zoster AND osteonecros*" were used. Results: This study analyzed 148 papers from Web of Science, PubMed, and Scopus, resulting in 95 articles after removing duplicates. Of these, 49 were removed because they were off topic, and 46 were confirmed. This study includes a qualitative analysis of the final 12 articles, removing 34 articles that were off topic. The literature highlights severe oral complications from Herpes Zoster reactivation, emphasizing the need for early diagnosis, comprehensive management, and multidisciplinary care. Treatment strategies include antiviral therapy, pain management, surgical debridement, and antibiotics. Immunocompromised individuals require vigilant monitoring and balanced immunosuppressive therapy. Further research is needed to enhance therapeutic approaches.

Identification and characterization of Varicella Zoster Virus circular RNA in lytic infection

This study investigates the role of circular RNAs (circRNAs) in the context of Varicella-Zoster Virus (VZV) lytic infection. We employ two sequencing technologies, short-read sequencing and long-read sequencing, following RNase R treatment on VZV-infected neuroblastoma cells to identify and characterize both cellular and viral circRNAs. Our large scanning analysis identifies and subsequent experiments confirm 200 VZV circRNAs. Moreover, we discover numerous VZV latency-associated transcripts (VLTs)-like circRNAs (circVLTslytic), which contain multiple exons and different isoforms within the same back-splicing breakpoint. To understand the functional significance of these circVLTslytic, we utilize the Bacteria Artificial Chromosome system to disrupt the expression of viral circRNAs in genomic DNA location. We reveal that the sequence flanking circVLTs' 5' splice donor plays a pivotal role as a cis-acting element in the formation of circVLTslytic. The circVLTslytic is dispensable for VZV replication, but the mutation downstream of circVLTslytic exon 5 leads to increased acyclovir sensitivity in VZV infection models. This suggests that circVLTslytic may have a role in modulating the sensitivity to antiviral treatment. The findings shed new insight into the regulation of cellular and viral transcription during VZV lytic infection, emphasizing the intricate interplay between circRNAs and viral processes.

Efficacy and safety of therapies related to acupuncture for acute herpes zoster: A PRISMA systematic review and network meta-analysis

BACKGROUND

Herpes zoster (HZ) is mainly characterized by intense pain and severe skin lesions, particularly during the acute phase, which seriously affects the patient's quality of life. Acupuncture is a widely used and effective treatment for HZ. However, there are many types of acupuncture, which have different curative efficacy. This study employed a network meta-analysis (NMA) to assess and rank the clinical efficacy of different acupuncture therapies.

METHODS

The database of Cochrane Library, Web of Science, PubMed, MEDLINE, Embase, China National Knowledge Infrastructure (CNKI), Chinese BioMedical Database, VIP Database, and Wanfang Database were searched from inception to December 31, 2022 to identify eligible randomized controlled trials (RCTs) of acupuncture related therapies in the treatment of acute HZ. The outcome indicators measured were visual analogue scale (VAS), date of cessation of herpes increase (DCHI), effective rate (ER), postherpetic neuralgia (PHN), and adverse events (AEs). Bayesian network meta-analyses were performed using the GeMTC package (version 1.0-1) and R software (version 4.2.3).

RESULTS

A total of 59 RCTs with 3930 patients were included. The results of this NMA were as follows: compared with pharmacotherapy, electroacupuncture (EA) + pricking and cupping (PC) shown the best efficacy to improve VAS score and reduce DCHI. In terms of ER, EA + fire needle (FN) had the highest results of probability ranking. PC was more effective in reducing the incidence of PHN. Furthermore, this study shown that the incidence of AEs associated with acupuncture-related therapies was acceptable.

CONCLUSIONS

This study indicated that therapies related to acupuncture were both effective and safe in treating acute HZ, and could significantly reduce patients' symptoms such as pain and skin lesions with fewer adverse events. Clinically, the selection of the appropriate therapy should be based on practical considerations. However, due to the limitations of this study, more high-quality trials are required to evaluate the efficacy and safety of acupuncture-related therapy for the treatment of acute HZ.

Clinical and Economic Burden of Antibiotic Use Among Pediatric Patients With Varicella Infection in the Outpatient Setting: A Retrospective Cohort Analysis of Real-world Data in France

BACKGROUND

Varicella infects 90% of children before age 9. Though varicella is self-limiting, its complications may require antibiotics, though how antibiotics are utilized for varicella in France is not well known. This study assessed antibiotic use and costs associated with varicella and its complications in pediatric patients managed in the outpatient setting in France.

METHODS

A retrospective cohort study using the Cegedim Strategic Data-Longitudinal Patient Database, an electronic medical record database from general practitioners and office-based specialists in France, was conducted. Children <18 years old diagnosed with varicella between January 2014 and December 2018 with 3-month follow-up available were included. We used descriptive analysis to assess varicella-related complications, medication use, healthcare resource utilization and costs.

RESULTS

Overall, 48,027 patients were diagnosed with varicella; 15.3% (n = 7369) had ≥1 varicella-related complication. Antibiotics were prescribed in up to 25.1% (n = 12,045/48,027) of cases with greater use in patients with complications (68.1%, n = 5018/7369) compared with those without (17.3%, n = 7027/40,658). Mean medication and outpatient varicella-related costs were €32.82 per patient with medications costing a mean of €5.84 per patient; antibiotics contributed ~23% to total costs annually.

CONCLUSION

This study showed high antibiotic use for the management of varicella and its complications. A universal varicella vaccination program could be considered to alleviate complications and associated costs in France.

Oncolytic varicella-zoster virus engineered with ORF8 deletion and armed with drug-controllable interleukin-12

BACKGROUND

The varicella-zoster virus (VZV), belonging to the group of human α-herpesviruses, has yet to be developed as a platform for oncolytic virotherapy, despite indications from clinical case reports suggesting a potential association between VZV infection and cancer remission.

METHODS

Here, we constructed oncolytic VZV candidates based on the vaccine strain vOka and the laboratory strain Ellen. These newly engineered viruses were subsequently assessed for their oncolytic properties in the human MeWo melanoma xenograft model and the mouse B16-F10-nectin1 melanoma syngeneic model.

RESULTS

In the MeWo xenograft model, both vOka and Ellen exhibited potent antitumor efficacy. However, it was observed that introducing a hyperfusogenic mutation into glycoprotein B led to a reduction in VZV's effectiveness. Notably, the deletion of ORF8 (encodes viral deoxyuridine triphosphatase) attenuated the replication of VZV both in vitro and in vivo, but it did not compromise VZV's oncolytic potency. We further armed the VZV Ellen-ΔORF8 vector with a tet-off controlled mouse single-chain IL12 (scIL12) gene cassette. This augmented virus was validated for its oncolytic activity and triggered systemic antitumor immune responses in the immunocompetent B16-F10-nectin1 model.

CONCLUSIONS

These findings highlight the potential of using Ellen-ΔORF8-tet-off-scIL12 as a novel VZV-based oncolytic virotherapy.

Detection of varicella zoster virus DNA in blood from immunocompromised patients during the week preceding the onset of herpes zoster rash

OBJECTIVE

To assess whether varicella zoster virus (VZV) DNA can be detected in blood before herpes zoster (HZ) rash onset.

METHOD

Monocentric retrospective study from January 2019 to March 2023 including patients with HZ and stored blood samples performed during the week preceding the onset of HZ rash. Blood samples were retrospectively analyzed for VZV DNA by quantitative PCR.

RESULTS

Among the 138 patients with HZ during the study period, stored blood samples performed during the week preceding the onset of HZ rash were available for 13 of them. Twelve (92 %) patients were immunosuppressed, mostly due to solid organ transplantation (38 %), solid malignancy (31 %) or autoimmune disease (23 %). During the week preceding HZ onset, VZV DNA was detected in blood from 10 (77 %) patients, with a median value of 3.6 log (copies/mL) (IQR 3.3-3.9). At the time of HZ onset, all VZV PCR performed in available blood samples were positive.

CONCLUSION

Our findings demonstrates that VZV DNA can be commonly detected in blood from immunocompromised patients during the prodromal phase of HZ. Early screening of VZV DNA in blood from high-risk immunocompromised patients might improve HZ therapeutic management.

Reactivation of Herpes Zoster in a Young Patient With Multiple Sclerosis Under Dimethyl Fumarate Treatment and Normal Lymphocyte Subsets Count: A Case Report

Herpes zoster (HZ) infection results from the reactivation of the varicella-zoster virus (VZV), which remains dormant in the dorsal root ganglia after an initial chickenpox infection. Although HZ appears more common in people with multiple sclerosis (MS) than expected in the general population, few studies have investigated this association, particularly with a normal absolute lymphocyte count (ALC). Additionally, no reported cases have discussed the clinical presentation of such patients. This report describes the case of a 26-year-old female with a known history of relapsing-remitting MS on dimethyl fumarate (DMF) treatment. She presented with a history of painful erythematous blisters, diagnosed as acute HZ infection with a normal ALC. This case provides evidence that warrants further research and attention to the management of patients with MS receiving DMF, particularly regarding infectious risks. It highlights the importance of pharmacovigilance and the potential benefits of VZV and HZ immunization in DMF recipients.

Cell Intrinsic Determinants of Alpha Herpesvirus Latency and Pathogenesis in the Nervous System

Alpha herpesvirus infections (α-HVs) are widespread, affecting more than 70% of the adult human population. Typically, the infections start in the mucosal epithelia, from which the viral particles invade the axons of the peripheral nervous system. In the nuclei of the peripheral ganglia, α-HVs establish a lifelong latency and eventually undergo multiple reactivation cycles. Upon reactivation, viral progeny can move into the nerves, back out toward the periphery where they entered the organism, or they can move toward the central nervous system (CNS). This latency-reactivation cycle is remarkably well controlled by the intricate actions of the intrinsic and innate immune responses of the host, and finely counteracted by the viral proteins in an effort to co-exist in the population. If this yin-yang- or Nash-equilibrium-like balance state is broken due to immune suppression or genetic mutations in the host response factors particularly in the CNS, or the presence of other pathogenic stimuli, α-HV reactivations might lead to life-threatening pathologies. In this review, we will summarize the molecular virus-host interactions starting from mucosal epithelia infections leading to the establishment of latency in the PNS and to possible CNS invasion by α-HVs, highlighting the pathologies associated with uncontrolled virus replication in the NS.

Mutations in Coding and Non-Coding Regions in Varicella-Zoster Virus Causing Fatal Hemorrhagic Fever Without Rash in an Immunocompetent Patient: Case Report

INTRODUCTION

We report the case of a fatal hemorrhagic varicella primary infection in an immunocompetent man and whole-genome characterization of the virus for the investigation of biomarkers of virulence.

CASE

A 38-year-old patient born in Nigeria presented to the emergency department with abdominal pain and subsequently developed fatal hemorrhagic disease without skin rash. Extensive laboratory tests including serology and PCR for arenaviruses, bunyaviruses and ebolaviruses were negative. Varicella-zoster virus (VZV) PCR of sera, liver and spleen tissue samples from autopsy revealed the presence of VZV DNA. Primary infection by varicella-zoster virus with hemorrhagic manifestations was diagnosed after virological testing. The VZV genome was sequenced using a mWGS approach. Bioinformatic analysis showed 53 mutations across the genome, 33 of them producing non-synonymous variants affecting up to 14 genes. Some of them, such as ORF11 and ORF 62, encoded for essential functions related to skin or neurotropism. To our knowledge, the mutations reported here have never been described in a VZV causing such a devastating outcome.

DISCUSSION

In immunocompetent patients, viral factors should be considered in patients with uncommon symptoms or severe diseases. Some relevant mutations revealed by using whole genome sequencing (WGS) directly from clinical samples may be involved in this case and deserves further investigation.

CONCLUSION

Differential diagnosis of varicella-zoster virus in immunocompetent adults should be considered among patients with suspected VHF, even if the expected vesicular rash is not present at admission and does not arise thereafter. Whole genome sequencing of strains causing uncommon symptoms and/or mortality is needed for epidemiological surveillance and further characterization of putative markers of virulence. Additionally, this report highlights the recommendation for a VZV vaccination policy in non-immunized migrants from developing countries.

Vestibular Nucleus Involvement in Patients With Acute Vertigo Due to Herpes Zoster Oticus or Vestibular Neuritis

OBJECTIVES

Herpes zoster oticus (HZO) typically provokes vestibular symptoms and is traditionally viewed as a cranial nerve equivalent of shingles, but in contrast to vestibular neuritis (VN), it is unclear whether the pathology of HZO is limited to the vestibular nerve (neuritis) or can also involve the brainstem (nucleitis).

METHODS

We retrospectively compared brain MRIs of patients with HZO with those of patients with VN to study radiologic changes in the brainstem.

RESULTS

Five of 10 patients with HZO showed signal abnormalities in the vestibular nuclei, which lie in multiple vascular territories, whereas no patients with VN exhibited such findings.

DISCUSSION

HZO may at least in part reflect vestibular nucleitis, as opposed to a pure neuritis.

A Rare Case of Chickenpox Infection Complicated by Hip Septic Arthritis

Chickenpox represents a viral malady characterized by the emergence of vesicular skin eruptions. This ailment is frequently encountered during childhood and typically manifests a benign course devoid of complications. Among the prevalent complications, secondary bacterial skin infections ranging from superficial impetigo to subcutaneous abscesses are most frequently observed. Instances of musculoskeletal complications, such as septic arthritis and osteomyelitis, are rarely observed. In any patient presenting complaints of bone pain or arthralgia, either during varicella eruptions or during the healing process, it is imperative to maintain a vigilant consideration for the potential manifestation of septic arthritis and osteomyelitis. Timely diagnosis holds paramount importance, as the administration of appropriate antibiotics can effectively forestall the necessity for surgical interventions and mitigate the risk of sequela. In this context, we present a case wherein chickenpox resulted in the complication of right hip septic arthritis.

Imposter Zoster: An Atypical Case of Varicella-Zoster Virus Infection

In this report, we describe a case involving an 80-year-old female who presented to the emergency department with an acute onset of left upper quadrant abdominal pain. The chief complaint misled us down multiple pathways of considering ischemic bowel disease, peptic ulcer disease, and small bowel obstruction. As a result, this led to costly and invasive diagnostic studies. However, the actual cause eventually became apparent - a cutaneous varicella-zoster virus infection. This case underscores the significance of maintaining a comprehensive list of potential diagnoses, particularly in elderly adults who commonly present atypically and often face difficulty expressing their symptoms. It also underlines the diagnostic challenges associated with identifying shingles without cutaneous findings. Early detection is crucial in preventing unnecessary tests, minimizing costs, and avoiding treatment delays. Furthermore, the case is a powerful example of the importance of vaccination, which has been proven to be 68-97% effective in preventing shingles and postherpetic neuralgia, depending on the individual's immune function.

Overview of Diagnostic Methods, Disease Prevalence and Transmission of Mpox (Formerly Monkeypox) in Humans and Animal Reservoirs

Mpox-formerly monkeypox-is a re-emerging zoonotic virus disease, with large numbers of human cases reported during multi-country outbreaks in 2022. The close similarities in clinical symptoms that Mpox shares with many orthopoxvirus (OPXV) diseases make its diagnosis challenging, requiring laboratory testing for confirmation. This review focuses on the diagnostic methods used for Mpox detection in naturally infected humans and animal reservoirs, disease prevalence and transmission, clinical symptoms and signs, and currently known host ranges. Using specific search terms, up to 2 September 2022, we identified 104 relevant original research articles and case reports from NCBI-PubMed and Google Scholar databases for inclusion in the study. Our analyses observed that molecular identification techniques are overwhelmingly being used in current diagnoses, especially real-time PCR (3982/7059 cases; n = 41 studies) and conventional PCR (430/1830 cases; n = 30 studies) approaches being most-frequently-used to diagnose Mpox cases in humans. Additionally, detection of Mpox genomes, using qPCR and/or conventional PCR coupled to genome sequencing methods, offered both reliable detection and epidemiological analyses of evolving Mpox strains; identified the emergence and transmission of a novel clade 'hMPXV-1A' lineage B.1 during 2022 outbreaks globally. While a few current serologic assays, such as ELISA, reported on the detection of OPXV- and Mpox-specific IgG (891/2801 cases; n = 17 studies) and IgM antibodies (241/2688 cases; n = 11 studies), hemagglutination inhibition (HI) detected Mpox antibodies in human samples (88/430 cases; n = 6 studies), most other serologic and immunographic assays used were OPXV-specific. Interestingly, virus isolation (228/1259 cases; n = 24 studies), electron microscopy (216/1226 cases; n = 18 studies), and immunohistochemistry (28/40; n = 7 studies) remain useful methods of Mpox detection in humans in select instances using clinical and tissue samples. In animals, OPXV- and Mpox-DNA and antibodies were detected in various species of nonhuman primates, rodents, shrews, opossums, a dog, and a pig. With evolving transmission dynamics of Mpox, information on reliable and rapid detection methods and clinical symptoms of disease is critical for disease management.

REAC Antalgic Neuro Modulation in Chronic Post Herpetic Neuralgia

BACKGROUND

Chronic post-herpetic neuralgia (CPHN) is a symptomatic condition that afflicts adults and elderly individuals. The chronicity of this symptomatology can be conditioned by the epigenetic modifications induced by the virus on the processes of neurotransmission and sensitivity to pain. The aim of this study is to investigate whether manipulating endogenous bioelectrical activity (EBA), responsible for neurotransmission processes and contributing to the induction of epigenetic modifications, can alleviate pain symptoms.

METHODS

This manipulation was carried out with the antalgic neuromodulation (ANM) treatment of radioelectric asymmetric conveyer (REAC) technology. Pain assessment before and after treatment was performed using a numerical analog scale (NAS) and a simple descriptive scale (SDS).

RESULTS

The results of the analysis showed an over four-point decrease in NAS scale score and over one point decrease in SDS scale score, with a statistical significance for both tests of p < 0.005.

CONCLUSIONS

The results obtained in this study demonstrate how REAC ANM manipulation of EBA can lead to improvement in epigenetically conditioned symptoms such as CPHN. These results should prompt further research to expand knowledge and ensure optimized therapeutic outcomes.

Rodent models of postherpetic neuralgia: How far have we reached?

Background

Induced by varicella zoster virus (VZV), postherpetic neuralgia (PHN) is one of the common complications of herpes zoster (HZ) with refractory pain. Animal models play pivotal roles in disclosing the pain mechanisms and developing effective treatments. However, only a few rodent models focus on the VZV-associated pain and PHN.

Objective

To summarize the establishment and characteristics of popular PHN rodent models, thus offer bases for the selection and improvement of PHN models.

Design

In this review, we retrospect two promising PHN rodent models, VZV-induced PHN model and HSV1-induced PHN model in terms of pain-related evaluations, their contributions to PHN pathogenesis and pharmacology.

Results

Significant difference of two PHN models is the probability of virus proliferation; 2) Most commonly used pain evaluation of PHN model is mechanical allodynia, but pain-induced anxiety and other behaviours are worth noting; 3) From current PHN models, pain mechanisms involve changes in virus gene and host gene expression, neuroimmune-glia interactions and ion channels; 4) antiviral drugs and classical analgesics serve more on the acute stage of herpetic pain.

Conclusions

Different PHN models assessed by various pain evaluations combine to fulfil more comprehensive understanding of PHN.

Approaches for Selective Vaccinations in Cirrhotic Patients

Bacterial and viral infections are common in cirrhotic patients, and their occurrence is associated with the severity of liver disease. Bacterial infection may increase the probability of death by 3.75 times in patients with decompensated cirrhosis, with ranges of 30% at 1 month and 63% at 1 year after infection. We illustrate the indications and the modalities for vaccinating cirrhotic patients. This topic is important for general practitioners and specialists.

Varicella-zoster virus in actively spreading segmental vitiligo skin: Pathological, immunochemical, and ultrastructural findings (a first and preliminary study)

Segmental vitiligo (SV) is a unilateral subtype of vitiligo which is clinically characterized by a cutaneous depigmentation and histologically by a melanocyte loss from the epidermis and hair follicle reservoirs. To date, its pathogenesis remains a mystery. In many cases, this skin depigmentation shares several clinical features and dysfunctions with herpes zoster (HZ). So, for the first time, we examined whether any nucleus and cell fusion associated with a positive immunolabelling of varicella-zoster virus (VZV) and VZV mature virions could be found in SV skin samples as in herpes zoster (HZ). A total of 40 SV samples were used for histological and immunochemical studies. Control samples were obtained from three HZ, and 10 generalized vitiligo lesions. For ultrastructural study, three recent SV and one HZ as controls were recruited. Here, we report that nuclear fusion in epidermal cells were statistically associated with recent SV (p < .001), whereas syncytia formation was associated with long-lasting SV (p = .001). A positive detection of VZV antigen was statistically associated in the epidermis with recent SV and in the dermis with long-lasting SV (p = .001). Finally, the discovery of mature virions in 3/3 recent SV samples provides additional arguments for our viral hypothesis.

Family Herpesviridae and neuroinfections: current status and research in progress

This article addresses the relationship between human herpesviruses (HHVs) and neuroinfections. Alphaherpesviruses, betaherpesviruses and gammaherpesviruses are neurotropic viruses that establish latency and exhibit reactivation capacity. Encephalitis and meningitis are common in cases of HHV. The condition promoted by HHV infection is a purported trigger for certain neurodegenerative diseases. Ongoing studies have identified an association between HSV-1 and the occurrence of Alzheimer's disease, multiple sclerosis and infections by HHV-6 and Epstein-Barr virus. In this review, we highlight the importance of research investigating the role of herpesviruses in the pathogenesis of diseases that affect the nervous system and describe other studies in progress.

Viral meningitis in Sudanese children: Differentiation, etiology and review of literature

Diagnosis of viral meningitis (VM) is uncommon practice in Sudan and there is no local viral etiological map. We therefore intended to differentiate VM using standardized clinical codes and determine the involvement of herpes simplex virus types-1 and 2 (HSV-1/2), varicella zoster virus, non-polio human enteroviruses (HEVs), and human parechoviruses in meningeal infections in children in Sudan. This is a cross-sectional hospital-based study. Viral meningitis was differentiated in 503 suspected febrile attendee of Omdurman Hospital for Children following the criteria listed in the Clinical Case Definition for Aseptic/Viral Meningitis. Patients were children age 0 to 15 years. Viral nucleic acids (DNA/RNA) were extracted from cerebrospinal fluid (CSF) specimens using QIAamp® UltraSens Virus Technology. Complementary DNA was prepared from viral RNA using GoScriptTM Reverse Transcription System. Viral nucleic acids were amplified and detected using quantitative TaqMan® Real-Time and conventional polymerase chain reactions (PCRs). Hospital diagnosis of VM was assigned to 0%, when clinical codes were applied; we considered 3.2% as having VM among the total study population and as 40% among those with proven infectious meningitis. Two (0.4%) out of total 503 CSF specimens were positive for HSV-1; Ct values were 37.05 and 39.10 and virus copies were 652/PCR run (261 × 103/mL CSF) and 123/PCR run (49.3 × 103/mL CSF), respectively. Other 2 (0.4%) CSF specimens were positive for non-polio HEVs; Ct values were 37.70 and 38.30, and the approximate virus copies were 5E2/PCR run (~2E5/mL CSF) and 2E2/PCR run (~8E4/mL CSF), respectively. No genetic materials were detected for HSV-2, varicella zoster virus, and human parechoviruses. The diagnosis of VM was never assigned by the hospital despite fulfilling the clinical case definition. Virus detection rate was 10% among cases with proven infectious meningitis. Detected viruses were HSV-1 and non-polio HEVs. Positive virus PCRs in CSFs with normal cellular counts were seen.

SARS-CoV-2 infection and lytic reactivation of herpesviruses: A potential threat in the postpandemic era?

The outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is the causative pathogen for the coronavirus disease 2019 (COVID-19) pandemic, has greatly stressed our healthcare system. In addition to severe respiratory and systematic symptoms, several comorbidities increase the risk of fatal disease outcomes, including chronic viral infections. Increasing cases of lytic reactivation of human herpesviruses in COVID-19 patients and vaccinated people have been reported recently. SARS-CoV2 coinfection, COVID-19 treatments, and vaccination may aggravate those herpesvirus-associated diseases by reactivating the viruses in latently infected host cells. In this review, we summarize recent clinical findings and limited mechanistic studies regarding the relationship between SARS-CoV-2 and different human herpesviruses that suggest an ongoing potential threat to human health in the postpandemic era.

Relative efficacy of varicella vaccines: network meta-analysis of randomized controlled trials

OBJECTIVE

Although varicella vaccination is highly effective, no head-to-head randomized controlled trials (RCTs) have compared the efficacy of different vaccine formulations. This study assessed the relative efficacy of different varicella vaccines using network meta-analysis (NMA).

METHODS

We estimated the relative efficacies of varicella vaccines and dosing regimens from RCTs using Bayesian NMA. Modeling-based time-series NMA (MBNMA) was performed, accounting for differences in time since vaccination, to extrapolate long-term vaccine efficacy (VE).

RESULTS

Eight RCTs were included based on systematic review of biomedical databases. Efficacy data were reported for four varicella-containing vaccines: Varivax (V-MSD, one and two dose), Varilrix (V-GSK, one dose), Priorix-Tetra (MMRV-GSK, one dose), and Sinovac (V-Sinovac, one dose). All varicella vaccines were effective versus no vaccination. Two-dose V-MSD (98.29%, 95% credible interval [CrI] 96.08-99.23) showed significantly higher VE versus all one-dose varicella-containing vaccines, but no significant difference versus two-dose MMRV-GSK (95.19%, 95% CrI 90.3-97.63). Two-dose MMRV-GSK showed higher VE than one-dose V-GSK (66.47%; 95% CrI 43.02-79.43), but no significant differences in VE versus one-dose V-MSD or one-dose V-Sinovac. In one-dose comparisons, V-MSD showed significantly higher VE (93.09%, 95% CrI 89.13-95.96) than V-GSK, but no significant difference versus V-Sinovac (89.22%; 95% CrI 67.1-96.5). MBNMA indicated that protection against varicella was sustained without waning over the 10 year follow-up.

CONCLUSIONS

Our study reported higher VE for two-dose V-MSD and MMRV-GSK. Among one-dose formulations, one-dose V-MSD was more efficacious than one-dose V-GSK. Policymakers should take into consideration differences in VE when implementing one- versus two-dose strategies in universal vaccination programs.

Role of Epitranscriptomic and Epigenetic Modifications during the Lytic and Latent Phases of Herpesvirus Infections

Herpesviruses are double-stranded DNA viruses occurring at a high prevalence in the human population and are responsible for a wide array of clinical manifestations and diseases, from mild to severe. These viruses are classified in three subfamilies (Alpha-, Beta- and Gammaherpesvirinae), with eight members currently known to infect humans. Importantly, all herpesviruses can establish lifelong latent infections with symptomatic or asymptomatic lytic reactivations. Accumulating evidence suggest that chemical modifications of viral RNA and DNA during the lytic and latent phases of the infections caused by these viruses, are likely to play relevant roles in key aspects of the life cycle of these viruses by modulating and regulating their replication, establishment of latency and evasion of the host antiviral response. Here, we review and discuss current evidence regarding epitranscriptomic and epigenetic modifications of herpesviruses and how these can influence their life cycles. While epitranscriptomic modifications such as m⁶A are the most studied to date and relate to positive effects over the replication of herpesviruses, epigenetic modifications of the viral genome are generally associated with defense mechanisms of the host cells to suppress viral gene transcription. However, herpesviruses can modulate these modifications to their own benefit to persist in the host, undergo latency and sporadically reactivate.

A Review with Updated Perspectives on the Antiviral Potentials of Traditional Medicinal Plants and Their Prospects in Antiviral Therapy

Exploration of the traditional medicinal plants is essential for drug discovery and development for various pharmacological targets. Various phytochemicals derived from medicinal plants were extensively studied for antiviral activity. This review aims to highlight the role of medicinal plants against viral infections that remains to be the leading cause of human death globally. Antiviral properties of phytoconstituents isolated from 45 plants were discussed for five different types of viral infections. The ability of the plants’ active compounds with antiviral effects was highlighted as well as their mechanism of action, pharmacological studies, and toxicological data on a variety of cell lines. The experimental values, such as IC₅₀, EC₅₀, CC₅₀, ED₅₀, TD₅₀, MIC₁₀₀, and SI of the active compounds, were compiled and discussed to determine their potential. Among the plants mentioned, 11 plants showed the most promising medicinal plants against viral infections. Sambucus nigra and Clinacanthus nutans manifested antiviral activity against three different types of viral infections. Echinacea purpurea, Echinacea augustofolia, Echinacea pallida, Plantago major, Glycyrrhiza uralensis, Phyllanthus emblica, Camellia sinensis, and Cistus incanus exhibited antiviral activity against two different types of viral infections. Interestingly, Nicotiana benthamiana showed antiviral effects against mosquito-borne infections. The importance of phenolic acids, alkamides, alkylamides, glycyrrhizin, epicatechin gallate (ECG), epigallocatechin gallate (EGCG), epigallocatechin (EGC), protein-based plant-produced ZIKV Envelope (PzE), and anti-CHIKV monoclonal antibody was also reviewed. An exploratory approach to the published literature was conducted using a variety of books and online databases, including Scopus, Google Scholar, ScienceDirect, Web of Science, and PubMed Central, with the goal of obtaining, compiling, and reconstructing information on a variety of fundamental aspects, especially regarding medicinal plants. This evaluation gathered important information from all available library databases and Internet searches from 1992 to 2022.

Varicella Zoster Virus Reactivation Involving the Vagus Nerve

OBJECTIVES

To characterize the presentation, clinical course and functional outcomes of patients with varicella zoster virus (VZV) reactivation involving the vagus nerve. To highlight the role of otolaryngology in acute and long-term management of laryngopharyngeal VZV and its sequelae.

METHODS

Retrospective review of 3 patients with laryngopharyngeal VZV, managed at a tertiary referral center.

RESULTS

All cases presented with vesicular lesions involving mucosa of the laryngopharynx. Each experienced vocal fold hypomobility, among other otolaryngologic sequelae. All were treated with systemic antivirals and corticosteroids. Mucosal lesions resolved within 7 days of treatment initiation; functional deficits persisted for months to years. Dysphonia improved to a plateau at 3 months, while dysphagia took longer to resolve. One patient with disseminated disease experienced bilateral vocal fold paralysis requiring temporary tracheostomy.

CONCLUSIONS

Vagal neuropathy secondary to VZV reactivation is a rare clinical entity with a variety of laryngeal manifestations. Early initiation of systemic therapy and serial endoscopic evaluations are critical components of acute management when laryngopharyngeal involvement is suspected. Otolaryngologists should plan for long-term phonatory and deglutitive therapy in these cases, as neurologic sequelae can persist for months to years following initial insult.

LEVEL OF EVIDENCE

Level 4 (Case-series).

Programmed Cell Death-Dependent Host Defense in Ocular Herpes Simplex Virus Infection

Herpes simplex virus type 1 (HSV1) remains one of the most ubiquitous human pathogens on earth. The classical presentation of HSV1 infection occurs as a recurrent lesions of the oral mucosa commonly refer to as the common cold sore. However, HSV1 also is responsible for a range of ocular diseases in immunocompetent persons that are of medical importance, causing vision loss that may result in blindness. These include a recurrent corneal disease, herpes stromal keratitis, and a retinal disease, acute retinal necrosis, for which clinically relevant animal models exist. Diverse host immune mechanisms mediate control over herpesviruses, sustaining lifelong latency in neurons. Programmed cell death (PCD) pathways including apoptosis, necroptosis, and pyroptosis serve as an innate immune mechanism that eliminates virus-infected cells and regulates infection-associated inflammation during virus invasion. These different types of cell death operate under distinct regulatory mechanisms but all server to curtail virus infection. Herpesviruses, including HSV1, have evolved numerous cell death evasion strategies that restrict the hosts ability to control PCD to subvert clearance of infection and modulate inflammation. In this review, we discuss the key studies that have contributed to our current knowledge of cell death pathways manipulated by HSV1 and relate the contributions of cell death to infection and potential ocular disease outcomes.

Health technology assessment of varicella vaccine in the Armed Forces

Background

The Indian Armed Forces, on entry, vaccinates all cadets and recruits with varicella vaccine for the prevention of varicella. This health technology assessment (HTA) report puts forth evidence for HTA of varicella vaccination in the Armed Forces in various domains namely clinical, societal, ethical, economic, and legal.

Methods

The policy question under each domain has been developed according to best-practice methods for HTA. The costs included were hospitalization cost due to varicella infection; training lost cost; the varicella vaccine cost; cost of the side effects of vaccine; and the outbreak investigation cost. The incremental cost-effectiveness ratio (ICER) for varicella cases averted and man-days saved, and quality-adjusted life years (QALYs) gained due to varicella vaccination strategy were calculated.

Results

Evidence suggests a reduction of 81% in hospitalization rates with 19392 man-days saved per 1 lakh population due to varicella vaccination strategy. The ICER for varicella cases averted is estimated to be Rs 56732/- per case averted and Rs 5687/- per man-day saved. QALYs gained due to two-dose varicella vaccination strategy is estimated to be 1152 per 1 lakh population with cost per QALY gained Rs 95735/-.

Conclusion

The study showed a large reduction in hospitalizations and consequently man-days lost after the introduction of the vaccination strategy. The QALYs was another aspect of importance brought out by this study. Thus, a two-dose vaccination strategy for varicella-zoster virus (VZV) for the Armed Forces trainees is a cost-effective policy.