Genital herpes

Pathogenesis of viral infections during pregnancy

SUMMARYViral infections during pregnancy are associated with significant adverse perinatal and fetal outcomes. Pregnancy is a unique immunologic and physiologic state, which can influence control of virus replication, severity of disease, and vertical transmission. The placenta is the organ of the maternal-fetal interface and provides defense against microbial infection while supporting the semi-allogeneic fetus via tolerogenic immune responses. Some viruses, such as cytomegalovirus, Zika virus, and rubella virus, can breach these defenses, directly infecting the fetus and having long-lasting consequences. Even without direct placental infection, other viruses, including respiratory viruses like influenza viruses and severe acute respiratory syndrome coronavirus 2, still cause placental damage and inflammation. Concentrations of progesterone and estrogens rise during pregnancy and contribute to immunological adaptations, placentation, and placental development and play a pivotal role in creating a tolerogenic environment at the maternal-fetal interface. Animal models, including mice, nonhuman primates, rabbits, and guinea pigs, are instrumental for mechanistic insights into the pathogenesis of viral infections during pregnancy and identification of targetable treatments to improve health outcomes of pregnant individuals and offspring.

Function of autophagy genes in innate immune defense against mucosal pathogens

Mucosal immunity is posed to constantly interact with commensal microbes and invading pathogens. As a fundamental cell biological pathway affecting immune response, autophagy regulates the interaction between mucosal immunity and microbes through multiple mechanisms, including direct elimination of microbes, control of inflammation, antigen presentation and lymphocyte homeostasis, and secretion of immune mediators. Some of these physiologically important functions do not involve canonical degradative autophagy but rely on certain autophagy genes and their 'autophagy gene-specific functions.' Here, we review the relationship between autophagy and important mucosal pathogens, including influenza virus, Mycobacterium tuberculosis, Salmonella enterica, Citrobacter rodentium, norovirus, and herpes simplex virus, with a particular focus on distinguishing the canonical versus gene-specific mechanisms of autophagy genes.

Prevalence of yaws and syphilis in the Ashanti region of Ghana and occurrence of H. ducreyi, herpes simplex virus 1 and herpes simplex virus 2 in skin lesions associated with treponematoses

Yaws affects children in tropical regions, while syphilis primarily affects sexually active adults worldwide. Despite various campaigns towards the eradication of yaws and elimination of syphilis, these two diseases are still present in Ghana. The aetiological agents of both diseases, two Treponema pallidum subspecies, are genetically similar. This study aimed to assess the prevalence of these treponematoses and the occurrence of pathogens causing similar skin lesions in the Ashanti region of Ghana. A point-of-care test was used to determine the seroprevalence of the treponematoses. Both yaws and syphilis were identified in the Ashanti region of Ghana. Multiplex PCR was used to identify treponemes and other pathogens that cause similar skin lesions. The results indicated that the seroprevalences of T. pallidum in individuals with yaws-like and syphilis-like lesions were 17.2% and 10.8%, respectively. Multiplex PCR results showed that 9.1%, 1.8% and 0.9% of yaws-like lesions were positive for Haemophilus ducreyi, herpes simplex virus-1 (HSV-1) and T. pallidum respectively. Among syphilis-like lesions, 28.3% were positive for herpes simplex virus -2 (HSV-2) by PCR. To our knowledge, this is the first time HSV-I and HSV-2 have been reported from yaws-like and syphilis-like lesions, respectively, in Ghana. The presence of other organisms apart from T. pallidum in yaws-like and syphilis-like lesions could impede the total healing of these lesions and the full recovery of patients. This may complicate efforts to achieve yaws eradication by 2030 and the elimination of syphilis and warrants updated empirical treatment guidelines for skin ulcer diseases.

Single domain antibodies from camelids in the treatment of microbial infections

Infectious diseases continue to pose significant global health challenges. In addition to the enduring burdens of ailments like malaria and HIV, the emergence of nosocomial outbreaks driven by antibiotic-resistant pathogens underscores the ongoing threats. Furthermore, recent infectious disease crises, exemplified by the Ebola and SARS-CoV-2 outbreaks, have intensified the pursuit of more effective and efficient diagnostic and therapeutic solutions. Among the promising options, antibodies have garnered significant attention due to their favorable structural characteristics and versatile applications. Notably, nanobodies (Nbs), the smallest functional single-domain antibodies of heavy-chain only antibodies produced by camelids, exhibit remarkable capabilities in stable antigen binding. They offer unique advantages such as ease of expression and modification and enhanced stability, as well as improved hydrophilicity compared to conventional antibody fragments (antigen-binding fragments (Fab) or single-chain variable fragments (scFv)) that can aggregate due to their low solubility. Nanobodies directly target antigen epitopes or can be engineered into multivalent Nbs and Nb-fusion proteins, expanding their therapeutic potential. This review is dedicated to charting the progress in Nb research, particularly those derived from camelids, and highlighting their diverse applications in treating infectious diseases, spanning both human and animal contexts.

Neonatal herpes: case series in two obstetric centres over a 10-year period (2013-2023), France

Neonatal herpes simplex virus (HSV) infection (HSV infection in infants less than 6 weeks of age) is rare but mortality and morbidity rates are high after disseminated disease and encephalitis. In France, the epidemiology is poorly described, and two decades ago, incidence was estimated to be 3 per 100,000 live births a year. We describe determinants, epidemiologic and clinical characteristics of neonatal HSV infection in a managed-care population attending in two major obstetric and paediatric centres, Paris, France, over a 10-year period. This retrospective case series study was conducted from 2013 to 2023, in infants less than 42 days of age who had virologically confirmed HSV infection. We report an overall rate of neonatal herpes of 5.5 per 100,000 live births a year and an incidence of symptomatic cases of 1.2 per 100,000 live births a year. HSV-1 was the major serotype involved (84.2%) and post-natal acquisition through the orolabial route reached 63.2%. All neonates who had neonatal HSV PCR screening (owing to clinical signs in parents) and who received prompt acyclovir treatment remained asymptomatic. Symptomatic forms accounted for 21.1% cases of the total and mortality was high (62.5% of symptomatic forms).   Conclusion: This case series confirms that neonates at risk for HSV disease and poor outcome are those born to HSV-seronegative mothers, preterm infants, and those who received acyclovir after onset of symptoms (mainly because mothers did not present evidence of acute HSV infection). Our study confirms the major role of HSV-1 and the frequency of its early post-natal acquisition. What is known: • Neonatal herpes simplex virus infection is rare but motality and morbidity rates are high after disseminted disease and encephalitis. National recommendations exist worldwide but mangement of this disease is not always easy. What is new: • As in France epidemiology of neonatal herpes is poorly described, our report is potentially an important addition to the existing literature. Moreover, we describe local practice that may be useful to physicians.

Influence of connatural factors in shaping vaginal microflora and ensuring its health

Vaginal canal (VC) is exposed to the external environment affected by habitual factors like hygiene and sexual behaviour as well as physiological factors like puberty, menstrual cycle, pregnancy, child birth and menopause. Healthy VC harbours beneficial microflora supported by vaginal epithelium and cervical fluid. Connatural antimicrobial peptide (AMPs) of female reproductive tract (FRT) conjunctly with these beneficial microbes provide protection from a large number of infectious diseases. Such infections may either be caused by native microbes of the VC or transitory microbes like bacteria or virus which are not a part of VC microflora. This review highlight's the role of hormones, enzymes, innate immunological factors, epithelial cells and vaginal mucus that support beneficial microbes over infectious ones thus, helping to maintain homeostasis in VC and further protect the FRT. We also discuss the prospective use of vaginal probiotics and AMPs against pathogens which can serve as a potential cure for vaginal infections.

The HIF transcription network exerts innate antiviral activity in neurons and limits brain inflammation

Pattern recognition receptors (PRRs) induce host defense but can also induce exacerbated inflammatory responses. This raises the question of whether other mechanisms are also involved in early host defense. Using transcriptome analysis of disrupted transcripts in herpes simplex virus (HSV)-infected cells, we find that HSV infection disrupts the hypoxia-inducible factor (HIF) transcription network in neurons and epithelial cells. Importantly, HIF activation leads to control of HSV replication. Mechanistically, HIF activation induces autophagy, which is essential for antiviral activity. HSV-2 infection in vivo leads to hypoxia in CNS neurons, and mice with neuron-specific HIF1/2α deficiency exhibit elevated viral load and augmented PRR signaling and inflammatory gene expression in the CNS after HSV-2 infection. Data from human stem cell-derived neuron and microglia cultures show that HIF also exerts antiviral and inflammation-restricting activity in human CNS cells. Collectively, the HIF transcription factor system senses virus-induced hypoxic stress to induce cell-intrinsic antiviral responses and limit inflammation.

Development of recombinant rotavirus carrying herpes simplex virus 2 glycoprotein D gene based on reverse genetics technology

Vaccine development for herpes simplex virus 2 (HSV-2) has been attempted, but no vaccines are yet available. A plasmid-based reverse genetics system for Rotavirus (RV), which can cause gastroenteritis, allows the generation of recombinant RV containing foreign genes. In this study, we sought to develop simian RV (SA11) as a vector to express HSV-2 glycoprotein D (gD2) and evaluated its immunogenicity in mice. We generated the recombinant SA11-gD2 virus (rSA11-gD2) and confirmed its ability to express gD2 in vitro. The virus was orally inoculated into suckling BALB/c mice and into 8-week-old mice. Serum IgG and IgA titers against RV and gD2 were measured by ELISA. In the 8-week-old mice inoculated with rSA11-gD2, significant increases in not only antibodies against RV but also IgG against gD2 were demonstrated. In the suckling mice, antibodies against RV were induced, but gD2 antibody was not detected. Diarrhea observed after the first inoculation of rSA11-gD2 in suckling mice was similar to that induced by the parent virus. A gD2 expressing simian RV recombinant, which was orally inoculated, induced IgG against gD2. This strategy holds possibility for genital herpes vaccine development.

Diagnostic Methods and Management Strategies of Herpes Simplex and Herpes Zoster Infections

Herpesviruses are medium-sized double-stranded DNA viruses. Of more than 80 herpesviruses identified, only 9 human herpesviruses have been found to cause infection in humans. These include herpes simplex viruses 1 and 2 (HSV-1 and HSV-2), varicella-zoster virus (VZV), human cyto-megalovirus (HCMV), Epstein-Barr virus (EBV), and human herpesvirus (HHV-6A, HHV-6B, HHV-7, HHV-8). HSV-1, HSV-2, and VZV can be problematic given their characteristic neurotropism which is the ability to invade via fusion of its plasma membrane and reside within neural tissue. HSV and VZV primarily infect mucocutaneous surfaces and remain latent in the dorsal root ganglia for a host's entire life. Reactivation causes either asymptomatic shedding of virus or clinical manifestation of vesicular lesions. The clinical presentation is influenced by the portal of entry, the immune status of the host, and whether the infection is primary or recurrent. Affecting 60% to 95% of adults, herpesvirus-associated infections include gingivostomatitis, orofacial and genital herpes,and primary varicella and herpes zoster. Symptomatology, treatment, and potential complications vary based on primary and recurrent infections as well as the patient's immune status.

A rapid isothermal CRISPR-Cas13a diagnostic test for genital herpes simplex virus infection

Prompt diagnosis is essential for managing herpes simplex virus types 1 and 2 (HSV-1/2). Existing diagnostic methods are not widely available that required expensive or additional equipment for conducting examinations and result readouts, which can limit their utility in resource-constrained settings. We successfully developed a CRISPR-Cas13a-based assay for the detection and genotyping of HSV. Our assay demonstrated a high sensitivity of 96.15% and 95.15% for HSV-1 and HSV-2, respectively, with a specificity of 100% compared to a commercial qPCR assay when tested on 194 clinical samples. Remarkably, the assay enables a limit of detection of 1 copy/μL of viral DNA, facilitated by an enhanced input of RPA product and is designed for both mobile app integration and colorimetric interpretation, allowing for semiquantitative readings. These findings highlight the excellent performance of our CRISPR-based diagnostic in detecting HSV and its potential for point-of-care testing in resource-constrained settings.

Immunogenicity and Therapeutic Efficacy of a Sendai-Virus-Vectored HSV-2 Vaccine in Mouse and Guinea Pig Models

BACKGROUND

To date, there is no licensed vaccine for preventing herpes simplex virus type 2 (HSV-2). The current treatment to address the infection and prevent its transmission is not always satisfactory.

METHODS

We constructed two recombinant vectors, one encoding HSV-2 glycoprotein D (gD, SeV-dF/HSV-2-gD) and one encoding HSV-2-infected cell protein 27 (ICP27, SeV-dF/HSV-2-ICP27), based on a replication-defective Sendai virus through reverse genetics, collectively comprising a combinatorial HSV-2 therapeutic vaccine candidate. The immunogenicity and proper immunization procedure for this vaccine were explored in a murine model. The therapeutic effect that helps prevent recurrent HSV-2 disease was evaluated in HSV-2-infected guinea pigs.

RESULTS

Both a robust humoral immune response and a cellular immune response, characterized by the neutralizing antibody titer and the IFN-γ level, respectively, were elicited in BALB/c mice. A further study of cellular immunogenicity in mice revealed that T lymphocytes were successfully enhanced with the desirable secretion of several cytokines. In HSV-2-seropositive guinea pigs, vaccination could reduce the severity of HSV-2 in terms of recurrent lesions, duration of recurrent outbreak, and frequency of recurrence by 58.66%, 45.34%, and 45.09%, respectively, while viral shedding was also significantly inhibited in the vaccine-treated group compared to the group treated with phosphate-buffered saline.

CONCLUSIONS

The replication-defective recombinant Sendai viruses conveying HSV-2-gD and ICP27 proteins showed great immunogenicity and potential for preventing recurrent HSV-2 disease.

Age Patterns of HSV-2 Incidence and Prevalence in Two Ugandan Communities: A Catalytic Incidence Model Applied to Population-Based Seroprevalence Data

BACKGROUND

Herpes simplex virus type 2 (HSV-2) is an incurable sexually transmitted infection associated with increased risk of acquiring and transmitting human immunodeficiency virus (HIV). HSV-2 is highly prevalent in sub-Saharan Africa, but population-level estimates of incidence are sparse.

METHODS

We measured HSV-2 prevalence from cross-sectional serological data among adults aged 18-49 years in 2 south-central Uganda communities (fishing, inland). We identified risk factors for seropositivity, then inferred age patterns of HSV-2 with a Bayesian catalytic model.

RESULTS

HSV-2 prevalence was 53.6% (n = 975/1819; 95% confidence interval, 51.3%-55.9%). Prevalence increased with age, was higher in the fishing community, and among women, reaching 93.6% (95% credible interval, 90.2%-96.6%) by age 49 years. Factors associated with HSV-2 seropositivity included more lifetime sexual partners, HIV positive status, and lower education. HSV-2 incidence peakied at age 18 years for women and 19-20 years for men. HIV prevalence was up to 10-fold higher in HSV-2-positive individuals.

CONCLUSIONS

HSV-2 prevalence and incidence were extremely high, with most infections occurring in late adolescence. Interventions against HSV-2, such as future vaccines or therapeutics, must target young populations. Remarkably higher HIV prevalence among HSV-2-positive individuals underscores this population as a priority for HIV prevention.

Mechanism of herpesvirus UL24 protein regulating viral immune escape and virulence

Herpesviruses have evolved a series of abilities involved in the process of host infection that are conducive to virus survival and adaptation to the host, such as immune escape, latent infection, and induction of programmed cell death for sustainable infection. The herpesvirus gene UL24 encodes a highly conserved core protein that plays an important role in effective viral infection. The UL24 protein can inhibit the innate immune response of the host by acting on multiple immune signaling pathways during virus infection, and it also plays a key role in the proliferation and pathogenicity of the virus in the later stage of infection. This article reviews the mechanism by which the UL24 protein mediates herpesvirus immune escape and its effects on viral proliferation and virulence by influencing syncytial formation, DNA damage and the cell cycle. Reviewing these studies will enhance our understanding of the pathogenesis of herpesvirus infection and provide evidence for new strategies to combat against viral infection.

Successful Confirmation of Dual Genital Herpes Co-Infection with Herpes Simplex Virus 1 and Herpes Simplex Virus 2 Using Unbiased Metagenomic Next-Generation Sequencing

Dual co-infection with both HSV-1 and HSV-2 is rare, with few cases reported in the literature. In this case report, we describe the successful use of unbiased metagenomic next-generation sequencing (mNGS) as a rapid and alternative method for confirming dual genital herpes co-infection. Our case involves a 74-year-old woman who presented with genital lesions and initially tested positive for both HSV-1 and HSV-2 via the Luminex ARIES HSV 1&2 assay. The entire mNGS process, from nucleic acid extraction to result analysis, was completed in less than 48 h. Using mNGS, we identified mapped reads specific to either HSV-1 or HSV-2 and screened the sequences to rule out mis-genotyping by the Luminex ARIES assay. Notably, the generated sequences can reveal sequence variations within multiple gene regions, demonstrating the potential of mNGS for identifying novel HSV-1 and HSV-2 variants. Our findings suggest that mNGS can serve as a rapid and reliable alternative confirmatory method for dual genital herpes infections, providing valuable information to guide appropriate treatment options for patients. By eliminating the need for prior knowledge of causative agents, mNGS offers an unbiased approach for detecting and characterizing viral co-infections.

Mechanistic insights into the role of herpes simplex virus 1 in Alzheimer's disease

Alzheimer's Disease (AD) is an aging-associated neurodegenerative disorder, threatening millions of people worldwide. The onset and progression of AD can be accelerated by environmental risk factors, such as bacterial and viral infections. Human herpesviruses are ubiquitous infectious agents that underpin numerous inflammatory disorders including neurodegenerative diseases. Published studies concerning human herpesviruses in AD imply an active role HSV-1 in the pathogenesis of AD. This review will summarize the current understanding of HSV-1 infection in AD and highlight some barriers to advance this emerging field.

Lactobacillus rhamnosus GG Regulates Host IFN-I Through the RIG-I Signalling Pathway to Inhibit Herpes Simplex Virus Type 2 Infection

Numerous recent studies have demonstrated that the commensal microbiota plays an important role in host immunity against infections. During the infection process, viruses can exhibit substantial and close interactions with the commensal microbiota. However, the associated mechanism remains largely unknown. Therefore, in this study, we explored the specific mechanisms by which the commensal microbiota modulates host immunity against viral infections. We found that the expression levels of type I interferon (IFN-I) and antiviral priming were significantly downregulated following the depletion of the commensal microbiota due to treatment with broad-spectrum antibiotics (ABX). In addition, we confirmed a unique molecular mechanism underlying the induction of IFN-I mediated by the commensal microbiota. In vivo and in vitro experiments confirmed that Lactobacillus rhamnosus GG (LGG) can suppress herpes simplex virus type 2 (HSV-2) infection by inducing IFN-I expression via the retinoic acid-inducible gene-I (RIG-I) signalling pathway. Therefore, the commensal microbiota-induced production of IFN-I provides a potential therapeutic approach to combat viral infections. Altogether, understanding the complexity and the molecular aspects linking the commensal microbiota to health will help provide the basis for novel therapies already being developed.

Mpox: an updated review of dermatological manifestations in the current outbreak

Mpox is a disease caused by a double-stranded DNA orthopoxvirus discovered in 1958. In 2022, an outbreak on an unprecedented scale marked its transition from neglected, zoonotic disease circulating almost exclusively within African borders to sexually transmitted infection (STI) of international concern. Although phylogenetic evidence suggests progressive evolution from the strain associated with the 2018 outbreak in Nigeria, epidemiological links with previous cases have still not been completely elucidated. Clinically, mpox presents with systemic symptoms, such as fever, headache, malaise and a characteristic cutaneous eruption, similar to that of cognate viruses (e.g. smallpox). Mpox pseudopustules evolve through several stages, including umbilication and crusting, and resolve in the span of 2-3 weeks. The hallmarks that set the 2022 outbreak apart from classic mpox were a disproportionate number of cases occurring in men who have sex with men, an often localized cutaneous picture and a significant burden in terms of concomitant STIs. Investigations into the disease pathogenesis, related immune response, clinical and dermoscopic features, in addition to studies aimed at defining novel management strategies, have advanced mpox knowledge considerably. Herein, recent findings on mpox are reviewed, with a keen focus on dermatological manifestations and their implications in the current diagnostic scenario, reinforcing the pivotal role of dermatologists in managing suspect cases and preventing further spread of the contagion.

Seroprevalence of herpes simplex virus type 1 and type 2 among the migrant workers in Qatar

BACKGROUND

Limited data exists on herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections in migrant populations. This study investigated HSV-1 and HSV-2 seroprevalences and associations among craft and manual workers (CMWs) in Qatar who constitute 60% of Qatar's population.

METHODS

A national population-based cross-sectional seroprevalence survey was conducted on the CMW population, all men, between July 26 and September 9, 2020. 2,612 sera were tested for anti-HSV-1 IgG antibodies using HerpeSelect 1 ELISA IgG kits and for anti-HSV-2 IgG antibodies using HerpeSelect 2 ELISA IgG kits (Focus Diagnostics, USA). Univariable and multivariable logistic regression analyses were conducted to identify associations with HSV-1 and HSV-2 infections.

RESULTS

Serological testing identified 2,171 sera as positive, 403 as negative, and 38 as equivocal for HSV-1 antibodies, and 300 sera as positive, 2,250 as negative, and 62 as equivocal for HSV-2 antibodies. HSV-1 and HSV-2 seroprevalences among CMWs were estimated at 84.2% (95% CI 82.8-85.6%) and 11.4% (95% CI 10.1-12.6%), respectively. HSV-1 infection was associated with nationality, educational attainment, and occupation. HSV-2 infection was associated with age, nationality, and educational attainment.

CONCLUSIONS

Over 80% of CMWs are infected with HSV-1 and over 10% are infected with HSV-2. The findings highlight the need for sexual health programs to tackle sexually transmitted infections among the CMW population.

Epidemiology of herpes simplex virus type 1 in Canada: systematic review, meta-analyses, and meta-regressions

Background

The objective of this study was to characterize herpes simplex virus type 1 (HSV-1) epidemiology in Canada.

Methods

HSV-1 publications as recent as December 6, 2021 were systematically reviewed, synthesized, and reported following PRISMA guidelines. Meta-analyses and meta-regressions were conducted.

Results

HSV-1 measures were extracted from 22 studies and included 32 overall seroprevalence measures (79 stratified), 2 overall proportions of HSV-1 detection in clinically diagnosed genital ulcer disease (2 stratified), and 8 overall proportions of HSV-1 detection in laboratory-confirmed genital herpes (27 stratified). Pooled mean seroprevalence was 19.1% [95% confidence interval (CI): 12.6-26.4%] among healthy children and 51.4% (95% CI: 47.3-55.5%) among healthy adults. Pooled mean seroprevalence among healthy general populations increased with age, with the lowest being 35.7% (95% CI: 29.1-42.6%) among individuals <20 years of age, and the highest being 70.0% (95% CI: 54.8-83.2) among individuals ≥40 years. Seroprevalence increased by 1.02-fold (95% CI: 1.01-1.04) per year. Pooled mean proportion of HSV-1 detection in genital ulcer disease was 30.8% (95% CI: 12.6-52.8%). Pooled mean proportion of HSV-1 detection in genital herpes was 37.4% (95% CI: 29.5-45.6%) and was highest in women and in young persons. Proportion of HSV-1 detection in genital herpes increased by 1.04-fold (95% CI: 1.00-1.08) per year.

Conclusions

HSV-1 epidemiology in Canada appears to be shifting toward less oral acquisition in childhood and more genital acquisition in adulthood, particularly among youth. Both HSV-1 seroprevalence and proportion of HSV-1 detection in genital herpes are increasing with time.

In Vitro Activity of Ozone/Oxygen Gaseous Mixture against a Caprine Herpesvirus Type 1 Strain Isolated from a Goat with Vaginitis

Alphaherpesviruses cause genital lesions and reproductive failure in both humans and animals. Their control is mainly based on prevention using hygienic prophylactic measures due to the absence of vaccines and limitations of antiviral drug therapy. Ozone is an oxidating gas showing a strong microbicidal activity on bacteria, fungi, viruses, and protozoa. The present study assessed the in vitro virucidal and antiviral activity of ozone against caprine herpesvirus type 1 (CpHV-1). The virucidal activity of a gaseous mixture containing O₃ at 20 and 50 μg/mL was assessed against the virus at different contact times (30 s, 60 s, 90 s, 120 s, 180 s, and 300 s). Antiviral activity of a gaseous mixture containing O₃ at 20 and 50 μg/mL was evaluated against the virus after 30 s and 60 s. Ozone displayed significant virucidal activity when used at all the tested concentrations whilst significant antiviral activity was observed using ozone at 50 μg/mL. The gaseous mixture, tested in the present study, showed virucidal and antiviral activity against CpHV-1 in a dose- and time contact-dependent fashion. Ozone therapy could be evaluated in vivo for the treatment of CpHV-1-induced genital lesions in goats using topical applications.

HSV-1 Glycoprotein D and Its Surface Receptors: Evaluation of Protein-Protein Interaction and Targeting by Triazole-Based Compounds through In Silico Approaches

Protein-protein interactions (PPI) represent attractive targets for drug design. Thus, aiming at a deeper insight into the HSV-1 envelope glycoprotein D (gD), protein-protein docking and dynamic simulations of gD-HVEM and gD-Nectin-1 complexes were performed. The most stable complexes and the pivotal key residues useful for gD to anchor human receptors were identified and used as starting points for a structure-based virtual screening on a library of both synthetic and designed 1,2,3-triazole-based compounds. Their binding properties versus gD interface with HVEM and Nectin-1 along with their structure-activity relationships (SARs) were evaluated. Four [1,2,3]triazolo[4,5-b]pyridines were identified as potential HSV-1 gD inhibitors, for their good theoretical affinity towards all conformations of HSV-1 gD. Overall, this study suggests promising basis for the design of new antiviral agents targeting gD as a valuable strategy to prevent viral attachment and penetration into the host cell.

Effects of Melatonin Alone or Associated with Acyclovir on the Suppressive Treatment of Recurrent Genital Herpes: A Prospective, Randomized, and Double-Blind Study

Suppressive therapy of recurrent genital herpes is a challenge, and melatonin may be an alternative. Objective: To evaluate the action of melatonin, acyclovir, or the association of melatonin with acyclovir as a suppressive treatment in women with recurrent genital herpes. Design: The study was prospective, double-blind, and randomized, including 56 patients as follows: (a) The melatonin group received 180 placebo capsules in the ‘day’ container and 180 melatonin 3 mg capsules in the ‘night’ container (n = 19); (b) The acyclovir group received 360 capsules of 400 mg acyclovir twice a day (one capsule during the day and another during the night) (n = 15); (c) the melatonin group received 180 placebo capsules in the ‘day’ container and 180 melatonin 3 mg capsules in the ‘night’ container (n = 22). The length of treatment was six months. The follow-up after treatment was six months. Patients were evaluated before, during, and after treatment through clinical visits, laboratory tests, and the application of four questionnaires (QSF-36, Beck, Epworth, VAS, and LANNS). Results: No statistically significant difference was observed for the depression and sleepiness questionnaires. However, in the Lanns scale for pain, all groups decreased the mean and median values in time (p = 0.001), without differentiation among the groups (p = 0.188). The recurrence rates of genital herpes within 60 days after treatment were 15.8%, 33.3%, and 36.4% in the melatonin, acyclovir, and association of melatonin with acyclovir groups, respectively. Conclusion: Our data suggest that melatonin may be an option for the suppressive treatment of recurrent genital herpes.

Epidemiological Survey of Human Alphaherpesvirus 2 (HSV-2) Infection in Indigenous People of Dourados Municipality, Central Brazil

Sexually transmitted Human alphaherpesvirus 2 (HSV-2) causes genital ulcers, especially among sexually active adolescents and adults. We estimated the exact prevalence of anti-HSV-2 antibodies and correlated it with the demographic and behavioral aspects of the Indigenous population of the Jaguapirú and Bororó villages (Dourados, Mato Grosso do Sul (MS), Brazil). In total, 1360 individuals (>18 years old) were administered serologic tests. The prevalence of anti-HSV-2 IgM was 12.9%, that of anti-HSV-2 IgG was 57.2%, and 8.5% cases tested positive for both HSV-2 IgM and IgG. The prevalence of anti-HSV-2 antibodies was higher in females (59.5%) compared to males (49%), with an OR of 0.64 (0.49-0.83). Anti-HSV-2 antibodies were found in 14.2%, 12.3%, 15.4%, and 14.5% of participants with urinary problems, genital wounds, genital warts, and urethral discharge, respectively. In summary, the seroprevalence of HSV-2 in the Indigenous population was five times higher than that reported in the general adult Brazilian population. Educational level, income level, smoking, condom use, incarceration, illicit drug abuse, the sharing of used needles and syringes without adequate disinfection, homosexual relationships, prostitution, the sexual practices among drug users, and avoidance of contraceptive methods could contribute to the facilitation of HSV-2 transmission in the Indigenous population. Our results may help develop culturally appropriate intervention programs that eliminate health-access barriers and improve the implementation of public health policies aimed at promoting information regarding and preventing, treating, and controlling HSV-2 infection in Brazilian Indigenous populations.

Mimics of Monkeypox: Considerations for the emergency medicine clinician

INTRODUCTION

Mpox, formerly known as monkeypox, is a public health emergency most commonly presenting with a painful rash and several systemic findings. However, there are several conditions that may mimic its presentation.

OBJECTIVE

This narrative review provides a focused overview of mpox mimics for emergency clinicians.

DISCUSSION

Mpox is a global health emergency. The disease is primarily spread through contact, followed by the development of a centrifugally-spread rash that evolves from macules to papules to vesicles to pustules. This is often associated with lymphadenopathy and fever. As the rash is one of the most common presenting signs of the infection, patients mpox may present to the emergency department (ED) for further evaluation. There are a variety of mimics of mpox, including smallpox, varicella, primary and secondary syphilis, acute retroviral syndrome, and genital herpes simplex virus.

CONCLUSION

Knowledge of mpox and its mimics is vital for emergency clinicians to differentiate these conditions and ensure appropriate diagnosis and management.

Epidemiology of herpes simplex virus type 2 in the Middle East and North Africa: Systematic review, meta-analyses, and meta-regressions

BACKGROUND

Herpes simplex virus type 2 (HSV-2) infection is a prevalent, sexually transmitted infection with poorly characterized prevalence in the Middle East and North Africa (MENA) region. This study characterized HSV-2 epidemiology in MENA.

METHODS

The systematic review was guided by the Cochrane Collaboration Handbook and findings were reported following PRISMA guidelines. Random-effects meta-analyses and meta-regressions were performed to estimate pooled mean outcome measures and to assess predictors of HSV-2 antibody prevalence (seroprevalence), trends in seroprevalence, and between-study heterogeneity.

FINDINGS

61 overall (133 stratified) HSV-2 seroprevalence measures and two overall (4 stratified) proportion measures of HSV-2 detection in laboratory-confirmed genital herpes were extracted from 37 relevant publications. Pooled mean seroprevalence was 5.1% (95% CI: 3.6-6.8%) among general populations, 13.3% (95% CI: 8.6-18.7%) among intermediate-risk populations, 20.6% (95% CI: 5.3-42.3%) among female sex workers, and 18.3% (95% CI: 3.9-39.4%) among male sex workers. Compared to Fertile Crescent countries, seroprevalence was 3.39-fold (95% CI: 1.86-6.20) and 3.90-fold (95% CI: 1.78-8.57) higher in Maghreb and Horn of Africa countries, respectively. Compared to studies published before 2010, seroprevalence was 1.73-fold (95% CI: 1.00-2.99) higher in studies published after 2015. Pooled mean proportion of HSV-2 detection in genital herpes was 73.8% (95% CI: 42.2-95.9%).

CONCLUSION

MENA has a lower HSV-2 seroprevalence than other world regions. Yet, 1 in 20 adults is chronically infected, despite conservative prevailing sexual norms. Seroprevalence may also be increasing, unlike other world regions. Findings support the need for expansion of surveillance and monitoring of HSV-2 infection in MENA. This article is protected by copyright. All rights reserved.

COVID-19 infection and vaccines: potential triggers of Herpesviridae reactivation

Since the onset of the COVID-19 outbreak, numerous articles have highlighted a possible link between COVID-19 vaccination or infection and Herpesviridae co-infection or reactivation. The authors conducted an exhaustive literature review on this topic, the results of which are presented individually for each member of the Herpesviridae family: Herpes Simplex Virus (HSV) types-1 (HSV-1) and 2 (HSV-2); Varicella-Zoster Virus (VZV); Epstein-Barr Virus (EBV); Cytomegalovirus (CMV); HHV-6; HHV-7; and HHV-8. These human herpesviruses can serve as prognostic markers for the COVID-19 infection and may even underlie some of the clinical manifestations initially attributed to SARS-CoV-2. In addition to SARS-CoV-2 infection, all corresponding vaccines approved to date in Europe appear capable of inducing herpesvirus reactivation. It is important to consider all viruses of the Herpesviridae family when managing patients infected with or recently vaccinated against COVID-19.

Epidemiology of herpes simplex virus type 1 and genital herpes in Australia and New Zealand: systematic review, meta-analyses and meta-regressions

Herpes simplex virus type 1 (HSV-1) infection is a lifelong infection that is acquired primarily orally and during childhood. We aimed to characterise HSV-1 epidemiology in Australia and New Zealand. HSV-1-related data as recent as 6 December 2021 were systematically reviewed, synthesised and reported, following PRISMA guidelines. Pooled mean seroprevalence and proportions of HSV-1 detection in genital ulcer disease (GUD) and in genital herpes were calculated using random-effects meta-analyses. Meta-regressions were also conducted. HSV-1 measures were retrieved from 21 eligible publications. Extracted HSV-1 measures included 13 overall seroprevalence measures (27 stratified) in Australia, four overall proportions of HSV-1 detection in clinically diagnosed GUD (four stratified) in Australia, and ten overall proportions of HSV-1 detection in laboratory-confirmed genital herpes (26 stratified) in Australia and New Zealand. Pooled mean seroprevalence among healthy adults in Australia was 84.8% (95% confidence interval (CI) 74.3-93.1%). Pooled mean seroprevalence was 70.2% (95% CI 47.4-88.7%) among individuals <35 years of age and 86.9% (95% CI 79.3-93.0%) among individuals ≥35 years. Seroprevalence increased by 1.05-fold (95% CI 1.01-1.10) per year. Pooled mean proportion of HSV-1 detection in GUD was 8.2% (95% CI 0.4-22.9%). Pooled mean proportion of HSV-1 detection in genital herpes was 30.5% (95% CI 23.3-38.3%), and was highest in young individuals. Proportion of HSV-1 detection in genital herpes increased by 1.04-fold (95% CI 1.00-1.08) per year. Included studies showed heterogeneity, but 30% of the heterogeneity in seroprevalence and 42% of the heterogeneity in proportion of HSV-1 detection in genital herpes were explained in terms of epidemiological factors. HSV-1 seroprevalence is higher in Australia than in other Western countries. HSV-1 epidemiology in Australia and New Zealand appears to be transitioning towards less oral acquisition in childhood, but more genital acquisition among youth.

HSV Replication: Triggering and Repressing STING Functionality

Herpes simplex virus (HSV) has persisted within human populations due to its ability to establish both lytic and latent infection. Given this, human hosts have evolved numerous immune responses to protect against HSV infection. Critical in this defense against HSV, the host protein stimulator of interferon genes (STING) functions as a mediator of the antiviral response by inducing interferon (IFN) as well as IFN-stimulated genes. Emerging evidence suggests that during HSV infection, dsDNA derived from either the virus or the host itself ultimately activates STING signaling. While a complex regulatory circuit is in operation, HSV has evolved several mechanisms to neutralize the STING-mediated antiviral response. Within this review, we highlight recent progress involving HSV interactions with the STING pathway, with a focus on how STING influences HSV replication and pathogenesis.

Manipulation of Host Cell Death Pathways by Herpes Simplex Virus

Herpes simplex virus (HSV)-1 and HSV-2 are ubiquitous human pathogens that infect keratinized epithelial surfaces and establish lifelong latent infection in sensory neurons of the peripheral nervous system. HSV-1 causes oral cold sores, and HSV-2 causes genital lesions characterized by recurrence at the site of the initial infection. In multicellular organisms, cell death plays a pivotal role in host defense by eliminating pathogen-infected cells. Apoptosis and necrosis are readily distinguished types of cell death. Apoptosis, the main form of programmed cell death, depends on the activity of certain caspases, a family of cysteine proteases. Necroptosis, a regulated form of necrosis that is unleashed when caspase activity is compromised, requires the activation of receptor-interacting protein (RIP) kinase 3 (RIPK3) through its interaction with other RIP homotypic interaction motif (RHIM)-containing proteins such as RIPK1. To ensure lifelong infection in the host, HSV carries out sophisticated molecular strategies to evade host cell death responses during viral infection. HSV-1 is a well-characterized pathogen that encodes potent viral inhibitors that modulate both caspase activation in the apoptosis pathway and RIPK3 activation in the necroptosis pathway in a dramatic, species-specific fashion. The viral UL39-encoded viral protein ICP6, the large subunit of the virus-encoded ribonucleotide reductase, functions as a suppressor of both caspase-8 and RHIM-dependent RIPK3 activities in the natural human host. In contrast, ICP6 RHIM-mediated recruitment of RIPK3 in the nonnatural mouse host drives the direct activation of necroptosis. This chapter provides an overview of the current state of the knowledge on molecular interactions between HSV-1 viral proteins and host cell death pathways and highlights how HSV-1 manipulates cell death signals for the benefit of viral propagation.

Epidemiology of herpes simplex virus type 2 in Europe: systematic review, meta-analyses, and meta-regressions

Background

Herpes simplex virus type 2 (HSV-2) infection is a globally prevalent, life-long, sexually transmitted infection. This study characterized HSV-2 seroprevalence in Europe for various at-risk populations and proportions of HSV-2 detection in genital ulcer disease (GUD) and in genital herpes. Data on neonatal herpes and HSV-2's contribution to HIV transmission were also reviewed.

Methods

Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2 related findings. The search was conducted in PubMed and Embase databases up to February 20, 2022. Any publication reporting data on the outcome measures was included. Meta-analyses and meta-regressions were conducted.

Findings

211 relevant reports were identified, including 12 overall incidence measures, 294 overall (813 stratified by factors such as age and sex) seroprevalence measures, 13 overall (15 stratified by sex) proportions of HSV-2 detection in clinically diagnosed GUD, and 70 overall (183 stratified by factors such as age and sex) proportions of HSV-2 detection in laboratory-confirmed genital herpes. Pooled mean seroprevalence was 12.4% (95% CI: 11.5-13.3%) among general populations, 27.8% (95% CI: 17.5-39.4%) among men who have sex with men, 46.0% (95% CI: 40.1-51.8%) among people living with HIV and people in HIV discordant couples, and 63.2% (95% CI: 55.5-70.6%) among female sex workers. Most measures showed heterogeneity in HSV-2 seroprevalence. The pooled mean seroprevalence among general populations increased with age and was 0.65-fold (95% CI: 0.58-0.74) lower in men than women. Seroprevalence decreased by 1% per calendar year. Pooled mean proportions of HSV-2 detection in GUD and in genital herpes were 22.0% (95% CI: 15.3-29.6%) and 66.0% (95% CI: 62.9-69.1%), respectively. HSV-2 detection in genital herpes cases was 1.21-fold (95% CI: 1.10-1.32) higher in men compared to women and decreased by 1% per calendar year. Incidence of neonatal herpes indicated an increasing trend.

Interpretation

Although seroprevalence is declining, a significant proportion of Europe's population is infected with HSV-2. HSV-2 accounts for approximately one-fifth of GUD cases and two-thirds of genital herpes cases. Findings support the need to invest in HSV-2 vaccine development, and sexual and reproductive health services.

Funding

Qatar National Research Fund [NPRP 9-040-3-008] and pilot funding from the Biomedical Research Program at Weill Cornell Medicine in Qatar supported this study.

Pharmacokinetics and Safety Study of HN0037, a Novel Anti-Human Herpes Simplex Virus Inhibitor, in Healthy Volunteers

HN0037 is a helicase-primase inhibitor developed to treat herpes simplex virus (HSV) infection. This study evaluated the safety, tolerability, and pharmacokinetics of HN0037, following oral administration in healthy volunteers. This double-blind, placebo-controlled, phase 1 study comprised two parts. In part 1, a single escalating dose of 10, 30, 60, 120, 200, 300, and 400 mg was assessed, and the food effect was evaluated in the 200-mg cohort. In part 2, a multiple dose evaluation involving 30 and 100 mg once a day was conducted for 14 days. Following single oral doses, the systemic exposure of HN0037 increased in a proportional manner over the lower dose range (10-120 mg) and in a subproportional manner over the higher dose range (200-400 mg). Following multiple oral doses, significant drug accumulation of systemic exposure was found at steady state, and the half-life ranged 50.4-61.0 h. The food effect study results indicated that a high-fat meal had a marginal impact on HN0037's pharmacokinetics. No differences were observed in the incidence of adverse events between HN0037 and placebo groups in either study. These results demonstrate that HN0037 is safe and well-tolerated, supporting further clinical development.

Identification of an anti-herpetic compound isolated from Pistacia vera L. male floral buds

Due to the numerous side effects of conventional drugs against herpetic infections and the growing phenomenon of resistance, the researchers turned to natural compounds as a source of new drugs because they are less toxic than the synthetic molecules. This study aimed to analyse the activity of Pistacia vera L. male floral bud extracts, against the replication of herpes simplex virus type 2, as well as to investigate their mode of action, isolate, and identify the active compound. Cell viability and anti-herpes virus activity were performed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and the plaque reduction assay, respectively. Three extracts (ethanolic, aqueous and polysaccharide extracts) were tested, only aqueous and polysaccharide extracts had anti-herpetic activity with a selectivity index of 29.12 and 20.25, respectively. Investigation about the mechanism of action indicated that the two active extracts inhibited the virus replication by direct contact with virucidal selectivity indexes of 39.15 and 32.09, respectively. An active compound was isolated from the aqueous extract using TLC bio-guided assay: it was identified as gallic acid by high-performance liquid chromatography-diode array detection coupled with electrospray ionization mass spectrometry (HPLC-DAD-ESI-MSn). The antiviral activity of Pistacia vera L. has been previously shown. The selectivity index of gallic acid is much lower than that of the active extract from which it has been isolated. Therefore, we can consider the aqueous extract prepared from Pistacia vera L. male floral buds as a promising natural product for treating herpetic diseases.

Treatment of Herpes Simplex Virus Type 2 Meningitis: A Survey Among Infectious Diseases Specialists in France, Sweden, Australia, and Denmark

Background

We aimed to describe attitudes toward treatment of herpes simplex virus type 2 (HSV-2) meningitis and prioritize future trials.

Methods

This was a self-administered online survey of HSV-2 meningitis treatment among infectious diseases (ID) specialists in France, Sweden, Australia, and Denmark.

Results

A total of 223 ID specialists (45% female) from France (36%), Denmark (24%), Sweden (21%), and Australia (19%) participated in the survey, primarily from university hospitals (64%). The estimated overall response rate was 11% and ranged from 6% (Australia) to 64% (Denmark). Intravenous (IV) acyclovir followed by oral valacyclovir was the favored treatment in 110 of 179 (61%), whereas monotherapy with either IV acyclovir or oral valacyclovir was used by 35 of 179 (20%) and 34 of 179 (19%), respectively. The median total duration was reported to be 7 days (interquartile range, 7-10 days) regardless of antiviral regimen. Immunocompromise influenced decisions on antiviral treatment in 110 of 189 (58%) of respondents, mainly by prolonged total duration of treatment (36/110 [33%]), prolonged IV administration (31/110 [28%]), and mandatory antiviral treatment (25/110 [23%]). Treatment with acyclovir/valacyclovir versus placebo and comparison of acyclovir versus valacyclovir were assigned the highest prioritization scores for future randomized controlled trials on HSV-2 meningitis.

Conclusions

Perceptions of indications for as well as type and duration of antiviral treatment varied substantially among ID specialists.

Herpes simplex virus type 2 inhibits TNF-α-induced NF-κB activation through viral protein ICP22-mediated interaction with p65

Herpes simplex virus type 2 (HSV-2) is a prevalent human pathogen and the main cause of genital herpes. After initial infection, HSV-2 can establish lifelong latency within dorsal root ganglia by evading the innate immunity of the host. NF-κB has a crucial role in regulating cell proliferation, inflammation, apoptosis, and immune responses. It is known that inhibition of NF-κB activation by a virus could facilitate it to establish infection in the host. In the current study, we found that HSV-2 inhibited TNF-α-induced activation of NF-κB-responsive promoter in a dose-dependent manner, while UV-inactivated HSV-2 did not have such capability. We further identified the immediate early protein ICP22 of HSV-2 as a vital viral element in inhibiting the activation of NF-κB-responsive promoter. The role of ICP22 was confirmed in human cervical cell line HeLa and primary cervical fibroblasts in the context of HSV-2 infection, showing that ICP22 deficient HSV-2 largely lost the capability in suppressing NF-κB activation. HSV-2 ICP22 was further shown to suppress the activity of TNF receptor-associated factor 2 (TRAF2)-, IκB kinase α (IKK α)-, IKK β-, IKK γ-, or p65-induced activation of NF-κB-responsive promoter. Mechanistically, HSV-2 ICP22 inhibited the phosphorylation and nuclear translocation of p65 by directly interacting with p65, resulting in the blockade of NF-κB activation. Furthermore, ICP22 from several alpha-herpesviruses could also inhibit NF-κB activation, suggesting the significance of ICP22 in herpesvirus immune evasion. Findings in this study highlight the importance of ICP22 in inhibiting NF-κB activation, revealing a novel mechanism by which HSV-2 evades the host antiviral responses.

The association between Herpes simplex virus type 2 and asthma: A cross-sectional study from National Health and Nutrition Examination Survey 1999–2016

Background

The association between Herpes simplex virus type 2 (HSV-2) infection, a common infectious disease that increases the incidence of multisystem diseases, and asthma was less well studied. The aim of this study was to investigate the association between HSV-2 infection and the prevalence of asthma.

Materials and methods

We used data from National Health and Nutrition Examination Survey (NHANES) 1999–2016 for analysis. The study population included was limited to those aged 20–45 years and contained complete information on HSV-2 infection and asthma. We calculated the prevalence of HSV-2, asthma, and HSV-2 combined with asthma separately. The association between HSV-2 infection and asthma was analyzed using multiple logistic regression. We also performed stratified analyses to reduce bias and to find sensitive cohorts.

Results

The prevalence of HSV-2 infection was decreasing with change in time period (P for trend < 0.01), but the prevalence of asthma was increasing (P for trend < 0.01). The prevalence of HSV-2 infection was higher in those with asthma than in non-asthma participants. A positive association was found between HSV-2 infection and asthma [odds ratio (OR) = 1.15, 95% CI: 1.04–1.27]. Subgroup analysis showed that this positive association was more pronounced in participants who were male, White, 30 years ≤ age ≤ 40 years, body mass index (BMI) ≤ 28 kg/m², 1.39 ≤ ratio of family income to poverty (PIR) < 3.49 and smokers.

Conclusion

There was a positive association between HSV-2 infection and asthma, and participants who were male, White race, 30 years ≤ age < 40 years, BMI ≥ 28 kg/m², 1.39 ≤ PIR < 3.49, and smokers should receive more attention.

CCL28 Enhances HSV-2 gB-Specific Th1-Polarized Immune Responses against Lethal Vaginal Challenge in Mice

Plasmid DNA (pDNA) represents a promising “genetic vaccine platform” capable of overcoming major histocompatibility complex barriers. We previously demonstrated that low-to-moderate doses of mucosae-associated epithelial chemokine (MEC or CCL28) as an immunomodulatory adjuvant can trigger effective and long-lasting systemic and mucosal HSV-2 gD-specific immune responses, whereas mice immunized with gD in combination with high-dose CCL28 showed toxicity and lost their immunoprotective effects after lethal HSV-2 challenge. The exact causes underlying high-dose, CCL28-induced lesions remain unknown. In an intramuscularly immunized mouse model, we investigated the immune-enhancement mechanisms of low-dose CCL28 as a molecular adjuvant combined with the relatively weak immunogen HSV-2 gB. Compared with the plasmid gB antigen group, we found that a low-dose of plasmid CCL28 (pCCL28) codelivered with pgB induced increased levels of gB-specific serum IgG and vaginal fluid IgA, serum neutralizing antibodies (NAb), Th1-polarized IgG2a, and cytokine IL-2 (>5-fold). Furthermore, low-dose pCCL28 codelivery with pgB enhanced CCL28/CCR10-axis responsive CCR10− plus CCR10+ B-cell (~1.2-fold) and DC pools (~4-fold) in the spleen, CCR10− plus CCR10+ T-cell pools (~2-fold) in mesenteric lymph nodes (MLNs), and the levels of IgA-ASCs in colorectal mucosal tissues, leading to an improved protective effect against a lethal dose of HSV-2 challenge. Findings in this study provide a basis for the development of CCL28-adjuvant vaccines against viral mucosal infections.

Role of Microglia in Herpesvirus-Related Neuroinflammation and Neurodegeneration

Neuroinflammation is defined as an inflammatory state within the central nervous system (CNS). Microglia conprise the resident tissue macrophages of the neuronal tissue. Upon viral infection of the CNS, microglia become activated and start to produce inflammatory mediators important for clearance of the virus, but an excessive neuroinflammation can harm nearby neuronal cells. Herpesviruses express several molecular mechanisms, which can modulate apoptosis of infected neurons, astrocytes and microglia but also divert immune response initiated by the infected cells. In this review we also describe the link between virus-related neuroinflammation, and development of neurodegenerative diseases.

Oleanolic Acid Derivative AXX-18 Exerts Antiviral Activity by Inhibiting the Expression of HSV-1 Viral Genes UL8 and UL52

Two-thirds of the world’s population is infected with HSV-1, which is closely associated with many diseases, such as Gingival stomatitis and viral encephalitis. However, the drugs that are currently clinically effective in treating HSV-1 are Acyclovir (ACV), Ganciclovir, and Valacyclovir. Due to the widespread use of ACV, the number of drug-resistant strains of ACV is increasing, so searching for new anti-HSV-1 drugs is urgent. The oleanolic-acid derivative AXX-18 showed a CC₅₀ value of 44.69 μM for toxicity to HaCaT cells and an EC₅₀ value of 1.47 μM for anti-HSV-1/F. In addition, AXX-18 showed significant inhibition of ACV-resistant strains 153, 106, and Blue, and the anti-HSV-1 activity of AXX-18 was higher than that of oleanolic acid. The mechanism of action of AXX-18 was found to be similar to that of oleanolic acid, except that AXX-18 could act on both the UL8 and UL52 proteins of the uncoupling helicase-primase enzyme, whereas oleanolic acid could only act on the UL8 protein. We have elucidated the antiviral mechanism of AXX-18 in detail and, finally, found that AXX-18 significantly inhibited the formation of skin herpes. In conclusion, we have explored the anti-HSV-1 activity of AXX-18 in vitro and in vivo as well as identification of its potential target proteins, which will provide a theoretical basis for the development of subsequent anti-HSV-1 drugs.

Impact of primary and recurrent genital herpes on the quality of life of young people and adults: a mixed methods systematic review

OBJECTIVE

This review sought to identify the experiences of persons living with genital herpes and what interventions improve the health-related quality of life of young people and adults with primary or recurrent genital herpes.

INTRODUCTION

Genital herpes is commonly associated with psychosocial challenges. However, a growing body of evidence suggests that its impact can be ameliorated through pharmacological and psychosocial interventions.

INCLUSION CRITERIA

This review considered English- and German-language studies of community-dwelling males and females, of any ethnicity and geographical location, aged 15 years and older, who had primary or recurrent genital herpes. The quantitative component of the review included studies that reported on the virus' impact on patients' health-related quality of life and/or the efficacy of interventions in improving their health-related quality of life. Studies compared antiviral suppression therapies and psychological interventions with usual care or placebo, or against one another. The qualitative component of the review included studies that investigated the perceptions and experiences of young people and adults with genital herpes.

METHODS

Eleven databases were searched from January 1980 to March 2020. The JBI approach to mixed methods systematic reviews was followed at each stage of the review, and a convergent segregated approach to synthesis and integration was adopted.

RESULTS

A total of 31 publications covering 30 studies were deemed suitable for inclusion. Studies encompassed quantitative (n = 27, across 28 publications), qualitative (n = 1), and mixed methods (n = 2) designs. Critical appraisal scores were variable, particularly among the randomized controlled trials and the analytical cross-sectional studies. All studies were included regardless of methodological quality. The quantitative components identified that depression, illness concern, stress, anxiety, isolation, stigma, and a lowering of self-esteem, self-concept, self-confidence, and health-related quality of life may be experienced by both those newly diagnosed with genital herpes and those with recurrences. It was also identified that genital herpes can have an adverse effect on work or school, sexual relationships, and relationships with friends and family. Depression was found to significantly decrease after self-hypnosis and certain psychosocial interventions. Anxiety significantly decreased following pharmacological treatment, psychosocial interventions, and hypnosis. Psychosocial interventions significantly improved mood, and a self-help module with counseling significantly improved participants' satisfaction with intimate relationships and their self-esteem. Pharmacological treatment significantly improved health-related quality of life; however, there were no significant differences between different active treatment regimens. The qualitative component of the review led to the identification of two synthesized findings: "Disclosure of a diagnosis of genital herpes poses a dilemma for people who have the virus" and "A diagnosis of genital herpes has a significant emotional impact for the individual."Integration of quantitative and qualitative evidence revealed a consensus that a diagnosis of genital herpes has a significant emotional impact for individuals and that disclosure is stressful, affects relationships, and affects health-related quality of life; however, there is a lack of consensus regarding efficacy of different interventions.

CONCLUSIONS

Genital herpes can lead to extreme emotional, social, relational, and sexual distress, but there is insufficient knowledge concerning which interventions best improve health-related quality of life. More high-quality research is required.

Epidemiology of Herpes Simplex Virus Type 2 in Canada, Australia, and New Zealand: Systematic Review, Meta-Analyses, and Meta-Regressions

BACKGROUND

This study characterized the epidemiology of herpes simplex virus type 2 (HSV-2) infection in Canada, Australia, and New Zealand.

METHODS

Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2-related data up to January 21, 2021. Meta-analyses and meta-regressions were performed.

RESULTS

In Canada, pooled mean seroprevalence was 10.0% (95% confidence interval [CI], 7.8-12.4%) among general populations, 44.5% (95% CI, 20.0-70.5%) among sexually transmitted infection clinic attendees and symptomatic populations, and 60.7% (95% CI, 49.8-71.1%) among human immunodeficiency virus (HIV)-positive individuals and individuals in HIV-discordant couples. In Australia and New Zealand, combined, pooled mean seroprevalence was 15.4% (95% CI, 9.6-22.2%) among general populations, 27.8% (95% CI, 12.0-47.2%) among men who have sex with men, and 37.2% (95% CI, 23.7-51.8%) among sexually transmitted infection clinic attendees and symptomatic populations. Men had 0.64-fold (95% CI, 0.47-0.86) lower seroprevalence compared with women. No evidence was found for a decline in seroprevalence over time. Pooled mean proportion of HSV-2 isolation in laboratory-confirmed genital herpes was 62.1% (95% CI, 53.8-70.1%) in Canada and 71.9% (95% CI, 64.2-78.9%) in Australia and New Zealand. Proportion of HSV-2 isolation in genital herpes declined by 0.98-fold (95% CI, 0.97-0.99) per year. Pooled mean proportion of HSV-2 isolation in genital ulcer disease was 17.4% (95% CI, 4.0-37.1%) in these countries.

CONCLUSIONS

Over 10% of adults in these countries are infected, with no evidence for declining seroprevalence, unlike other global regions. Over 60% of genital herpes cases are caused by HSV-2 in these countries, yet HSV-2's role is declining by 2% per year.

Promising Role of Emodin as Therapeutics to Against Viral Infections

Emodin is an anthraquinone derivative that is widely present in natural plants and has a wide spectrum of pharmacological effects, such as antibacterial, anti-inflammatory, anti-fibrotic and anticancer and so on. Through reviewing studies on antiviral effect of emodin in the past decades, we found that emodin exhibits ability of inhibiting the infection and replication of more than 10 viruses in vitro and in vivo, including herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2), human cytomegalovirus (HCMV), Epstein-Barr virus (EBV), coxsackievirus B (CVB), hepatitis B virus (HBV), influenza A virus (IAV), SARS-CoV, viral haemorrhagic septicaemia rhabdovirus (VHSV), enterovirus 71 (EV71), dengue virus serotype 2 (DENV-2) and Zika virus (ZIKV). Therefore, this review aims to summarize the antiviral effect of emodin, in order to provide reference and hopes to support the further investigations.

Factors associated with transmasculine adults recently engaging in sexual behavior with partners of unknown STI and HIV status

The sexual partnerships of transmasculine (TM) adults-those assigned female at birth who identify as transgender men or a masculine spectrum gender identity-and characteristics associated with STI/HIV risk behavior remains understudied. Participants in the current study were TM adults (n = 141) receiving care at a community health center in Boston, Massachusetts between March 2015 and September 2016. Using generalized estimating equations, we examined individual- and partnership-level factors associated with TM adults' odds of engaging in sexual behavior with a sexual partner of unknown STI/HIV status in the past 12 months. TM adults with casual sexual partnerships (vs. monogamous partnerships) and those in partnerships with cisgender men, other TM individuals, or transfeminine partners (vs. cisgender women) had statistically significantly higher odds of engaging in sexual behavior with a partner of unknown STI/HIV status in the past 12 months. Findings may inform future efforts to improve sexual health communication and STI/HIV disclosure between TM adults and their sexual partners.

An mRNA vaccine to prevent genital herpes

The rapid development of two nucleoside-modified mRNA vaccines that are safe and highly effective against coronavirus disease 2019 has transformed the vaccine field. The mRNA technology has the advantage of accelerated immunogen discovery, induction of robust immune responses, and rapid scale up of manufacturing. Efforts to develop genital herpes vaccines have been ongoing for 8 decades without success. The advent of mRNA technology has the potential to change that narrative. Developing a genital herpes vaccine is a high public health priority. A prophylactic genital herpes vaccine should prevent HSV-1 and HSV-2 genital lesions and infection of dorsal root ganglia, the site of latency. Vaccine immunity should be durable for decades, perhaps with the assistance of booster doses. While these goals have been elusive, new efforts with nucleoside-modified mRNA-lipid nanoparticle vaccines show great promise. We review past approaches to vaccine development that were unsuccessful or partially successful in large phase 3 trials, and describe lessons learned from these trials. We discuss our trivalent mRNA-lipid nanoparticle approach for a prophylactic genital herpes vaccine and the ability of the vaccine to induce higher titers of neutralizing antibodies and more durable CD4+ T follicular helper cell and memory B cell responses than protein-adjuvanted vaccines.

Two-Metal Ion-Dependent Enzymes as Potential Antiviral Targets in Human Herpesviruses

The majority of drug discovery efforts against herpesviruses have focused on nucleoside analogs that target viral DNA polymerases, agents that are associated with dose-limiting toxicity and/or a narrow spectrum of activity. We are pursuing a strategy based on targeting two-metal ion-dependent (TMID) viral enzymes. This family of enzymes consists of structurally related proteins that share common active sites containing conserved carboxylates predicted to coordinate divalent cations essential for catalysis. Compounds that target TMID enzymes, such as HIV integrase and influenza endoribonuclease, have been successfully developed for clinical use. HIV integrase inhibitors have been reported to inhibit replication of herpes simplex virus (HSV) and other herpesviruses; however, the molecular targets of their antiviral activities have not been identified. We employed a candidate-based approach utilizing several two-metal-directed chemotypes and the potential viral TMID enzymatic targets in an effort to correlate target-based activity with antiviral potency. The panel of compounds tested included integrase inhibitors, the anti-influenza agent baloxavir, three natural products previously shown to exhibit anti-HSV activity, and two 8-hydroxyquinolines (8-HQs), AK-157 and AK-166, from our in-house program. The integrase inhibitors exhibited weak overall anti-HSV-1 activity, while the 8-HQs were shown to inhibit both HSV-1 and cytomegalovirus (CMV). Target-based analysis demonstrated that none of the antiviral compounds acted by inhibiting ICP8, contradicting previous reports. On the other hand, baloxavir inhibited the proofreading exonuclease of HSV polymerase, while AK-157 and AK-166 inhibited the alkaline exonuclease UL12. In addition, AK-157 also inhibited the catalytic activity of the HSV polymerase, which provides an opportunity to potentially develop dual-targeting agents against herpesviruses. IMPORTANCE Human herpesviruses (HHVs) establish lifelong latent infections, which undergo periodic reactivation and remain a major cause of morbidity and mortality, especially in immunocompromised individuals. Currently, HHV infections are treated primarily with agents that target viral DNA polymerase, including nucleoside analogs; however, long-term treatment can be complicated by the development of drug resistance. New therapies with novel modes of action would be important not only for the treatment of resistant viruses but also for use in combination therapy to reduce dose-limiting toxicities and potentially eliminate infection. Since many essential HHV proteins are well conserved, inhibitors of novel targets would ideally exhibit broad-spectrum activity against multiple HHVs.

Galectins as potential therapeutic targets in STIs in the female genital tract

Every day, more than one million people worldwide acquire a sexually transmitted infection (STI). This public health problem has a direct effect on women's reproductive and sexual health as STIs can cause irreversible damage to fertility and can have negative consequences associated with discrimination and social exclusion. Infection with one sexually transmitted pathogen predisposes to co-infection with others, suggesting the existence of shared pathways that serve as molecular links between these diseases. Galectins, a family of β-galactoside-binding proteins, have emerged as endogenous mediators that facilitate cell-surface binding, internalization and cell invasion of many sexually transmitted pathogens, including Chlamydia trachomatis, Neisseria gonorrhoeae, Trichomonas vaginalis, Candida albicans, HIV and herpes simplex virus. The ability of certain galectins to dimerize or form multimeric complexes confers the capacity to interact simultaneously with glycosylated ligands on both the pathogen and the cervico-vaginal tissue on these proteins. Galectins can act as a bridge by engaging glycans from the pathogen surface and glycosylated receptors from host cells, which is a mechanism that has been shown to be shared by several sexually transmitted pathogens. In the case of viruses and obligate intracellular bacteria, binding to the cell surface promotes pathogen internalization and cell invasion. Inflammatory responses that occur in cervico-vaginal tissue might trigger secretion of galectins, which in turn control the establishment, evolution and severity of STIs. Thus, galectin-targeted therapies could potentially prevent or decrease STIs caused by a diverse array of pathogenic microorganisms; furthermore, anti-galectin agents might reduce treatment costs of STIs and reach the most vulnerable populations.

Healthcare resource utilisation pattern and costs associated with herpes simplex virus diagnosis and management: a systematic review

OBJECTIVES

Little is known about the economic burden of herpes simplex virus (HSV) across countries. This article aims to summarise existing evidence on estimates of costs and healthcare resource utilisation associated with genital and neonatal HSV infection.

DESIGN

Systematic literature review.

DATA SOURCES

Seven databases were searched from inception to 31 August 2020. A focused search was performed to supplement the results.

ELIGIBILITY CRITERIA

Studies which reported either healthcare resource utilisation or costs associated with HSV-related healthcare, including screening, diagnosis and treatment of genital HSV infection and neonatal herpes prevention and treatment.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers extracted data and assessed the risk of bias using the Larg and Moss's checklist. All data were summarised narratively.

RESULTS

Out of 11 443 articles, 38 were included. Most studies (35/38, 94.6%) were conducted in high-income countries, primarily the United States, and were more often related to the prevention or management of neonatal herpes (n=21) than HSV genital ulcer disease (n=17). Most analyses were conducted before 2010. There was substantial heterogeneity in the reporting of HSV-related healthcare resource utilisation, with 74%-93% individuals who sought care for HSV, 11.6%-68.4% individuals who received care, while neonates with herpes required a median of 6-34 hospitalisation days. The costs reported were similarly heterogeneous, with wide variation in methodology, assumptions and outcome measures between studies. Cost for screening ranged from US$7-100, treatment ranged from US$0.53-35 for an episodic therapy, US$240-2580 yearly for suppressive therapy, while hospitalisation for neonatal care ranged from US$5321-32 683.

CONCLUSIONS

A paucity of evidence exists on healthcare resource utilisation and costs associated with HSV infection, especially among low-income and middle-income countries. Future research is needed on costs and healthcare utilisation patterns to improve overall understanding of the global economic burden of HSV.