Varicella-zoster virus-related neurological complications: From infection to immunomodulatory therapies.

The Varicella-zoster virus (VZV), classified as a neurotropic member of the Herpesviridae family, exhibits a characteristic pathogenicity, predominantly inducing varicella, commonly known as chickenpox, during the initial infectious phase, and triggering the reactivation of herpes zoster, more commonly recognized as shingles, following its emergence from a latent state. The pathogenesis of VZV-associated neuroinflammation involves a complex interplay between viral replication within sensory ganglia and immune-mediated responses that contribute to tissue damage and dysfunction. Upon primary infection, VZV gains access to sensory ganglia, establishing latent infection within neurons. During reactivation, the virus can spread along sensory nerves, triggering a cascade of inflammatory mediators, chemokines, and immune cell infiltration in the affected neural tissues. The role of both adaptive and innate immune reactions, including the contributions of T and B cells, macrophages, and dendritic cells, in orchestrating the immune-mediated damage in the central nervous system is elucidated. Furthermore, the aberrant activation of the natural defence mechanism, characterised by the dysregulated production of immunomodulatory proteins and chemokines, has been implicated in the pathogenesis of VZV-induced neurological disorders, such as encephalitis, myelitis, and vasculopathy. The intricate balance between protective and detrimental immune responses in the context of VZV infection emphasises the necessity for an exhaustive comprehension of the immunopathogenic mechanisms propelling neuroinflammatory processes. Despite the availability of vaccines and antiviral therapies, VZV-related neurological complications remain a significant concern, particularly in immunocompromised individuals and the elderly. Elucidating these mechanisms might facilitate the emergence of innovative immunomodulatory strategies and targeted therapies aimed at mitigating VZV-induced neuroinflammatory damage and improving clinical outcomes. This comprehensive understanding enhances our grasp of viral pathogenesis and holds promise for pioneering therapeutic strategies designed to mitigate the neurological ramifications of VZV infections.

Alzheimer's disease and herpes viruses: Current events and perspectives.

Alzheimer's disease (AD) is a real and current scientific and societal challenge. Alzheimer's disease is characterised by a neurodegenerative neuroinflammatory process, but the etiopathogenetic mechanisms are still unclear. The possible infectious aetiology and potential involvement of Herpes viruses as triggers for the formation of extracellular deposits of amyloid beta (Aß) peptide (amyloid plaques) and intraneuronal aggregates of hyperphosphorylated and misfold could be a possible explanation. In fact, the possible genetic interference of Herpes viruses with the genome of the host neuronal cell or the stimulation of the infection to a continuous immune response with a consequent chronic inflammation could constitute those mechanisms underlying the development of AD, with possible implications in the understanding and management of the disease. Herpes viruses could be significantly involved in the pathogenesis of AD and in particular, their ability to reactivate in particular conditions such as immunocompromise and immunosenescence, could explain the neurological damage characteristic of AD. Our review aims to evaluate the state of the art of knowledge and perspectives regarding the potential relationship between Herpes viruses and AD, in order to be able to identify the possible etiopathogenetic mechanisms and the possible therapeutic implications.

Viral infections and pathogenesis of glaucoma: a comprehensive review.

Glaucoma is a leading cause of irreversible blindness worldwide, caused by the gradual degeneration of retinal ganglion cells and their axons. While glaucoma is primarily considered a genetic and age-related disease, some inflammatory conditions, such as uveitis and viral-induced anterior segment inflammation, cause secondary or uveitic glaucoma. Viruses are predominant ocular pathogens and can impose both acute and chronic pathological insults to the human eye. Many viruses, including herpes simplex virus, varicella-zoster virus, cytomegalovirus, rubella virus, dengue virus, chikungunya virus, Ebola virus, and, more recently, Zika virus (ZIKV) and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), have been associated with sequela of either primary or secondary glaucoma. Epidemiological and clinical studies suggest the association between these viruses and subsequent glaucoma development. Despite this, the ocular manifestation and sequela of viral infections are not well understood. In fact, the association of viruses with glaucoma is considered relatively uncommon in part due to underreporting and/or lack of long-term follow-up studies. In recent years, literature on the pathological spectrum of emerging viral infections, such as ZIKV and SARS-CoV-2, has strengthened this proposition and renewed research activity in this area. Clinical studies from endemic regions as well as laboratory and preclinical investigations demonstrate a strong link between an infectious trigger and development of glaucomatous pathology. In this article, we review the current understanding of the field with a particular focus on viruses and their association with the pathogenesis of glaucoma.

HerpesDRG: a comprehensive resource for human herpesvirus antiviral drug resistance genotyping.

The prevention and treatment of many herpesvirus associated diseases is based on the utilization of antiviral therapies, however therapeutic success is limited by the development of drug resistance. Currently no single database cataloguing resistance mutations exists, which hampers the use of sequence data for patient management. We therefore developed HerpesDRG, a drug resistance mutation database that incorporates all the known resistance genes and current treatment options, built from a systematic review of available genotype to phenotype literature. The database is released along with an R package that provides a simple approach to resistance variant annotation and clinical implication analysis from common sanger and next generation sequencing data. This represents the first openly available and community maintainable database of drug resistance mutations for the human herpesviruses (HHV), developed for the community of researchers and clinicians tackling HHV drug resistance.

Translational arrest and mRNA decay are independent activities of alphaherpesvirus virion host shutoff proteins.

The herpes simplex virus 1 (HSV1) virion host shutoff (vhs) protein is an endoribonuclease that regulates the translational environment of the infected cell, by inducing the degradation of host mRNA via cellular exonuclease activity. To further understand the relationship between translational shutoff and mRNA decay, we have used ectopic expression to compare HSV1 vhs (vhsH) to its homologues from four other alphaherpesviruses - varicella zoster virus (vhsV), bovine herpesvirus 1 (vhsB), equine herpesvirus 1 (vhsE) and Marek's disease virus (vhsM). Only vhsH, vhsB and vhsE induced degradation of a reporter luciferase mRNA, with poly(A)+ in situ hybridization indicating a global depletion of cytoplasmic poly(A)+ RNA and a concomitant increase in nuclear poly(A)+ RNA and the polyA tail binding protein PABPC1 in cells expressing these variants. By contrast, vhsV and vhsM failed to induce reporter mRNA decay and poly(A)+ depletion, but rather, induced cytoplasmic G3BP1 and poly(A)+ mRNA- containing granules and phosphorylation of the stress response proteins eIF2α and protein kinase R. Intriguingly, regardless of their apparent endoribonuclease activity, all vhs homologues induced an equivalent general blockade to translation as measured by single-cell puromycin incorporation. Taken together, these data suggest that the activities of translational arrest and mRNA decay induced by vhs are separable and we propose that they represent sequential steps of the vhs host interaction pathway.

Impaired STING Activation Due to a Variant in the E3 Ubiquitin Ligase AMFR in a Patient with Severe VZV Infection and Hemophagocytic Lymphohistiocytosis.

Varicella zoster virus (VZV) is a neurotropic alphaherpesvirus exclusively infecting humans, causing two distinct pathologies: varicella (chickenpox) upon primary infection and herpes zoster (shingles) following reactivation. In susceptible individuals, VZV can give rise to more severe clinical manifestations, including disseminated infection, pneumonitis, encephalitis, and vasculopathy with stroke. Here, we describe a 3-year-old boy in whom varicella followed a complicated course with thrombocytopenia, hemorrhagic and necrotic lesions, pneumonitis, and intermittent encephalopathy. Hemophagocytic lymphohistiocytosis (HLH) was strongly suspected and as the condition deteriorated, HLH therapy was initiated. Although the clinical condition improved, longstanding hemophagocytosis followed despite therapy. We found that the patient carries a rare monoallelic variant in autocrine motility factor receptor (AMFR), encoding a ubiquitin ligase involved in innate cytosolic DNA sensing and interferon (IFN) production through the cyclic GMP-AMP synthase-stimulator of IFN genes (cGAS-STING) pathway. Peripheral blood mononuclear cells (PBMCs) from the patient exhibited impaired signaling downstream of STING in response dsDNA and 2'3'-cGAMP, agonists of cGAS and STING, respectively, and fibroblasts from the patient showed impaired type I IFN responses and significantly increased VZV replication. Overexpression of the variant AMFR R594C resulted in decreased K27-linked STING ubiquitination compared to WT AMFR. Moreover, ImageStream technology revealed reduced STING trafficking from ER to Golgi in cells expressing the patient AMFR R594C variant. This was supported by a dose-dependent dominant negative effect of expression of the patient AMFR variant as measured by IFN-ß reporter gene assay. Finally, lentiviral transduction with WT AMFR partially reconstituted 2'3'-cGAMP-induced STING-mediated signaling and ISG expression in patient PBMCs. This work links defective AMFR-STING signaling to severe VZV disease and hyperinflammation and suggests a direct role for cGAS-STING in the control of viral infections in humans. In conclusion, we describe a novel genetic etiology of severe VZV disease in childhood, also representing the first inborn error of immunity related to a defect in the cGAS-STING pathway.

Diagnostic value of anti-VZV IgG in neurological diseases among varicella unvaccinated individuals.

Varicella zoster virus (VZV) is a neurotropic alphaherpesvirus that causes neurological manifestations either as a complication of primary infection or reactivation. VZV induced neurological diseases have a good prognosis when confirmed early and treated with anti-viral therapy. Myelitis, encephalitis, ventriculitis or meningitis can occur without a telltale rash in immunocompetent and immunocompromised individuals making the diagnosis difficult. We analyzed CSF and serum samples from 30 unvaccinated study participants (17 male and 13 female) to determine the presence of VZV DNA by PCR in CSF and to estimate serum and CSF anti-VZV IgG and albumin levels in participants with neurological manifestations with/without rash. Anti-VZV IgG was detected in CSF (n = 22, [73%]) and serum (n = 29, [97%]) of pediatric and adult participants. Anti-VZV IgG were detected in CSF of participants with varied clinical presentation altered sensorium (n = 8, [36%]), meningitis (n = 4, [18%]), acute febrile illness (n = 3, [14%], encephalopathy/meningoencephalitis (n = 2, [9%]), irritability (n = 2, [9%]) and each patient from cerebrovascular stroke, demyelinating disorder and febrile seizure (n = 1, [4.5%]). VZV DNA was detected from one participant and CSF serum albumin levels were elevated in 53% of study participants. VZV DNA is present up to 1-2 weeks post onset of disease, after which anti-VZV antibody may be the only indicator of disease and therefore both VZV DNA and anti-VZV IgG need to be tested for in CSF. As VZV DNA and VZV IgG antibody are both good indicators of VZV reactivation, routine testing would result in reduced morbidity and mortality by early detection of disease and antiviral treatment.

Modulation of Host Cell Signaling Pathways by Varicella-Zoster Virus.

Host-pathogen interactions involve complex inside-out and outside-in signal transmission through critical cellular networks that dictate disease outcomes. The phosphoinositide 3-kinase (PI3K)/Akt pathway is a pivotal junction that regulates several cell functions, and phospho-Akt (pAkt) is often found to be constitutively active in cancer cells, similar to phospho-STAT3. In this chapter, we discuss the regulation of PI3K/Akt pathway in VZV infected cells and of other pathways including p53 which, unlike pAkt and pSTAT3, directs cells towards apoptosis. The fine spatio-temporal balance of activation of pro- and anti-apoptotic factors during VZV infection likely provides an optimum environment for the virus to replicate and cause disease in the human host.

Upregulation of keratin 15 is required for varicella-zoster virus replication in keratinocytes and is attenuated in the live attenuated vOka vaccine strain.

Varicella-zoster virus (VZV) is the etiological agent of chickenpox and shingles, diseases characterised by epidermal virus replication in skin and mucosa and the formation of blisters. We have previously shown that VZV infection has a profound effect on keratinocyte differentiation, altering the normal pattern of epidermal gene expression. In particular, VZV infection reduces expression of suprabasal keratins 1 and 10 and desmosomal proteins, disrupting epidermal structure to promote expression of a blistering phenotype. Here, we extend these findings to show that VZV infection upregulates the expression of keratin 15 (KRT15), a marker expressed by basal epidermal keratinocytes and hair follicles stem cells. We demonstrate that KRT15 is essential for VZV replication in the skin, since downregulation of KRT15 inhibits VZV replication in keratinocytes, while KRT15 exogenous overexpression supports viral replication. Importantly, our data show that VZV upregulation of KRT15 depends on the expression of the VZV immediate early gene ORF62. ORF62 is the only regulatory gene that is mutated in the live attenuated VZV vaccine and contains four of the five fixed mutations present in the VZV Oka vaccine. Our data indicate that the mutated vaccine ORF62 is not capable of upregulating KRT15, suggesting that this may contribute to the vaccine attenuation in skin. Taken together our data present a novel association between VZV and KRT15, which may open a new therapeutic window for a topical targeting of VZV replication in the skin via modulation of KRT15.

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.

Varicella zoster virus downregulates expression of the non-classical antigen presentation molecule CD1d.

BACKGROUND: The non-classical antigen presentation molecule CD1d presents lipid antigens to invariant natural killer T (iNKT) cells. Activation of these cells triggers a rapid cytokine response providing an interface between innate and adaptive immune responses. The importance of CD1d and iNKT cells in varicella zoster virus (VZV) infection has been emphasised by clinical reports of individuals with CD1d or iNKT cell deficiencies experiencing severe, disseminated varicella post-vaccination. METHODS: Three strains of VZV, VZV-S, rOka, and VZV rOka-66S were used to infect Jurkat cells. Flow cytometry of VZV- and mock-infected cells assessed the modulatory impact of VZV on CD1d. Infected cell-supernatant and transwell coculture experiments explored the role of soluble factors in VZV-mediated immunomodulation. CD1d transcripts were assessed by RT-qPCR. RESULTS: Surface and intracellular flow cytometry demonstrated CD1d was strikingly downregulated by VZV-S and rOka in both infected and VZV antigen-negative cells compared to mock. CD1d downregulation is cell-contact-dependant and CD1d transcripts are targeted by VZV. Mechanistic investigations using rOka-66S (unable to express the viral kinase ORF66), implicate this protein in CD1d modulation in infected cells. CONCLUSIONS: VZV implements multiple mechanisms targeting both CD1d transcript and protein. This provides evidence of VZV interaction with and manipulation of the CD1d-iNKT cell axis.

Varicella Zoster Virus Impairs Expression of the Nonclassical Major Histocompatibility Complex Class I-Related Gene Protein (MR1).

The antigen presentation molecule MR1 (major histocompatibility complex, class I-related) presents ligands derived from the riboflavin (vitamin B) synthesis pathway, which is not present in mammalian species or viruses, to mucosal-associated invariant T (MAIT) cells. In this study, we demonstrate that varicella zoster virus (VZV) profoundly suppresses MR1 expression. We show that VZV targets the intracellular reservoir of immature MR1 for degradation, while preexisting, ligand-bound cell surface MR1 is protected from such targeting, thereby highlighting an intricate temporal relationship between infection and ligand availability. We also identify VZV open reading frame (ORF) 66 as functioning to suppress MR1 expression when this viral protein is expressed during transient transfection, but this is not apparent during infection with a VZV mutant virus lacking ORF66 expression. This indicates that VZV is likely to encode multiple viral genes that target MR1. Overall, we identify an immunomodulatory function of VZV whereby infection suppresses the MR1 biosynthesis pathway.

The impact of HLA polymorphism on herpesvirus infection and disease.

Human Leukocyte Antigens (HLA) are cell surface molecules, central in coordinating innate and adaptive immune responses, that are targets of strong diversifying natural selection by pathogens. Of these pathogens, human herpesviruses have a uniquely ancient relationship with our species, where coevolution likely has reciprocating impact on HLA and viral genomic diversity. Consistent with this notion, genetic variation at multiple HLA loci is strongly associated with modulating immunity to herpesvirus infection. Here, we synthesize published genetic associations of HLA with herpesvirus infection and disease, both from case/control and genome-wide association studies. We analyze genetic associations across the eight human herpesviruses and identify HLA alleles that are associated with diverse herpesvirus-related phenotypes. We find that whereas most HLA genetic associations are virus- or disease-specific, HLA-A*01 and HLA-A*02 allotypes may be more generally associated with immune susceptibility and control, respectively, across multiple herpesviruses. Connecting genetic association data with functional corroboration, we discuss mechanisms by which diverse HLA and cognate receptor allotypes direct variable immune responses during herpesvirus infection and pathogenesis. Together, this review examines the complexity of HLA-herpesvirus interactions driven by differential T cell and Natural Killer cell immune responses.

Live attenuated VZV vaccination induces antitumor immunity in ATLL patients.

Adult T cell leukemia/lymphoma (ATLL) is a CD4-positive peripheral T cell lymphoma caused by human T cell lymphotropic virus type 1 (HTLV-1). Although ATLL is quite difficult to be cured, up-regulation of cellular immunity such as HTLV-1 Tax-specific cytotoxic T lymphocytes (CTLs) has been proved to be important to obtain long-term survival. At present, no efficacious method to activate ATLL-specific cellular immunity is available. This study aimed to investigate whether live attenuated varicella-zoster virus (VZV) vaccination to ATLL can activate HTLV-1 Tax-specific cellular immune response. A total of 3 indolent- and 3 aggressive-type ATLL patients were enrolled. All aggressive-type patients had the VZV vaccination after completing anti-ATLL treatment including mogamulizumab, which is a monoclonal antibody for C-C chemokine receptor 4 antigen, plus combination chemotherapy, whereas all indolent-type patients had the VZV vaccination without any antitumor treatment. Cellular immune responses including Tax-specific CTLs were analyzed at several time points of pre- and post-VZV vaccination. After the VZV vaccination, a moderate increase in 1 of 3 indolent-type patients and obvious increase in all 3 aggressive-type patients in Tax-specific CTLs percentage were observed. The increase in the cell-mediated immunity against VZV was observed in all indolent- and aggressive-type patients after VZV vaccination. To conclude, VZV vaccination to aggressive-type ATLL patients after mogamulizumab plus chemotherapy led to the up-regulation of HTLV-1 Tax-specific CTLs without any adverse event. Suppression of regulatory T lymphocytes by mogamulizumab may have contributed to increase tumor immunity in aggressive-type ATLL patients. Japan Registry of Clinical Trials number, jRCTs051180107.

Exploring the causal role of the immune response to varicella-zoster virus on multiple traits: a phenome-wide Mendelian randomization study.

BACKGROUND: The immune response to infections could be largely driven by the individual's genes, especially in the major histocompatibility complex (MHC) region. Varicella-zoster virus (VZV) is a highly communicable pathogen. In addition to infection, the reactivations of VZV can be a potential causal factor for multiple traits. Identification of VZV immune response-related health conditions can therefore help elucidate the aetiology of certain diseases. METHODS: A phenome-wide Mendelian randomization (MR) study of anti-VZV immunoglobulin G (IgG) levels with 1370 traits was conducted to explore the potential causal role of VZV-specific immune response on multiple traits using the UK Biobank cohort. For the robustness of the results, we performed MR analyses using five different methods. To investigate the impact of the MHC region on MR results, the analyses were conducted using instrumental variables (IVs) inside (IVmhc) and outside (IVno.mhc) the MHC region or all together (IVfull). RESULTS: Forty-nine single nucleotide polymorphisms (IVfull) were associated with anti-VZV IgG levels, of which five (IVmhc) were located in the MHC region and 44 (IVno.mhc) were not. Statistical evidence (false discovery rate < 0.05 in at least three of the five MR methods) for a causal effect of anti-VZV IgG levels was found on 22 traits using IVmhc, while no evidence was found when using IVno.mhc or IVfull. The reactivations of VZV increased the risk of Dupuytren disease, mononeuropathies of the upper limb, sarcoidosis, coeliac disease, teeth problems and earlier onset of allergic rhinitis, which evidence was concordant with the literature. Suggestive causal evidence (P < 0.05 in at least three of five MR methods) using IVfull, IVmhc and IVno.mhc was detected in 92, 194 and 56 traits, respectively. MR results from IVfull correlated with those from IVmhc or IVno.mhc. However, the results between IVmhc and IVno.mhc were noticeably different, as evidenced by causal associations in opposite directions between anti-VZV IgG and ten traits. CONCLUSIONS: In this exploratory study, anti-VZV IgG was causally associated with multiple traits. IVs in the MHC region might have a substantial impact on MR, and therefore, could be potentially considered in future MR studies.

Alterations in pathogen-specific cellular and humoral immunity associated with acute peripheral facial palsy of infectious origin.

BACKGROUND: Peripheral facial palsy (PFP) is a common neurologic symptom which can be triggered by pathogens, autoimmunity, trauma, tumors, cholesteatoma or further local conditions disturbing the peripheral section of the nerve. In general, its cause is often difficult to identify, remaining unknown in over two thirds of cases. As we have previously shown that the quantity and quality of pathogen-specific T cells change during active infections, we hypothesized that such changes may also help to identify the causative pathogen in PFPs of unknown origin. METHODS: In this observational study, pathogen-specific T cells were quantified in blood samples of 55 patients with PFP and 23 healthy controls after stimulation with antigens from varicella-zoster virus (VZV), herpes-simplex viruses (HSV) or borrelia. T cells were further characterized by expression of the inhibitory surface molecule CTLA-4, as well as markers for differentiation (CD27) and proliferation (Ki67). Pathogen-specific antibody responses were analyzed using ELISA. Results were compared with conventional diagnostics. RESULTS: Patients with PFP were more often HSV-seropositive than controls (p = 0.0003), whereas VZV- and borrelia-specific antibodies did not differ between groups. Although the quantity and general phenotypical characteristics of antigen-specific T cells did not differ either, expression of CTLA-4 and Ki67 was highly increased in VZV-specific T cells of 9 PFP patients, of which 5 showed typical signs of cutaneous zoster. In the remaining 4 patients, a causal relationship with VZV was possible but remained unclear by clinical standard diagnostics. A similar CTLA-4- and Ki67-expression profile of borrelia-specific T cells was also found in a patient with acute neuroborreliosis. DISCUSSION: In conclusion, the high prevalence of HSV-seropositivity among PFP-patients may indicate an underestimation of HSV-involvement in PFP, even though HSV-specific T cell characteristics seem insufficient to identify HSV as a causative agent. In contrast, striking alterations in VZV- and borrelia-specific T cell phenotype and function may allow identification of VZV- and borrelia-triggered PFPs. If confirmed in larger studies, antigen-specific immune-phenotyping may have the potential to improve specificity of the clinical diagnosis.

Analysis of the reliability of rapid diagnostic tests for varicella, including breakthrough cases.

In the era of universal varicella vaccination, diagnosis of varicella is challenging, especially for breakthrough cases. We sought to clarify the reliability of direct varicella-zoster virus (VZV) loop-mediated isothermal amplification (LAMP) and DermaQuick® VZV using the immunochromatography technique as rapid diagnostic tests for varicella. In addition, the usefulness of saliva as a sample type for direct LAMP was investigated. Among the 46 enrolled patients with suspected VZV infection, 31 patients (67.3%) were positive for the nucleic acid test based on real-time PCR from skin swab samples. Direct LAMP of skin swabs was positive in 29 (63.0%) of 46 patients. DermaQuick® VZV was positive in 25 (54.3%) of 46 patients. VZV DNA was detected in only 48.4% of oral swabs with the direct LAMP method. With real-time polymerase chain reaction (PCR) as the standard for diagnosing varicella, the sensitivity and specificity of DermaQuick® VZV were 80.7% and 100%, respectively. The sensitivity and specificity of direct LAMP from skin swabs were 93.6% and 100%, respectively. The sensitivity and specificity of real-time PCR for DNA extracted from oral swabs were 74.2% and 93.3%, respectively. Thus, oral swab samples are not suitable for breakthrough varicella diagnosis. Although DermaQuick® VZV is considered the most convenient point-of-care test for varicella, its sensitivity and specificity were lower than those of direct VZV LAMP.

Progressive shingles in a toddler due to reactivation of Varicella Zoster vaccine virus four days after infection with SARS-CoV-2; a case report.

BACKGROUND: Herpes zoster (HZ) is the clinical syndrome associated with reactivation of latent varicella-zoster virus (VZV). Several factors have been implicated to promote VZV reactivation; these include immunosuppression, older age, mechanical trauma, physiologic stress, lymphopenia, and more recently, infection with severe acute respiratory syndrome coronavirus-2 (SARS- CoV-2). Recent reports suggest an increase in the number of HZ cases in the general population during the global COVID-19 pandemic. However, it is unknown what proportion of HZ during the pandemic is due to reactivation of wild-type or vaccine-strain VZV. CASE: Here we report the first known case of HZ concomitant with SARS-CoV2 infection in a 20-month-old female who was treated with a single dose of dexamethasone, due to reactivation of the vaccine-type strain of VZV after presenting with a worsening vesicular rash. CONCLUSION: In this case, we were able to show vaccine-strain VZV reactivation in the context of a mild acute symptomatic COVID-19 infection in a toddler. Being able to recognize HZ quickly and effectively in a pediatric patient can help stave off the significant morbidity and mortality associated with disease process.

Case report: Hospital-acquired chickenpox in a healthcare setting.

Chickenpox (varicella) is a rare occurrence in healthcare settings in the USA, but can be transmitted to healthcare workers (HCWs) from patients with herpes zoster who, in turn, can potentially transmit it further to unimmunized, immunosuppressed, at-risk, vulnerable patients. It is uncommon due to the inclusion of varicella vaccination in the recommended immunization schedule for children and screening for varicella immunity in HCWs during employment. We present a case report of hospital-acquired chickenpox in a patient who developed the infection during his prolonged hospital stay through a HCW who had contracted chickenpox after exposure to our patient's roommate with herpes zoster. There was no physical contact between the roommates, but both patients had a common HCW as caregiver. The herpes zoster patient was placed in airborne precautions immediately, but the HCW continued to work and have physical contact with our patient. The HCW initially developed chickenpox 18 days after exposure to the patient with herpes zoster, and our patient developed chickenpox 17 days after the HCW. The timeline and two incubation periods, prior to our patient developing chickenpox, indicate transmission of chickenpox in the HCW from exposure to the herpes zoster patient and subsequently to our patient. The case highlights the potential for nosocomial transmission of chickenpox (varicella) to unimmunized HCWs from exposure to patients with herpes zoster and further transmission to unimmunized patients. Verification of the immunization status of HCWs at the time of employment, mandating immunity, furloughing unimmunized staff after exposure to herpes zoster, and postexposure prophylaxis with vaccination or varicella zoster immunoglobulin (Varizig) will minimize the risk of transmission of communicable diseases like chickenpox in healthcare settings. Additionally, establishing patients' immunity, heightened vigilance and early identification of herpes zoster in hospitalized patients, and initiation of appropriate infection control immediately will further prevent such occurrences and improve patient safety.This is a case report of a varicella-unimmunized 31-year-old patient who developed chickenpox during his 80-day-long hospitalization. He had different roommates during his long hospital stay but had no physical contact with them and neither had visitors. On most days, the same HCW rendered care to him and his roommates. One of the patient's roommates was found to have herpes zoster and was immediately moved to a different room with appropriate infection prevention measures. The HCW is presumably unimmunized to varicella and sustained significant exposure to the patient with herpes zoster during routine patient care which involved significant physical contact. The HCW was not furloughed, assessed for immunity, or given postexposure prophylaxis (PEP). The HCW had continued contact with our patient as part of routine care. On day 18, after exposure to the patient with herpes zoster, the HCW developed chickenpox. 17 days thereafter, our patient developed chickenpox. The time interval of chickenpox infection in the HCW after one incubation period after exposure to the patient with herpes zoster followed by a similar infection of chickenpox in our patient after another incubation period suggests the spread of varicella zoster virus (VZV) from the herpes zoster patient to the HCW and further from the HCW to our patient. Assessing the immunity of HCWs to varicella at the time of employment, ensuring only HCWs with immunity take care of herpes zoster and varicella patients, furloughing unimmunized exposed HCWs, offering PEP, and documentation of patients' immunity to varicella at the time of hospital admission could help prevent VZV transmission in hospital settings. This is an attempt to publish this novel case due to its high educational value and relevant learning points.

Hematopoietic stem cell transplantation and the noncytomegalovirus herpesviruses.

Although hematopoietic stem cell transplantation (HSCT) and other cellular therapies have significantly improved outcomes in the management of multiple hematological and nonhematological malignancies, the resulting impairment in humoral and cellular response increases the risk for opportunistic infection as an undesirable side effect. With their ability to establish latent infection and reactivate when the host immune system is at its weakest point, the Herpesviridae family constitutes a significant proportion of these opportunistic pathogens. Despite recent advancements in preventing and managing herpesvirus infections, they continue to be a common cause of significant morbidity and mortality in transplanted patients. Herein, we aim to provide and update on herpesvirus other than cytomegalovirus (CMV) affecting recipients of HSCT and other cellular therapies.