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

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.

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.

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.

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.

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.

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.

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.

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.

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.

Review on inactivation of airborne viruses using non-thermal plasma technologies: from MS2 to coronavirus

Although several non-thermal plasmas (NTPs) technologies have been widely investigated in air treatment, very few studies have focused on the inactivation mechanism of viruses by NTPs. Due to its efficiency and environmental compatibility, non-thermal plasma could be considered a promising virus-inactivation technology. Plasma is a partly or fully ionized gas including some species (i.e., electrons, free radicals, ions, and neutral molecules) to oxidize pollutants or inactivate harmful organisms. Non-thermal plasmas are made using less energy and have an active electron at a much higher temperature than bulk gas molecules. This review describes NTPs for virus inactivation in indoor air. The different application processes of plasma for microorganism inactivation at both laboratory and pilot-scale was also reviewed This paper reports on recent advances in this exciting area of viral inactivation identifying applications and mechanisms of inactivation, and summarizing the results of the latest experiments in the literature. Moreover, special attention was paid to the mechanism of virus inactivation. Finally, the paper suggests research directions in the field of airborne virus inactivation using non-thermal plasma.

Seroprevalence of Varicella in Pregnant Women and Newborns in a Region of Colombia

We estimate the seroprevalence of IgG antibodies to varicella zoster virus (VZV) based on the first serological study in a cohort of pregnant women and newborns from the Aburrá Valley (Antioquia-Colombia) who attended delivery in eight randomly chosen hospitals. An indirect enzyme immunoassay was used to determine anti-VZV IgG antibodies. Generalized linear models were constructed to identify variables that modify seropositivity. In pregnant women, seropositivity was 85.8% (95% CI: 83.4-85.9), seronegativity was 12.6% (95% CI: 10.8-14.6), and concordance with umbilical cord titers was 90.0% (95% CI: 89-91). The seropositivity of pregnant women was lower in those who lived in rural areas (IRR: 0.4, 95% CI: 0.2-0.7), belonged to the high socioeconomic status (IRR: 0.4, 95% CI: 0.2-0.7), and had studied 11 years or more (IRR: 0.6, 95% CI: 0.4-0.8). Among newborns, seropositivity was lower in those who weighed less than 3000 g (IRR: 0.8, 95% CI: 0.6-1.0). The high seropositivity and seronegativity pattern indicates the urgent need to design preconception consultation and vaccination reinforcement for women of childbearing age according to their sociodemographic conditions, to prevent infection and complications in the mother and newborn.

Investigation of Cyprinid Herpesvirus 3 (CyHV-3) Disease Periods and Factors Influencing CyHV-3 Transmission in A Low Stocking Density Infection Trial

Simple Summary

Pathogens are the primary limitation to aquaculture production of fish and a major issue in consideration of the interface between cultured and wild populations of fishes worldwide. While rapid spread of fish pathogens between populations (wild or farmed) is generally anthropogenic and the result of trade, the mechanisms of transmission once a pathogen has been introduced to a fish population are not well understood. The most widespread pathogen impacting both aquaculture and wild populations of common carp (Cyprinus carpio, carp) is Cyprinid herpesvirus 3 (CyHV-3). To understand how CyHV-3 is transmitted in a population we conducted a series of infection trials, designed to determine the kinetics CyHV-3 infections, identify the contributions of direct and indirect forms of CyHV-3 transmission, and to determine the contributions of contact rate, viral load, pathogenicity, and contact type. We found that direct contact between fish was the primary mechanism of CyHV-3 transmission rather than transmission through contaminated water. Additionally, CyHV-3 transmission occurred primarily during the incubation period of CyHV-3, prior to the appearance of disease signs and disease-associated reduction in contact rate.

Abstract

Cyprinid herpesvirus 3 (CyHV-3) is the etiological agent of koi herpesvirus disease (KHVD) and important pathogen of aquaculture and wild populations of common carp worldwide. Understanding the relative contributions of direct and indirect transmission of CyHV-3 as well as the factors that drive CyHV-3 transmission can clarify the importance of environmental disease vectors and is valuable for informing disease modeling efforts. To study the mechanisms and factors driving CyHV-3 transmission we conducted infection trials that determined the kinetics of KHVD and the contributions of direct and indirect forms of CyHV-3 transmission, as well as the contributions of contact rate, viral load, pathogenicity and contact type. The incubation period of KHVD was 5.88 + 1.75 days and the symptomatic period was 5.31 + 0.87 days. Direct transmission was determined to be the primary mechanism of CyHV-3 transmission (OR = 25.08, 95%CI = 10.73–99.99, p = 4.29 × 10⁻¹⁸) and transmission primarily occurred during the incubation period of KHVD. Direct transmission decreased in the symptomatic period of disease. Transmissibility of CyHV-3 and indirect transmission increased during the symptomatic period of disease, correlating with increased viral loads. Additionally, potential virulence-transmission tradeoffs and disease avoidance behaviors relevant to CyHV-3 transmission were identified.

Atypical Presentation of Aseptic Meningitis Due to Varicella Zoster: A Case Report

Introduction

Varicella zoster virus (VZV) meningitis is primarily an infection of the immuno-compromised. However, it can also affect immunocompetent individuals. Reactivation of VZV typically presents with a distinct dermatomal rash suggestive of varicella zoster, but there have also been reports of VZV meningitis presenting without a rash.

Case Report

We describe a case of VZV meningitis in a healthy, 30-year-old male presenting to the emergency department shortly after receiving his first coronavirus disease 2019 vaccination. He was treated with intravenous acyclovir and then discharged home on oral valacyclovir.

Conclusion

Emergency physicians should consider aseptic meningitis in immunocompetent patients presenting with atypical headaches in this population.

Factors influencing series completion rates of recombinant herpes zoster vaccine in the United States: A retrospective pharmacy and medical claims analysis

BACKGROUND/OBJECTIVES

Vaccination against herpes zoster (HZ) is an effective strategy in protecting the population against consequences of varicella zoster virus reactivation. Optimal immunogenicity with recombinant zoster vaccine (RZV) relies on completion of the 2-dose series within 2-6 months from the first dose. The objectives of this study were to estimate RZV completion rates and adherence with the recommended administration schedule in the general United States population aged at least 50 years and to evaluate factors influencing completion rates.

METHODS

Longitudinal, open-source pharmacy and medical claims databases were analyzed for adults aged at least 50 years with a first RZV prescription filled between October 2017 and September 2019. The data were linked to Experian Marketing Services Consumer View data to obtain information regarding race. Completion rates and adherence were calculated overall and stratified according to claim source, age class, sex, and payer type. Logistic regression models were built for each subpopulation of interest to identify factors correlating with completion rates.

RESULTS

Overall, cumulative completion rates were 70.41% and 81.80% at 6 and 12 months, respectively. Median time to second dose was approximately 4 months (4.08-5.13 months) and adherence 67.62%. Completion rates were lower in the medical claims database compared with the pharmacy claims database (48.98% vs. 73.23% at 6 months). Regression models confirmed that pharmacy claim was an independent factor for higher completion rates, while African American race and Medicaid status were associated with lower completion rates. Most comorbidities, including chronic obstructive pulmonary disease and type 2 diabetes mellitus, were associated with lower completion rates.

CONCLUSION

Pharmacists contribute substantially to the overall high RZV completion rates in the United States. However, completion rates can be improved, especially in people receiving their first RZV dose at a physician's office. Future strategies should aim at lowering barriers to completing vaccination series in African Americans, Medicaid beneficiaries, and people with comorbidities.

The Ends Dictate the Means: Promoter Switching in Herpesvirus Gene Expression

Herpesvirus gene expression is dynamic and complex, with distinct complements of viral genes expressed at specific times in different infection contexts. These complex patterns of viral gene expression arise in part from the integration of multiple cellular and viral signals that affect the transcription of viral genes. The use of alternative promoters provides an increased level of control, allowing different promoters to direct the transcription of the same gene in response to distinct temporal and contextual cues. While once considered rare, herpesvirus alternative promoter usage was recently found to be far more pervasive and impactful than previously thought. Here we review several examples of promoter switching in herpesviruses and discuss the functional consequences on the transcriptional and post-transcriptional regulation of viral gene expression.

Intratracheal inoculation of human varicella zoster virus (VZV; MAV strain) vaccine successfully induced VZV IgG antibodies in rhesus monkeys

BACKGROUND

The objective of this study was to investigate whether the use of live attenuated varicella zoster virus (VZV) MAV vaccination can efficiently induce VZV antibody production in naive rhesus monkeys as an approach to prevent simian varicella virus (SVV) reactivation in animals immunosuppressed for transplantation studies.

RESULTS

Clinically available human VZV vaccine was used to induce the production of anti-VZV antibodies in rhesus monkeys. A vial of the vaccine was subcutaneously injected at 0 week, and the second and third vaccination was performed at 5 and 6 weeks by intratracheal inoculation. The titer of anti-VZV IgG was assessed at 0, 2, 4, 6, and 7 weeks. At 2 weeks, 3/16 were seropositive for VZV IgG. At 6 weeks, 9/16 were shown to be seropositive. At 7 weeks, 16/16 were found to be seropositive.

CONCLUSIONS

The VZV vaccine via intratrachael inoculation was shown to induce VZV IgG humoral immunity in rhesus monkeys and may be important immunosuppressed macaques for transplantation studies. Although the humoral immunity produced is an important finding, further studies will be necessary to confirm possible protection and it could protect probably against SVV infection in rhesus monkey.

Measuring association among censored antibody titer data

Censoring due to a limit of detection or limit of quantification happens quite often in many medical studies. Conventional approaches to deal with censoring when analyzing these data include, for example, the substitution method and the complete case (CC) analysis. More recently, maximum likelihood estimation (MLE) has been increasingly used. While the CC analysis and the substitution method usually lead to biased estimates, the MLE approach appears to perform well in many situations. This article proposes an MLE approach to estimate the association between two measurements in the presence of censoring in one or both quantities. The central idea is to use a copula function to join the marginal distributions of the two measurements. In various simulation studies, we show that our approach outperforms existing conventional methods (CC and substitution analyses). In addition, rank‐based measures of global association such as Kendall's tau or Spearman's rho can be studied, hence, attention is not only confined to Pearson's product‐moment correlation coefficient capturing solely linear association. We have shown in our simulations that our approach is robust to misspecification of the copula function or marginal distributions given a small association. Furthermore, we propose a straightforward MLE method to fit a (multiple) linear regression model in the presence of censoring in a covariate or both the covariate and the response. Given the marginal distribution of the censored covariate, our method outperforms conventional approaches. We also compare and discuss the performance of our method with multiple imputation and missing indicator model approaches.

Early examination of real-world uptake and second-dose completion of recombinant zoster vaccine in the United States from October 2017 to September 2019

Shingrix (Recombinant zoster vaccine, RZV) was approved in October 2017 in the United States (US) for the prevention of herpes zoster in adults aged 50 years and older. The vaccine is administered in two doses, with the second dose administration recommended between two and six months after the first dose. Examination of uptake and series completion is important to ensure appropriate use, especially at the time of vaccine introduction. This report provides demographic characteristics of patients receiving RZV between October 2017 and September 2019, first- and second-dose uptake, and a cumulative estimation of second-dose completion by month for US adults aged 50 years and older. Monthly uptake increased rapidly since October 2017; overall, 7,097,441 first doses of RZV were administered along with 4,277,636 second doses during the observed timeframe. Among people with an observed first-dose administration, 70% and 80% completed the two-dose series within six and 12 months post initial dose, respectively. This evidence suggests that RZV has rapidly been adopted by a large population in the US and most are following manufacturer or policy recommendations regarding series completion. Further analyses are needed to explore potential patient, provider, and policy-relevant characteristics associated with second-dose completion that could serve as targets for further improvement.

Advances and Perspectives in the Management of Varicella-Zoster Virus Infections

Varicella-zoster virus (VZV), a common and ubiquitous human-restricted pathogen, causes a primary infection (varicella or chickenpox) followed by establishment of latency in sensory ganglia. The virus can reactivate, causing herpes zoster (HZ, shingles) and leading to significant morbidity but rarely mortality, although in immunocompromised hosts, VZV can cause severe disseminated and occasionally fatal disease. We discuss VZV diseases and the decrease in their incidence due to the introduction of live-attenuated vaccines to prevent varicella or HZ. We also focus on acyclovir, valacyclovir, and famciclovir (FDA approved drugs to treat VZV infections), brivudine (used in some European countries) and amenamevir (a helicase-primase inhibitor, approved in Japan) that augur the beginning of a new era of anti-VZV therapy. Valnivudine hydrochloride (FV-100) and valomaciclovir stearate (in advanced stage of development) and several new molecules potentially good as anti-VZV candidates described during the last year are examined. We reflect on the role of antiviral agents in the treatment of VZV-associated diseases, as a large percentage of the at-risk population is not immunized, and on the limitations of currently FDA-approved anti-VZV drugs. Their low efficacy in controlling HZ pain and post-herpetic neuralgia development, and the need of multiple dosing regimens requiring daily dose adaptation for patients with renal failure urges the development of novel anti-VZV drugs.

Mastoid effusion on temporal bone MRI in patients with Bell's palsy and Ramsay Hunt syndrome

This study aimed to investigate the incidence of mastoid effusion on temporal bone magnetic resonance imaging (MRI) in patients with Bell’s palsy (BP) and Ramsay Hunt syndrome (RHS), and evaluate the usefulness of mastoid effusion in early differential diagnosis between BP and RHS. The incidence of mastoid effusion on 3.0 T—temporal bone MRI, which was conducted within 10 days after the onset of acute facial nerve palsy, was compared between 131 patients with BP and 33 patients with RHS. Findings of mastoid cavity on temporal bone MRI were classified into three groups as normal mastoid, mastoid effusion, and sclerotic change, and the incidence of ipsilesional mastoid effusion was significantly higher in RHS than BP (P < 0.001). Tympanic membrane was normal in 7 of 14 RHS patients with mastoid effusion, and injected without middle ear effusion in 7 patients. This study highlights significantly higher incidence of ipsilesional mastoid effusion in RHS than BP, and suggests that the presence of mastoid effusion may provide additional information for differential diagnosis between RHS and BP.

Herpes zoster of orofacial region

Herpes zoster (HZ) is a viral disease which is primarily caused by the nerve tissue, but its treatment necessitates a multidisciplinary approach. Varicella zoster virus (VZV) is a DNA virus that causes both primary and recurrent infection. HZ, also known as shingles, is a unique condition induced by VZV reactivation. Neuropathic pain, headache, malaise and sleep disruption are all prodromal symptoms in such cases. HZ generates a pruritic, localized and vesicular rash that is usually unilateral. Individuals who are immunocompromised as a result of disease or receiving any treatment are also at increased risk, regardless of their age. HZ and its sequelae set a major strain on patient's caregivers, health-care system and business. Despite recent advances, prevention and treatment of HZ, consequences remain a therapeutic challenge. This is a case report of HZ infection in a 56-year-old female patient who was managed with comprehensive medical treatment.

Zoster meningitis in an immunocompetent host with headache and atypical rash

Headache is a frequent emergency department (ED) complaint. Secondary headache, due to infectious causes, must be carefully evaluated as a differential diagnosis. Red flag signs and classic physical examination findings are available to aid the diagnosis and evaluation of secondary headache. These findings, however, are limited by poor sensitivity and predictive value. We present a case of Herpes zoster (HZ) meningitis in a young healthy male adult with major presenting symptom of headache and new-onset rash to underscore the variation in atypical presentations of aseptic meningitis. HZ-associated aseptic meningitis often presents with characteristic, but at times atypical rash. We recommend skin lesions be thoroughly evaluated, along with classic signs of fever and nuchal rigidity, to assist in the diagnosis of meningitis.

Toll-like receptor-mediated innate immunity against herpesviridae infection: a current perspective on viral infection signaling pathways

Background

In the past decades, researchers have demonstrated the critical role of Toll-like receptors (TLRs) in the innate immune system. They recognize viral components and trigger immune signal cascades to subsequently promote the activation of the immune system.

Main body

Herpesviridae family members trigger TLRs to elicit cytokines in the process of infection to activate antiviral innate immune responses in host cells. This review aims to clarify the role of TLRs in the innate immunity defense against herpesviridae, and systematically describes the processes of TLR actions and herpesviridae recognition as well as the signal transduction pathways involved.

Conclusions

Future studies of the interactions between TLRs and herpesviridae infections, especially the subsequent signaling pathways, will not only contribute to the planning of effective antiviral therapies but also provide new molecular targets for the development of antiviral drugs.