Herpes simplex virus type 1 epidemiology in Latin America and the Caribbean: Systematic review and meta-analytics

Estimated global and regional incidence and prevalence of herpes simplex virus infections and genital ulcer disease in 2020: mathematical modelling analyses

OBJECTIVES

Genital herpes simplex virus (HSV) type 1 and 2 infections are lifelong and can cause symptomatic genital ulcer disease (GUD). HSV-2 almost always causes sexually transmitted genital infection, while HSV-1 mainly causes oral infection but can be sexually transmitted to cause genital infection. This study estimated genital infection with both HSV types and associated GUD globally in 2020, breaking down the data by WHO region and sex for females and males.

METHODS

A calibrated mathematical model was employed to generate estimates for the incidence and prevalence of HSV-2 infection, genital HSV-1 infection, and GUD caused by both HSV types. Estimates for non-genital infections caused by HSV-1 were also generated. Model input was derived from a comprehensive systematic review and meta-analyses of HSV prevalence data for all WHO regions.

RESULTS

Globally in 2020 there were 25.6 million (95% uncertainty interval (UI) 23.1-29.4 million) people aged 15-49 years with new HSV-2 infections, and 519.5 million (95% UI 464.3-611.3 million), or 13.3% (95% UI 11.9-15.6%), with existing (prevalent) HSV-2 infections. In addition, there were 16.8 million (95% UI 10.6-22.4 million) people aged 15-49 years with new genital HSV-1 infections and 376.2 million (95% UI 235.6-483.5 million), or 10.2% (95% UI 6.4-13.1%), with prevalent genital HSV-1 infections. The estimated number of people aged 15-49 years with at least one episode of HSV-attributable GUD in 2020 was 187.9 million (95% UI 116.0-291.8 million) for HSV-2, and 16.7 million (95% UI 9.3-25.2 million) for HSV-1, totalling 204.6 million (95% UI 132.3-306.5 million).

CONCLUSION

Genital HSV infections have a high incidence and prevalence worldwide, contributing to a significant GUD disease burden. New prevention and treatment measures, such as prophylactic and therapeutic HSV vaccines, are needed critically to control HSV infections and reduce the associated disease burden.

Epidemiology of herpes simplex virus type 1 in the United States: Systematic review, meta-analyses, and meta-regressions

This study aimed to analytically describe the epidemiology of herpes simplex virus type 1 (HSV-1) infection in the United States through a systematic review and meta-analytics. We reviewed 159 publications, identifying 190 seroprevalence measures and 43 proportions of HSV-1 detection in genital herpes. The pooled mean HSV-1 seroprevalence was 38.0% (95% CI: 30.9-45.4) among general-population children and 63.5% (95% CI: 61.3-65.7) among general-population adults. Age explained 43% of the seroprevalence variation, with rates increasing progressively with age. Seroprevalence declined by 0.99-fold (95% CI: 0.99-0.99) per year. The pooled mean proportion of HSV-1 detection in genital herpes was 15.4% (95% CI: 10.8-20.6), increasing by 1.02-fold (95% CI: 1.00-1.04) per year. Recurrent genital herpes had a 0.17-fold (95% CI: 0.09-0.32) lower proportion of HSV-1 detection compared to first-episode cases. The epidemiology of HSV-1 is shifting, marked by a decline in oral acquisition during childhood and an increase in genital acquisition during adulthood.

High silent prevalence of human herpesvirus 1 (HSV-1) infection affecting the indigenous reservation of the municipality of Dourados, Central-West Brazil

BACKGROUND

The indigenous population located in the central region of Brazil, is the second largest in terms of population size in the country. The Indigenous Reserve of Dourados has risk factors that increase the vulnerability of the indigenous population to infectious diseases, especially Human alphaherpesvirus (HSV-1), a neglected disease with high prevalence in priority populations in developing countries. The virus can also cause many more severe diseases, including widespread neonatal infections, herpetic keratitis, and herpes encephalitis, which can be fatal if left untreated. We estimated the prevalence of anti-HSV-1 antibodies and correlated it with the demographic and behavioral characteristics of the Indigenous population of the Jaguapirú and Bororó villages (Dourados, Mato Grosso do Sul (MS), Brazil).

METHODS

Our approach was cross-sectional. From March 2017 to November 2018. Using anti-HSV-1 (Gg1) IgM and anti-HSV-1 (gG1) IgG Euroimmun and the detection and quantification of HSV-1 viral load in plasma samples, through real-time PCR. The maps were constructed using QGIS and the statistical analyses using R Studio software.

RESULTS

A total of 1138 individuals (> 18 years old) were enrolled. The prevalence of anti-HSV-1 IgM and IgG were 20% and 97.5%, respectively. The prevalence of anti-HSV-1 antibodies for IgG was higher in both sexes. Anti-HSV-1 IgM antibodies were present in 17.1%, 21.2%, 12.5%, and 22% of the participants with urinary problems, genital wounds, genital warts, and urethral discharge, respectively. Real-time PCR was used for confirmatory testing; HSV-1 DNA was detected in 25.6% (54/211) of anti-HSV1 IgM-positive samples. Viral loads ranged from 5.99E + 02 to 3.36E + 13.

CONCLUSIONS

The seroprevalence of HSV-1 IgM and detection of HSV-1 DNA in the Indigenous population confirmed high silent prevalence. Furthermore, the seroprevalence of HSV-1 in the Indigenous population was higher than that reported in the general adult Brazilian population. Various socioeconomic factors, drug use, and health and sexual behaviors could contribute to the facilitation of HSV-1 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 the prevention, treatment, and control of HSV-1 infection in Brazilian Indigenous populations.

Contribution of CNS and extra-CNS infections to neurodegeneration: a narrative review

Central nervous system infections have been suggested as a possible cause for neurodegenerative diseases, particularly sporadic cases. They trigger neuroinflammation which is considered integrally involved in neurodegenerative processes. In this review, we will look at data linking a variety of viral, bacterial, fungal, and protozoan infections to Alzheimer's disease, Parkinson's disease, amyotrophic lateral sclerosis, multiple sclerosis and unspecified dementia. This narrative review aims to bring together a broad range of data currently supporting the involvement of central nervous system infections in the development of neurodegenerative diseases. The idea that no single pathogen or pathogen group is responsible for neurodegenerative diseases will be discussed. Instead, we suggest that a wide range of susceptibility factors may make individuals differentially vulnerable to different infectious pathogens and subsequent pathologies.

The profile of Oral Health Branch of Rafsanjan Cohort Study (OHBRCS) in Rafsanjan City, southeast of Iran

Oral health status can be affected by some factors including drug abuse, systemic conditions and environmental pollutants. The present study was designed to investigate the most important and prevalent dental and oral conditions in adult population of Rafsanjan with the age of 35-70 years. Dental and oral health cohort center as part of the Rafsanjan Cohort Study (RCS) included in the prospective epidemiological research studies in IrAN was established in 2015. Of 9991 subjects enrolled in the RCS, 8682 people participated in the Oral Health Branch of Rafsanjan Cohort Study (OHBRCS). The OHBRCS included 4021 men and 4661 women with the mean age of 49.94 ± 9.51. The most prevalent of oral lesion in total population was candidiasis and the least was aphthous lesion. The prevalence of candidiasis, white and red lesions, periodontal pocket, dental calculus, CAL and the mean of DMFT were higher in the male group than that of female group (p < 0.05). Candidiasis, herpes, oral cancer, white and red lesions were more prevalent in the older age groups (p < 0.05). The mean of DMFT index in total population was 21.30 and was higher among opium users, men and older age (p < 0.05). Also, the opium users had a higher rate of CAL, periodontal pocket, red and white lesions, and candidiasis but a lower rate of BOP (p < 0.05). Younger people had more decayed and filling teeth compared to other age groups, whereas older people had more missing teeth and a higher DMFT index (p < 0.001).

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.

Genital Herpes Infection: Progress and Problems

Genital herpes (GH) is a sexually transmitted infection causing recurrent, self-limited genital, buttock, and thigh ulcerations. Symptoms range from unrecognized or mild to severe with frequent recurrences. Herpes simplex viruses (HSV) type-1 or type-2 cause GH. HSV establishes latency in sacral ganglia and causes lifelong infection. Viral reactivation leads to genital ulceration or asymptomatic shedding which may lead to transmission. HSV infection during pregnancy can cause fulminant hepatitis and neonatal transmission. Severe and atypical manifestations are seen in immunocompromised people. Guanosine analogs treat symptoms and prevent recurrences, shedding, and transmission. Novel preventive and therapeutic strategies are in development.

Low Prevalence of HSV-1 and Helicobacter pylori in HNSCC and Chronic Tonsillitis Patients Compared to Healthy Individuals

Recent studies identified viral and bacterial factors, including HSV-1 and H. pylori, as possible factors associated with diseases such as chronic tonsillitis and cancers, including head and neck squamous cell carcinoma (HNSCC). We assessed the prevalence of HSV-1/2 and H. pylori in patients with HNSCC, chronic tonsillitis, and healthy individuals using PCR after DNA isolation. Associations were sought between the presence of HSV-1, H. pylori, and clinicopathological and demographic characteristics and stimulant use. HSV-1 and H. pylori were most frequently identified in controls (HSV-1: 12.5% and H. pylori: 6.3%). There were 7 (7.8%) and 8 (8.6%) patients with positive HSV-1 in HNSCC and chronic tonsillitis patients, respectively, while the prevalence of H. pylori was 0/90 (0%) and 3/93 (3.2%), respectively. More cases of HSV-1 were observed in older individuals in the control group. All positive HSV-1 cases in the HNSCC group were associated with advanced tumor stage (T3/T4). The prevalence of HSV-1 and H. pylori was highest in the controls compared to HNSCC and chronic tonsillitis patients, which indicates that the pathogens were not risk factors. However, since all positive HSV-1 cases in the HNSCC group were observed only in patients with advanced tumor stage, we suggested a possible link between HSV-1 and tumor progression. Further follow-up of the study groups is planned.

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.

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.

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.

Safety, efficacy and delivery of multiple nucleoside analogs via drug encapsulated carbon (DECON) based sustained drug release platform

Acyclovir and similar nucleoside analogs form an essential frontline treatment for various herpesvirus infections of the eye. However, these drugs have low ocular retention when delivered topically and need to be administered several times every day. We have previously demonstrated that acyclovir loaded into activated carbon can be used to significantly decrease dosage frequency in a murine model of ocular infection. In this study, we demonstrate that other nucleoside analogs such as ganciclovir, penciclovir and famciclovir have excellent loading and release profile similar to acyclovir. Similarly we also demonstrate that nucleoside analog loaded carbons termed DECON are effective at very low concentrations in treating active viral infection of human corneal epithelial cells. In this study, using a variety of techniques to evaluate corneal dryness, nerve sensitivity, intraocular pressure, corneal thickness, and somatic inflammation, we report that DECON is well tolerated after administration three times daily over the course of four weeks.

Metagenomic Next-Generation Sequencing in the Diagnosis of HHV-1 Reactivation in a Critically Ill COVID-19 Patient: A Case Report

Background: Secondary infections pose tremendous challenges in Coronavirus disease 2019 (COVID-19) treatment and are associated with higher mortality rates. Clinicians face of the challenge of diagnosing viral infections because of low sensitivity of available laboratory tests.

Case Presentation: A 66-year-old woman initially manifested fever and shortness of breath. She was diagnosed as critically ill with COVID-19 using quantitative reverse transcription PCR (RT-qPCR) and treated with antiviral therapy, ventilator and extracorporeal membrane oxygenation (ECMO). However, after the condition was relatively stabled for a few days, the patient deteriorated with fever, frequent cough, increased airway secretions, and increased exudative lesions in the lower right lung on chest X-rays, showing the possibility of a newly acquired infection, though sputum bacterial and fungal cultures and smears showed negative results. Using metagenomic next-generation sequencing (mNGS), we identified a reactivation of latent human herpes virus type 1 (HHV-1) in the respiratory tract, blood and gastrointestinal tract, resulting in a worsened clinical course in a critically ill COVID-19 patient on ECMO. Anti-HHV-1 therapy guided by these sequencing results effectively decreased HHV-1 levels, and improved the patient's clinical condition. After 49 days on ECMO and 67 days on the ventilator, the 66-year-old patient recovered and was discharged.

Conclusions: This case report demonstrates the potential value of mNGS for evidence-based treatment, and suggests that potential reactivation of latent viruses should be considered in critically ill COVID-19 patients.

Epidemiology of herpes simplex virus type 2 in Asia: A systematic review, meta-analysis, and meta-regression

Background

Herpes simplex virus type 2 (HSV-2) infection is a prevalent sexually transmitted infection worldwide. This systematic review was conducted to characterize HSV-2 epidemiology in Asia, including the World Health Organization regions of Southeast Asia and the Western Pacific.

Methods

Cochrane and PRISMA guidelines were followed to systematically review and report findings. Pooled mean seroprevalence and proportions of HSV-2 isolated in genital ulcer disease (GUD) and in genital herpes were calculated using random-effects meta-analyses. Meta-regressions were also conducted. Quality assessment was performed.

Findings

HSV-2 measures extracted from 173 publications included 15 seroconversion rates, 11 seroincidence rates, 272 overall seroprevalence measures (678 stratified), 14 proportions of HSV-2 isolation in GUD (15 stratified), and 27 proportions of HSV-2 isolation in genital herpes (36 stratified). Pooled mean seroprevalence was 12.1% (95% confidence interval (CI): 11.0-13.2%) among general populations, 23.6% (95% CI: 20.9-26.3%) among men who have sex with men and transgender people, 46.0% (95% CI: 39.2-52.9%) among HIV-positive individuals and individuals in HIV-discordant couples, and 62.2% (95% CI: 58.9-65.6%) among female sex workers. Among general populations, pooled mean seroprevalence increased gradually from 4.7% (95% CI: 3.3-6.3%) in <20-year-old individuals to 26.6% (95% CI: 19.2-34.7%) in >60-year-old individuals. Compared to women and across all populations, men had 0.60-fold (95% CI: 54.0-67.0) lower seroprevalence, that is women had 70% higher seroprevalence. Seroprevalence declined by 0.98-fold (95% CI: 0.97-0.99) per year, that is a 2% decline per year in the last three decades. Pooled mean proportions of HSV-2 isolation in GUD and in genital herpes were 48.2% (95% CI: 34.9-61.6%) and 75.9% (95% CI: 68.3-82.8%), respectively.

Interpretation

Over 1 in 10 individuals is infected with HSV-2, but seroprevalence is declining. HSV-2 accounts for half of GUD cases and three-quarters of genital herpes cases. These findings support the need for an HSV-2 vaccine and universal access to sexual and reproductive health services.

Funding

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

Herpes simplex virus type 1 in Europe: systematic review, meta-analyses and meta-regressions

Objective

To describe the epidemiology of herpes simplex virus type 1 (HSV-1) in Europe.

Methods

We systematically reviewed HSV-1 related publications, conducted various meta-analyses and meta-regressions, assessed pooled mean seroprevalence, and estimated pooled mean proportions of HSV-1 viral detection in clinically diagnosed genital ulcer disease (GUD) and in genital herpes.

Results

We extracted, from 142 relevant records, 179 overall (622 stratified) seroprevalence measures, 4 overall proportions of HSV-1 in GUD and 64 overall (162 stratified) proportions of HSV-1 in genital herpes. Pooled mean seroprevalence was 67.4% (95% CI 65.5% to 69.3%) with 32.5% (95% CI 29.4% to 35.7%) of children and 74.4% (95% CI 72.8% to 76.0%) of adults infected. Pooled seroprevalence increased steadily with age, being lowest in those aged <20 years (39.3%, 95% CI 35.9% to 42.7%) and highest in those aged >50 years (82.9%, 95% CI 78.8% to 86.6%). Pooled seroprevalence decreased yearly by 0.99-fold (95% CI 0.99 to 1.00). Pooled mean proportion of HSV-1 detection was 13.6% (95% CI 4.1% to 27.1%) in GUD, 34.1% (95% CI 31.7% to 36.5%) in genital herpes and 49.3% (95% CI 42.2% to 56.4%) in first episode genital herpes. Pooled proportion of HSV-1 detection in genital herpes increased yearly by 1.01-fold (95% CI 1.00 to 1.02), with higher detection in women (42.0%, 95% CI 37.4% to 46.7%) than men (24.1%, 95% CI 19.8% to 28.6%).

Conclusions

HSV-1 epidemiology is transitioning away from its historical pattern of oral acquisition in childhood. Every year, seroprevalence is declining by 1% and the proportion of HSV-1 in genital herpes is increasing by 1%. As many as two-thirds of children are reaching sexual debut unexposed, and at risk of HSV-1 genital acquisition in adulthood.

Bruxism and type of breathing as factors associated with oral herpes lesion in Brazilian para-athletes

AIMS

The present study investigated if recurrent manifestation of oral herpes lesions is associated with other factors and impacts the oral health-related quality of life in para-athletes.

METHODS AND RESULTS

The studied population was composed of a convenience sample of 370 Brazilian para-athletes. All included individuals answered questionnaires and were submitted to an oral examination. A self-reported questionnaire addressed demographic and oral health data, including the recurrent manifestation of oral herpes lesions. The Oral Health Impact Profile was also applied in its reduced version with 14 questions (OHIP-14). The population was categorized according to results from previous competitions into a high-performance level, medium-performance level, and regional-performance level. Chi-square or Fisher's exact tests, odds ratio calculation, logistic regression analysis, and t-tests were performed (α = 5%). Sixty (16.2%) para-athletes reported recurrent manifestations of oral herpes lesions. Para-athletes with sleep bruxism (p = .007) and awake bruxism (p = .048) had a higher chance of reporting oral herpes lesions. Type of breathing was also associated with oral herpes lesions (p = .031). The OHIP-14 mean distribution among the groups was not statistically significant (p > .05).

CONCLUSION

Bruxism and type of breathing were associated with self-reported oral herpes lesions in Brazilian para-athletes.

Epidemiology of herpes simplex virus type 2 in Latin America and the Caribbean: systematic review, meta-analyses and metaregressions

Objective

To characterise epidemiology of herpes simplex virus type 2 (HSV-2) in Latin America and the Caribbean.

Methods

HSV-2 reports were systematically reviewed and synthesised, and findings were reported following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Meta-analyses and metaregressions were conducted.

Finding

102 relevant reports were identified including 13 overall incidence measures, 163 overall (and 402 stratified) seroprevalence measures, and 7 and 10 proportions of virus detection in genital ulcer disease and in genital herpes, respectively. Pooled mean seroprevalence was 20.6% (95% CI 18.7% to 22.5%) in general populations, 33.3% (95% CI 26.0% to 41.0%) in intermediate-risk populations, 74.8% (95% CI 70.6% to 78.8%) in female sex workers, and 54.6% (95% CI 47.4% to 61.7%) in male sex workers, men who have sex with men and transgender people. In general populations, seroprevalence increased from 9.6% (95% CI 7.1% to 12.4%) in those aged <20 years to 17.9% (95% CI 13.6% to 22.5%) in those aged 20–30, 27.6% (95% CI 21.4% to 34.2%) in those aged 30–40 and 38.4% (95% CI 32.8% to 44.2%) in those aged >40. Compared with women, men had lower seroprevalence with an adjusted risk ratio (ARR) of 0.68 (95% CI 0.60 to 0.76). Seroprevalence declined by 2% per year over the last three decades (ARR of 0.98, 95% CI 0.97 to 0.99). Pooled mean proportions of HSV-2 detection in GUD and genital herpes were 41.4% (95% CI 18.9% to 67.0%) and 91.1% (95% CI 82.7% to 97.2%), respectively.

Conclusions

One in five adults is HSV-2 infected, a higher level than other world regions, but seroprevalence is declining. Despite this decline, HSV-2 persists as the aetiological cause of nearly half of GUD cases and almost all of genital herpes cases.

Epidemiology of herpes simplex virus type 2 in sub-Saharan Africa: Systematic review, meta-analyses, and meta-regressions

BACKGROUND

Herpes simplex virus type 2 (HSV-2) infection is a prevalent, sexually transmitted infection with a sizable disease burden that is highest in sub-Saharan Africa. This study aimed to characterize HSV-2 epidemiology in this region.

METHODS

Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2 related findings up to August 23, 2020. Meta-analyses and meta-regressions were conducted.

FINDINGS

From 218 relevant publications, 451 overall outcome measures and 869 stratified measures were extracted. Pooled incidence rates ranged between 2.4-19.4 per 100 person-years across populations. Pooled seroprevalence was lowest at 37.3% (95% confidence interval (CI): 34.9-39.7%) in general populations and high in female sex workers and HIV-positive individuals at 62.5% (95% CI: 54.8-70.0%) and 71.3% (95% CI: 66.5-75.9%), respectively. In general populations, pooled seroprevalence increased steadily with age. Compared to women, men had a lower seroprevalence with an adjusted risk ratio (ARR) of 0.61 (95% CI: 0.56-0.67). Seroprevalence has decreased in recent decades with an ARR of 0.98 (95% CI: 0.97-0.99) per year. Seroprevalence was highest in Eastern and Southern Africa. Pooled HSV-2 proportion in genital ulcer disease was 50.7% (95% CI: 44.7-56.8%) and in genital herpes it was 97.3% (95% CI: 84.4-100%).

INTERPRETATION

Seroprevalence is declining by 2% per year, but a third of the population is infected. Age and geography play profound roles in HSV-2 epidemiology. Temporal declines and geographic distribution of HSV-2 seroprevalence mirror that of HIV prevalence, suggesting sexual risk behavior has been declining for three decades. HSV-2 is the etiological cause of half of genital ulcer disease and nearly all genital herpes cases with limited role for HSV-1.

FUNDING

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

Epidemiology of herpes simplex virus type 2 in sub-Saharan Africa: Systematic review, meta-analyses, and meta-regressions

BACKGROUND

Herpes simplex virus type 2 (HSV-2) infection is a prevalent, sexually transmitted infection with a sizable disease burden that is highest in sub-Saharan Africa. This study aimed to characterize HSV-2 epidemiology in this region.

METHODS

Cochrane and PRISMA guidelines were followed to systematically review, synthesize, and report HSV-2 related findings up to August 23, 2020. Meta-analyses and meta-regressions were conducted.

FINDINGS

From 218 relevant publications, 451 overall outcome measures and 869 stratified measures were extracted. Pooled incidence rates ranged between 2.4-19.4 per 100 person-years across populations. Pooled seroprevalence was lowest at 37.3% (95% confidence interval (CI): 34.9-39.7%) in general populations and high in female sex workers and HIV-positive individuals at 62.5% (95% CI: 54.8-70.0%) and 71.3% (95% CI: 66.5-75.9%), respectively. In general populations, pooled seroprevalence increased steadily with age. Compared to women, men had a lower seroprevalence with an adjusted risk ratio (ARR) of 0.61 (95% CI: 0.56-0.67). Seroprevalence has decreased in recent decades with an ARR of 0.98 (95% CI: 0.97-0.99) per year. Seroprevalence was highest in Eastern and Southern Africa. Pooled HSV-2 proportion in genital ulcer disease was 50.7% (95% CI: 44.7-56.8%) and in genital herpes it was 97.3% (95% CI: 84.4-100%).

INTERPRETATION

Seroprevalence is declining by 2% per year, but a third of the population is infected. Age and geography play profound roles in HSV-2 epidemiology. Temporal declines and geographic distribution of HSV-2 seroprevalence mirror that of HIV prevalence, suggesting sexual risk behavior has been declining for three decades. HSV-2 is the etiological cause of half of genital ulcer disease and nearly all genital herpes cases with limited role for HSV-1.

FUNDING

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

[The role of herpesviruses in development of diseases of the urogenital tract and infertility in women]

This review presents the data on the spreading of all known human herpesviruses (НHVs) in female urogenital tract. According to the WHO almost 500 million people worldwide suffer from genital infection caused by НHVs. НHVs were detected in various inflammatory diseases of female upper and lower genital tract (vaginitis and cervicitis), in extrauterine pregnancy (in fallopian tubes), in infertility (cervical channel, endometrium and ovaries). Herpes simplex virus 1 (HSV‑1) was identified for the first time in oocytes after failed in vitro fertilization (IVF). НHVs produce negative effect on the entire reproductive process from conception to childbirth. It was established that HSV, cytomegalovirus (CMV) and human herpesvirus 6 (HHV-6) markedly increase the risk of spontaneous abortion, preterm birth and stillbirth. Intrauterine НHV infection is a major cause of congenital malformations. Data on humoral and cell immunity in genital herpesvirus infections (НHVI) are also reviewed. Intravaginal HSV‑2 infection changes cell composition of vaginal mucosa, i.e., together with cells mobilized from the blood, protective role is performed by resident memory T‑cells (TRM), natural killer cells (NK‑cells) and regulatory T‑cells (Treg) whose function consists in maintaining the balance of the activities of lymphocytes. Constant НHVI spreading is largely explained by transition of primary infection to potentially reactivating latent form, since latent virus is unavailable to immune recognition and medicines. The genome editing system CRISPR/Cas9 can recognize and modify not only active but also latent viruses. The promising pilot results with the use of this system offer the possibility of developing innovative technologies for НHV elimination and НHVI eradication.

Antiviral activity of 1,4-disubstituted-1,2,3-triazoles against HSV-1 in vitro

BACKGROUND

Herpes simplex virus 1 (HSV-1) affects a large part of the adult population. Anti-HSV-1 drugs, such as acyclovir, target thymidine kinase and viral DNA polymerase. However, the emerging of resistance of HSV-1 alerts for the urgency in developing new antivirals with other therapeutic targets. Thus, this study evaluated a series of 1,4-disubstituted-1,2,3-triazole derivatives against HSV-1 acute infection and provided deeper insights into the possible mechanisms of action.

METHODS

Human fibroblast cells (HFL-1) were infected with HSV-1 17syn+ and treated with the triazole compounds at 50 μM for 24 h. The 50% effective drug concentration (EC₅₀) was determined for the active compounds. Their cytotoxicity was also evaluated in HFL-1 with the 50% cytotoxic concentration (CC₅₀) determined using CellTiter-Glo^® solution. The most promising compounds were evaluated by virucidal activity and influence on virus egress, DNA replication and transcription, and effect on an acyclovir-resistant HSV-1 strain.

RESULTS

Compounds 3 ((E)-4-methyl-N'-(2-(4-(phenoxymethyl)-1H-1,2,3-triazol1yl)benzylidene)benzenesulfonohydrazide) and 4 (2,2'-(4,4'-((1,3-phenylenebis(oxy))bis(methylene))bis(1H-1,2,3-triazole-4,1 diyl)) dibenzaldehyde) were the most promising, with an EC₅₀ of 16 and 21 μM and CC₅₀ of 285 and 2,593 μM, respectively. Compound 3 was able to inhibit acyclovir-resistant strain replication and to interfere with virus egress. Both compounds did not affect viral DNA replication, but inhibited significantly the expression of ICP0, ICP4 and gC. Compound 4 also affected the transcription of UL30 and ICP34.5.

CONCLUSIONS

Our findings demonstrated that these compounds are promising antiviral candidates with different mechanisms of action from acyclovir and further studies are merited.

Herpes Simplex Virus 1 (HSV-1) 0ΔNLS Live-Attenuated Vaccine Protects against Ocular HSV-1 Infection in the Absence of Neutralizing Antibody in HSV-1 gB T Cell Receptor-Specific Transgenic Mice

The contribution of T cell and antibody responses following vaccination in resistance to herpes simplex virus 1 (HSV-1) infection continues to be rigorously investigated. In the present article, we explore the contribution of CD8+ T cells specific for the major antigenic epitope for HSV-1 glycoprotein B (gB498-505, gB) in C57BL/6 mice using a transgenic mouse (gBT-I.1) model vaccinated with HSV-1 0ΔNLS. gBT-I.1-vaccinated mice did not generate a robust neutralization antibody titer in comparison to the HSV-1 0ΔNLS-vaccinated wild-type C57BL/6 counterpart. Nevertheless, the vaccinated gBT-I.1 mice were resistant to ocular challenge with HSV-1 compared to vehicle-vaccinated animals based on survival and reduced corneal neovascularization but displayed similar levels of corneal opacity. Whereas there was no difference in the virus titer recovered from the cornea comparing vaccinated mice, HSV-1 0ΔNLS-vaccinated animals possessed significantly less infectious virus during acute infection in the trigeminal ganglia (TG) and brain stem compared to the control-vaccinated group. These results correlated with a significant increase in gB-elicited interferon-γ (IFN-γ), granzyme B, and CD107a and a reduction in lymphocyte activation gene 3 (LAG-3), programmed cell death 1 (PD-1), and T cell immunoglobulin and mucin domain-containing protein 3 (TIM-3) expressed by TG infiltrating gB-specific CD8+ T cells from the HSV-1 0ΔNLS-vaccinated group. Antibody depletion of CD8+ T cells in HSV-1 0ΔNLS-vaccinated mice rendered animals highly susceptible to virus-mediated mortality similar to control-vaccinated mice. Collectively, the HSV-1 0ΔNLS vaccine is effective against ocular HSV-1 challenge, reducing ocular neovascularization and suppressing peripheral nerve virus replication in the near absence of neutralizing antibody in this unique mouse model.IMPORTANCE The role of CD8+ T cells in antiviral efficacy using a live-attenuated virus as the vaccine is complicated by the humoral immune response. In the case of the herpes simplex virus 1 (HSV-1) 0ΔNLS vaccine, the correlate of protection has been defined to be primarily antibody driven. The current study shows that in the near absence of anti-HSV-1 antibody, vaccinated mice are protected from subsequent challenge with wild-type HSV-1 as measured by survival. The efficacy is lost following depletion of CD8+ T cells. Whereas increased survival and reduction in virus replication were observed in vaccinated mice challenged with HSV-1, cornea pathology was mixed with a reduction in neovascularization but no change in opacity. Collectively, the study suggests CD8+ T cells significantly contribute to the host adaptive immune response to HSV-1 challenge following vaccination with an attenuated virus, but multiple factors are involved in cornea pathology in response to ocular virus challenge.

The association between herpes simplex virus type 1 infection and Alzheimer's disease

There is growing evidence demonstrating the relationship between herpes simplex virus type 1 (HSV-1) infection and Alzheimer's disease (AD). We searched PubMed, Embase, and Cochrane databases for relevant articles. The Newcastle-Ottawa Scale (NOS) was used to evaluate the qualities of these studies. Pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated using random-effects models. We also performed subgroup analyses stratified by apolipoprotein ε4 (APOE ε4), NOS score, and the method of confirming AD. A total of 21 studies between 1990 and 2020 were identified. The pooled OR suggested that HSV-1 infection is a risk factor of AD: pooled OR 1.40 (95% CI: 1.13-1.75; I² = 3%, P = 0.42). In the subgroup analyses, the pooled ORs of HSV-1 infection associated with AD were 0.75 (95% CI: 0.24-2.37) among the APOE ε4-positive individuals; 0.85 (95% CI: 0.61-1.17) among the APOE ε4-negative individuals; 1.51 (95% CI: 1.10-2.06) in the high NOS score studies; 1.23 (95% CI: 0.85-1.76) in the moderate NOS score studies; 1.47 (95% CI: 1.16-1.87) in the clinical diagnosis group, and 1.20 (95% CI: 0.77-1.87) in the autopsy group. Our up-to-date systematic review and meta-analysis suggest that HSV-1 infection is a risk factor of AD.

Herpes simplex virus: global infection prevalence and incidence estimates, 2016

Objective

To generate global and regional estimates for the prevalence and incidence of herpes simplex virus (HSV) type 1 and type 2 infection for 2016.

Methods

To obtain data, we undertook a systematic review to identify studies up to August 2018. Adjustments were made to account for HSV test sensitivity and specificity. For each World Health Organization (WHO) region, we applied a constant incidence model to pooled prevalence by age and sex to estimate the prevalence and incidence of HSV types 1 and 2 infections. For HSV type 1, we apportioned infection by anatomical site using pooled estimates of the proportions that were oral and genital.

Findings

In 2016, an estimated 491.5 million people (95% uncertainty interval, UI: 430.4 million–610.6 million) were living with HSV type 2 infection, equivalent to 13.2% of the world’s population aged 15–49 years. An estimated 3752.0 million people (95% UI: 3555.5 million–3854.6 million) had HSV type 1 infection at any site, equivalent to a global prevalence of 66.6% in 0–49-year-olds. Differing patterns were observed by age, sex and geographical region, with HSV type 2 prevalence being highest among women and in the WHO African Region.

Conclusion

An estimated half a billion people had genital infection with HSV type 2 or type 1, and several billion had oral HSV type 1 infection. Millions of people may also be at higher risk of acquiring human immunodeficiency virus (HIV), particularly women in the WHO African Region who have the highest HSV type 2 prevalence and exposure to HIV.

Herpes simplex virus type 1 epidemiology in Africa: Systematic review, meta-analyses, and meta-regressions

OBJECTIVE

To assess herpes simplex virus type 1 (HSV-1) epidemiology in Africa.

METHODS

This systematic review was conducted per the Cochrane Collaboration guidelines. Findings were reported following the PRISMA guidelines. Research questions were addressed using random-effects meta-analyses and meta-regressions.

RESULTS

Forty-three overall (and 69 stratified) HSV-1 seroprevalence measures, and 18 and eight proportions of HSV-1 viral detection in genital ulcer disease (GUD) and in genital herpes, respectively, were extracted from 37 reports. Pooled mean seroprevalence was 67.1% (95% confidence interval (CI): 54.7-78.5%) in children, and 96.2% (95% CI: 95.0-97.3%) in adults. Across age groups, pooled mean was 44.4% (95% CI: 29.9-59.3%) in ≤5 years-old, 85.6% (95% CI: 81.0-89.6%) in 6-15 years-old, 93.3% (95% CI: 89.2-96.6%) in 16-25 years-old, and 93.8% (95% CI: 84.6-99.4%) in >25 years-old. Age explained 78.8% of seroprevalence variation. Pooled mean proportion of HSV-1 detection was 0.4% (95% CI: 0.0-1.5%) in GUD, and 1.2% (95% CI: 0.0-4.0%) in genital herpes.

CONCLUSIONS

HSV-1 is universally prevalent in Africa, at higher levels than other regions, with no evidence for declines in seroprevalence in recent decades. Nearly every person acquires the infection in childhood through oral-to-oral transmission, before sexual debut. Sexual oral-to-genital and genital-to-genital transmission appear very limited.

Characterizing herpes simplex virus type 1 and type 2 seroprevalence declines and epidemiological association in the United States

Objective

Assessing the epidemiological association between herpes simplex virus type 1 (HSV-1) and type 2 (HSV-2) infections in the United States, and characterizing the trends in the standardized HSV-1 and HSV-2 antibody prevalences (seroprevalences), 1999–2016.

Methods

Source of data was the cross-sectional and nationally-representative biennial surveys of the National Health and Nutrition Examination Survey (NHANES). All nine NHANES rounds for 1999–2016 were included in analysis. Datasets of these rounds were combined and analyzed accounting for survey design and applying weighting procedures. Logistic regressions were used to identify associations with seropositivity. Sensitivity analyses were conducted.

Results

Odds of HSV-1 infection declined by 2.84% (95% CI: 1.70%-4.00%) annually among men, and by 2.22% (95% CI: 1.23%-3.21%) among women. Declines were highest at younger ages. Odds of HSV-2 infection declined by 2.23% (95% CI: 0.71%-3.82%) annually among men, and by 2.89% (95% CI: 1.57%-4.28%) among women. Odds ratio of the association between HSV-2 and HSV-1 seropositivity was 0.71 (95% CI: 0.60–0.84) for men and 0.81 (95% CI: 0.72–0.91) for women, after adjustment for age, ethnicity, and year.

Conclusion

HSV-1 and HSV-2 seroprevalences showed a strong declining trend for at least two decades, for both sexes and for the different ethnicities, possibly reflecting improvements in hygiene and living conditions (for HSV-1), and safer sexual behavior (for HSV-2). HSV-1 seroprevalence declines are most pronounced among young individuals. There is evidence for cross protection between the two infections, suggestive of HSV-1 seropositivity being partially protective against HSV-2 infection.