Herpes Simplex Virus Type 2 Transmission Research Articles

Herpes Simplex Virus Type 1 Infection Induces the Formation of Tunneling Nanotubes.

Herpes simplex virus type 1 (HSV-1) is human specific virus. The intercellular transmission of HSV-1 is essential in its pathogenesis. The tunneling nanotube (TNT), a new mode connecting distant cells, has been found to play an important role in the spread of various viruses like human immunodeficiency virus (HIV) and influenza virus. However, whether HSV-1 can be transmitted through TNTs has not been confirmed. The purpose of this study was to clarify this, and further to determine the effect of inhibiting the actin-related protein 2/3 (Arp2/3) complex on the intercellular transmission of HSV-1. A scanning electron microscope and fluorescence microscope detected the formation of TNTs between HSV-1 infected cells. Envelope glycoprotein D (gD) and envelope glycoprotein E (gE) of HSV-1 and viral particles were observed in TNTs. Treatment with CK666, an inhibitor of the Arp2/3 complex, reduced the number of TNTs by approximately 40-80%. At the same time, the DNA level of HSV-1 in cells and the number of plaque formation units (PFU) were also reduced by nearly 30%. These findings indicated that TNT contributes to HSV-1 transmission and that the inhibition of the Arp2/3 complex could impair HSV-1 transmission, which not only provides a novel insight into the transmission mode of HSV-1, but also a putative new antiviral target.

Molecular Epidemiology and Risk Factors of Herpes Simplex Virus Type 2 in Pregnant Women

Background: Herpes simplex virus type 2 (HSV-2) infection is the main cause of genital and neonatal herpes infections. It has considerable public health importance among women as the virus may lead to adverse outcomes in pregnancy and neonatal infection. This study determines the molecular epidemiology and risk factors of HSV-2 infection among pregnant women. Methods: In this cross-sectional study, all pregnant women admitted to three university hospitals for natural birth and Caesarean sections were enrolled. HSV detection and typing were carried out based on PCR and reverse dot blotting method, respectively. ANOVA and bivariate correlations were used to analyze the data. Results: In this study, the prevalence of genital herpes infection was 5.7%. A significant positive correlation was found between age group < 25 years and HSV-2 shedding (P = 0.026). Twelve participants (60%) with HSV-2 shedding were younger than 25. A significant correlation was found between the presence of genital lesion and HSV-2 (? = 0.02). Among participants with HSV-2 infection, the use of condom was low. Neonatal complications were not seen in newborns from mothers with HSV-2 shedding. Conclusion: PCR assay may help in promoting early diagnosis and more effective treatment for patients. Also, it shortens hospital stay and enhances patients’ condition. HSV-2 transmission is rapid following the onset of sexual activity and likely to result in the significant prevalence of genital disease.

Primary HSV-2 Infection in Early Pregnancy Results in Transplacental Viral Transmission and Dose-Dependent Adverse Pregnancy Outcomes in a Novel Mouse Model.

Herpes simplex virus type 2 (HSV-2) infection affects 24 million births annually and is associated with adverse pregnancy outcomes, including neonatal herpes; however, the mechanisms underlying in utero transmission of HSV-2 are largely unknown. We examined the effects of primary HSV-2 infection during early pregnancy on gestational outcomes in a novel, clinically relevant mouse model. Pregnant C57BL/6 mice were infected intravaginally with 102–105 pfu/mL HSV-2 on gestation day (gd) 4.5. Controls were infected, nonpregnant, diestrus-staged mice and pregnant, uninfected mice. Compared to nonpregnant mice, pregnant mice were 100-fold more susceptible to HSV-2 infection. Three days post-inoculation (gd7.5), viral DNA was present in implantation sites, but pregnancy outcomes were largely unaffected by infection. Eight days post-inoculation (gd12.5), HSV-2 DNA persisted in placental tissues, resulting in inflammation and hemorrhage. Fetal and placental weights were reduced and fetal loss was observed with high viral doses. HSV-2 DNA and increased expression of pro-inflammatory mediators were detected in fetal tissues at gd12.5, signifying viral transmission and fetal infection, even with low viral doses. This mouse model shows a dose-dependent effect of primary HSV-2 infection on pregnancy outcomes and suggests that fetal loss may occur due to placental inflammation, thus providing valuable insight into in utero transmission of HSV-2.

What Is the Burden of Heterosexually Acquired HIV Due to HSV-2? Global and Regional Model-Based Estimates of the Proportion and Number of HIV Infections Attributable to HSV-2 Infection.

Biological and epidemiological evidence suggest that herpes simplex virus type 2 (HSV-2) elevates HIV acquisition and transmission risks. We improved previous estimates of the contribution of HSV-2 to HIV infections by using a dynamic transmission model. World Health Organization regions. We developed a mathematical model of HSV-2/HIV transmission among 15- to 49-year-old heterosexual, non-drug-injecting populations, calibrated using region-specific demographic and HSV-2/HIV epidemiological data. We derived global and regional estimates of the contribution of HSV-2 to HIV infection over 10 years [the transmission population-attributable fraction (tPAF)] under 3 additive scenarios, assuming: (1) HSV-2 increases only HIV acquisition risk (conservative); (2) HSV-2 also increases HIV transmission risk (liberal); and (3) HIV or antiretroviral therapy (ART) also modifies HSV-2 transmission risk, and HSV-2 decreases ART effect on HIV transmission risk (fully liberal). Under the conservative scenario, the predicted tPAF was 37.3% (95% uncertainty interval: 33.4%-43.2%), and an estimated 5.6 (4.5-7.0) million incident heterosexual HIV infections were due to HSV-2 globally over 2009-2018. The contribution of HSV-2 to HIV infections was largest for the African region [tPAF = 42.6% (38.0%-51.2%)] and lowest for the European region [tPAF = 11.2% (7.9%-13.8%)]. The tPAF was higher among female sex workers, their clients, and older populations, reflecting their higher HSV-2 prevalence. The tPAF was approximately 50% and 1.3- to 2.4-fold higher for the liberal or fully liberal scenario than the conservative scenario across regions. HSV-2 may have contributed to at least 37% of incident HIV infections in the past decade worldwide, and even more in Africa, and may continue to do so despite increased ART access unless future improved HSV-2 control measures, such as vaccines, become available.

Cluster of Symptomatic Graft-to-Host Transmission of Herpes Simplex Virus Type 1 in an Endothelial Keratoplasty Setting

PurposeDescemet's membrane endothelial keratoplasty (DMEK) is becoming the gold standard to treat corneal endothelial dysfunctions worldwide. Compared with conventional penetrating keratoplasty, infectious complications after DMEK are ill defined. We describe the clinical picture of 2 DMEK recipients, operated on the same day and in the same clinic, who developed atypical herpes simplex virus type 1 (HSV-1) infection in the transplant recipient eye within days post-DMEK. Because recipients received cornea tissue from 2 different donors prepared by the same eye bank, the likelihood of a common HSV-1 source was determined.DesignCase series.ParticipantsTwo DMEK recipients who developed atypical intraocular HSV-1 disease shortly after surgery and surplus cornea specimens of 6 donors.MethodsSurplus cornea donor (pre-DMEK cornea remnants and conditioned cornea storage and transport media) and recipient samples (post-DMEK aqueous humor) were assayed for HSV-1 DNA and infectious virus by real-time polymerase chain reaction (RT-PCR) and cell culture, respectively. Target-enriched whole viral genome sequencing was performed on HSV-1 DNA–positive ocular specimens.Main Outcome MeasuresClinical picture of atypical intraocular HSV-1 infection post-DMEK and presence and homology of HSV-1 genomes between ocular specimens of DMEK donors and recipients.ResultsHerpes simplex virus type 1 DNA was detected in aqueous humor and donor cornea specimens of both DMEK cases, but not in the cornea remnants of 6 randomly selected donors processed by the same eye bank. Infectious HSV-1 was isolated from the cornea remnant and corresponding culture medium of 1 cornea donor. Notably, whole-genome sequencing of virus DNA-positive specimens demonstrated exceptionally high genetic similarity between HSV-1 strains in recipient and donor specimens of both DMEK cases.ConclusionsData indicate cross-contamination of cornea grafts during DMEK preparation with subsequent graft-to-host HSV-1 transmission that caused atypical sight-threatening herpetic eye disease shortly after DMEK. Ophthalmologists should be aware that HSV-1 transmission by DMEK is possible and can lead to atypical ocular disease, a condition that can easily be prevented by taking appropriate technical and clinical measures at both eye bank and surgical levels.

Analytic Characterization of the Herpes Simplex Virus Type 2 Epidemic in the United States, 1950-2050.

Background We analytically characterized the past, present, and future levels and trends of the national herpes simplex virus type 2 (HSV-2) epidemic in the United States.MethodsA population-level mathematical model was constructed to describe HSV-2 transmission dynamics and was fitted to the data series of the National Health and Nutrition Examination Survey.ResultsOver 1950–2050, antibody prevalence (seroprevalence) increased rapidly from 1960, peaking at 19.9% in 1983 in those aged 15–49 years, before reversing course to decline to 13.2% by 2020 and 8.5% by 2050. Incidence rate peaked in 1971 at 11.9 per 1000 person-years, before declining by 59% by 2020 and 70% by 2050. Annual number of new infections peaked at 1 033 000 in 1978, before declining to 667 000 by 2020 and 600 000 by 2050. Women were disproportionately affected, averaging 75% higher seroprevalence, 95% higher incidence rate, and 71% higher annual number of infections. In 2020, 78% of infections were acquired by those 15–34 years of age.ConclusionsThe epidemic has undergone a major transition over a century, with the greatest impact in those 15–34 years of age. In addition to 47 million prevalent infections in 2020, high incidence will persist over the next 3 decades, adding >600 000 new infections every year.

Herpes Simplex Virus Type 2 Seroprevalence in Pregnant Women in Urmia, Northwest of Iran, during 2014-2015

Background:HSV-2 seroprevalence has been shown to be a potential sign of infection in pregnant women, and it could be applied to check HSV-2 transmission. This study evaluated the anti-HSV-2 IgG prevalence in pregnant women who were referred to health centers in Urmia, Northwest of Iran, during 2014-2015.Methods:Serum samples were collected from 86 pregnant women and tested for Anti-HSV-2-specific IgG using a commercial enzyme-linked immunosorbent assays kit. Results:Five (5.8%) pregnant women showed the presence of Anti-HSV-2-specific IgG antibodies. Previous abortion was reported in 16 (19.7%) and 2 subjects in the seronegative and seropositive groups, respectively. Conclusion:Data from the present study indicate a lower number of HSV-2 seropositives among the pregnant women in Urmia. This reduction would be a result of low number of studied subjects used in the present study; hence, assessing a large sample is recommended.

Herpes simplex virus-2 transmission following solid organ transplantation: Donor-derived infection and transplantation from prior organ recipients.

Owing to limited availability of donor organs, previous solid organ transplant (SOT) recipients are increasingly considered as potential organ donors. We report donor-derived transmission of herpes simplex virus type-2 (HSV-2) to two clusters of SOT recipients with transmission from the original donor and an HSV-2-infected recipient who subsequently became a donor. We reviewed medical records of the donors and recipients in both clusters. Pre-transplant serology and virological features of HSV-2 were characterized. Genotyping of HSV-2 isolates to determine potential for donor transmission of HSV-2 through transplantation of organs from prior organ recipients was performed. A kidney-pancreas recipient died day 9 post transplant. Following confirmation of brain death, the lungs and recently transplanted kidney were donated to two further recipients. The liver was not retrieved, but biopsy confirmed HSV-2 infection. Testing on the original donor showed negative HSV-2 polymerase chain reaction and HSV immunoglobulin (Ig)M, but positive HSV-2 IgG. The liver recipient from the original donor developed HSV-2 hepatitis and cutaneous infection that responded to treatment with intravenous acyclovir. In the second cluster, lung and kidney recipients both developed HSV-2 viremia that was successfully treated with antiviral therapy. Genotyping of all HSV-2-positive samples showed 100% sequence homology for three recipients. Donor-derived HSV infection affected two clusters of recipients because of transplantation of organs from a prior organ recipient. HSV should be considered as a possible cause of illness in febrile SOT recipients in the immediate post-transplant period and may cause disseminated disease and re-infection in HSV-2-seropositive recipients. Testing of HSV serology and prophylaxis may be considered in SOT recipients not receiving cytomegalovirus prophylaxis.

Herpes Simplex Virus Suppressive Therapy in Herpes Simplex Virus-2/Human Immunodeficiency Virus-1 Coinfected Women Is Associated With Reduced Systemic CXCL10 But Not Genital Cytokines.

Herpes simplex virus type-2 (HSV-2) may heighten immune activation and increase human immunodeficiency virus 1 (HIV-1) replication, resulting in greater infectivity and faster HIV-1 disease progression. An 18-week randomized, placebo-controlled crossover trial of 500 mg valacyclovir twice daily in 20 antiretroviral-naive women coinfected with HSV-2 and HIV-1 was conducted and HSV-2 suppression was found to significantly reduce both HSV-2 and HIV-1 viral loads both systemically and the endocervical compartment. To determine the effect of HSV-2 suppression on systemic and genital mucosal inflammation, plasma specimens, and endocervical swabs were collected weekly from volunteers in the trial and cryopreserved. Plasma was assessed for concentrations of 31 cytokines and chemokines; endocervical fluid was eluted from swabs and assayed for 14 cytokines and chemokines. Valacyclovir significantly reduced plasma CXCL10 but did not significantly alter other cytokine concentrations in either compartment. These data suggest genital tract inflammation in women persists despite HSV-2 suppression, supporting the lack of effect on transmission seen in large scale efficacy trials. Alternative therapies are needed to reduce persistent mucosal inflammation that may enhance transmission of HSV-2 and HIV-1.

Incidence and risk factors for herpes simplex virus type 2 seroconversion among pregnant women in Uganda: A prospective study.

Herpes simplex virus type 2 (HSV-2) acquired during pregnancy is associated with adverse outcomes such as perinatal HSV-2 transmission. HSV-2 seroconversion occurs within four weeks of HSV-2 acquisition. There was neither documented incidence nor risk factors for HSV-2 seroconversion during pregnancy in Uganda. The objective of this study was to determine the incidence and risk factors for HSV-2 seroconversion among pregnant women in Mulago Hospital, Uganda. A prospective study of 200 consenting HSV-2-negative women between 26 and 28 weeks of gestation was done between November 2013 and October 2014. HSV-2 serostatus was determined using HerpeSelect HSV-2 enzyme-linked immunosorbent assay (ELISA). Interviewer-administered questionnaires were used to collect socio-demographic characteristics and sexual history. Human immunodeficiency virus (HIV) serostatus was obtained from antenatal records. A total of 191 women completed follow-up and repeat HSV-2 serology by 38 weeks. Negative binomial regression analysis was used to estimate risk ratios for risk factors for HSV-2 seroconversion. Of 191 women, 15 (7.9%) seroconverted during pregnancy. Having multiple sexual partners, being in polygamous unions, and having HIV-positive serostatus were found to be risk factors for HSV-2 seroconversion. The incidence of HSV-2 seroconversion during pregnancy in Uganda was high. Multiple sexual partners, polygamy, and HIV-positive serostatus were risk factors for HSV-2 seroconversion during pregnancy. Strengthening health education on the avoidance of multiple sexual partners during pregnancy is paramount in prevention of HSV-2 seroconversion.

Prevention of vaginal and rectal herpes simplex virus type 2 transmission in mice: mechanism of antiviral action.

Topical microbicides to stop sexually transmitted diseases, such as herpes simplex virus type 2 (HSV-2), are urgently needed. The emerging field of nanotechnology offers novel suitable tools for addressing this challenge. Our objective was to study, in vitro and in vivo, antiherpetic effect and antiviral mechanisms of several polyanionic carbosilane dendrimers with anti-HIV-1 activity to establish new potential microbicide candidates against sexually transmitted diseases. Plaque reduction assay on Vero cells proved that G2-S16, G1-S4, and G3-S16 are the dendrimers with the highest inhibitory response against HSV-2 infection. We also demonstrated that our dendrimers inhibit viral infection at the first steps of HSV-2 lifecycle: binding/entry-mediated events. G1-S4 and G3-S16 bind directly on the HSV-2, inactivating it, whereas G2-S16 adheres to host cell-surface proteins. Molecular modeling showed that G1-S4 binds better at binding sites on gB surface than G2-S16. Significantly better binding properties of G1-S4 than G2-S16 were found in an important position for affecting transition of gB trimer from G1-S4 prefusion to final postfusion state and in several positions where G1-S4 could interfere with gB/gH–gL interaction. We demonstrated that these polyanionic carbosilan dendrimers have a synergistic activity with acyclovir and tenofovir against HSV-2, in vitro. Topical vaginal or rectal administration of G1-S4 or G2-S16 prevents HSV-2 transmission in BALB/c mice in values close to 100%. This research represents the first demonstration that transmission of HSV-2 can be blocked by vaginal/rectal application of G1-S4 or G2-S16, providing a step forward to prevent HSV-2 transmission in humans.

Risk factors for incident HSV-2 infections among a prospective cohort of HIV-1-discordant couples in China

ObjectivesIdentification of risk factors is essential for developing herpes simplex virus type 2 (HSV-2) prevention interventions that could also reduce HIV-1 transmission, particularly among HIV-1-discordant couples.MethodsA prospective cohort study was...

Establishment of HSV1 latency in immunodeficient mice facilitates efficient in vivo reactivation.

The establishment of latent infections in sensory neurons is a remarkably effective immune evasion strategy that accounts for the widespread dissemination of life long Herpes Simplex Virus type 1 (HSV1) infections in humans. Periodic reactivation of latent virus results in asymptomatic shedding and transmission of HSV1 or recurrent disease that is usually mild but can be severe. An in-depth understanding of the mechanisms regulating the maintenance of latency and reactivation are essential for developing new approaches to block reactivation. However, the lack of a reliable mouse model that supports efficient in vivo reactivation (IVR) resulting in production of infectious HSV1 and/or disease has hampered progress. Since HSV1 reactivation is enhanced in immunosuppressed hosts, we exploited the antiviral and immunomodulatory activities of IVIG (intravenous immunoglobulins) to promote survival of latently infected immunodeficient Rag mice. Latently infected Rag mice derived by high dose (HD), but not low dose (LD), HSV1 inoculation exhibited spontaneous reactivation. Following hyperthermia stress (HS), the majority of HD inoculated mice developed HSV1 encephalitis (HSE) rapidly and synchronously, whereas for LD inoculated mice reactivated HSV1 persisted only transiently in trigeminal ganglia (Tg). T cells, but not B cells, were required to suppress spontaneous reactivation in HD inoculated latently infected mice. Transfer of HSV1 memory but not OVA specific or naïve T cells prior to HS blocked IVR, revealing the utility of this powerful Rag latency model for studying immune mechanisms involved in control of reactivation. Crossing Rag mice to various knockout strains and infecting them with wild type or mutant HSV1 strains is expected to provide novel insights into the role of specific cellular and viral genes in reactivation, thereby facilitating identification of new targets with the potential to block reactivation.

Neonatal Herpes Simplex Virus Type 1 Infection and Jewish Ritual Circumcision With Oral Suction: A Systematic Review.

Jewish ritual circumcision rarely but occasionally includes a procedure involving direct oral suction of the wound, which can expose an infant to infection with herpes simplex virus type 1 (HSV-1). This practice has provoked international controversy in recent years, but no systematic review of the clinical literature has previously been published. We designed this review to identify and synthesize all published studies examining the association between circumcision with direct oral suction and HSV-1 infection. Our search strategy identified 6 published case series or case reports, documenting 30 cases between 1988 and 2012. Clinical findings were consistent with transmission of infection during circumcision, although the evidence base is limited by the small number of infections and incomplete case data. Published evidence suggests that circumcision with direct oral suction has resulted in severe neonatal illness and death from HSV-1 transmission, but further research is necessary to clarify the risk of infection.

Persistence of mucosal T-cell responses to herpes simplex virus type 2 in the female genital tract.

Relatively little is known about the human T cell response to HSV-2 in the female genital tract, a major site of heterosexual HSV-2 acquisition, transmission and reactivation. In order to understand the role of local mucosal immunity in HSV-2 infection, T cell lines were expanded from serial cervical cytobrush samples from 30 HSV-2 infected women and examined for reactivity to HSV-2. Approximately 3% of the CD3+ T cells isolated from the cervix were HSV-2 specific and of these, a median of 91.3% were CD4+ while a median of 3.9% were CD8+. HSV-2 specific CD4+ T cells expanded from the cervix were not only more frequent than CD8+ T cells but also exhibited greater breadth in terms of antigenic reactivity. T cells directed at the same HSV-2 protein were often detected in serial cervical cytobrush samples and in blood. Thus, broad and persistent mucosal T cell responses to HSV-2 were detected in the female genital tract of HSV-2+ women suggesting that these cells are resident at the site of HSV-2 infection. Understanding the role of these T cells at this biologically relevant site will be central to the elucidation of adaptive immune mechanisms involved in controlling HSV-2 disease.

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Daily acyclovir to decrease herpes simplex virus type 2 (HSV-2) transmission from HSV-2/HIV-1 coinfected persons: a randomized controlled trial.

Daily suppressive therapy with valacyclovir reduces risk of sexual transmission of herpes simplex virus type 2 (HSV-2) in HSV-2-serodiscordant heterosexual couples by 48%. Whether suppressive therapy reduces HSV-2 transmission from persons coinfected with HSV-2 and human immunodeficiency virus type 1 (HIV-1) is unknown. Within a randomized trial of daily acyclovir 400 mg twice daily in African HIV-1 serodiscordant couples, in which the HIV-1-infected partner was HSV-2 seropositive, we identified partnerships in which HIV-1-susceptible partners were HSV-2 seronegative to estimate the effect of acyclovir on risk of HSV-2 transmission. We randomly assigned 911 HSV-2/HIV-1-serodiscordant couples to daily receipt of acyclovir or placebo. We observed 68 HSV-2 seroconversions, 40 and 28 in acyclovir and placebo groups, respectively (HSV-2 incidence, 5.1 cases per 100 person-years; hazard ratio [HR], 1.35 [95% confidence interval, .83-2.20]; P = .22). Among HSV-2-susceptible women, vaginal drying practices (adjusted HR, 44.35; P = .004) and unprotected sex (adjusted HR, 9.91; P = .002) were significant risk factors for HSV-2 acquisition; having more children was protective (adjusted HR, 0.47 per additional child; P = .012). Among HSV-2-susceptible men, only age ≤30 years was associated with increased risk of HSV-2 acquisition (P = .016). Treatment of African HSV-2/HIV-1-infected persons with daily suppressive acyclovir did not decrease risk of HSV-2 transmission to susceptible partners. More-effective prevention strategies to reduce HSV-2 transmission from HIV-1-infected persons are needed.

Incident HSV-2 Infections Are Common Among HIV-1-discordant Couples

The synergy between herpes simplex virus type 2 (HSV-2) and human immunodeficiency virus type 1 (HIV-1) is well known, but lack of knowledge about the epidemiology of HSV-2 acquisition in HIV-1-discordant couples hampers development of HSV-2 prevention interventions that could reduce HIV-1 transmission. HIV-1-discordant couples were enrolled in Nairobi, Kenya, and followed for up to 2 years. HSV-2 status was determined using HerpeSelect HSV-2 ELISA. Correlates of prevalence and incidence were assessed. RESULTS.: Of 469 HIV-1-discordant couples, at baseline, 353 (75.3%) were affected by HSV-2, of which 189 (53.5%) were concordantly HSV-2 seropositive and 164 (46.5%) were HSV-2-discordant. Prevalence was lowest among HIV-1-uninfected men (39.9%) compared to HIV-1-infected women (64.8%), HIV-1-infected men (66.7%), and HIV-1-uninfected women (68.5%). During follow-up, HSV-2 seroincidence was 14.9 per 100 person-years. Incidence was 1.6-fold higher among females compared to males (95% confidence interval [CI], 1.00-2.48) and 2.5-fold higher in HIV-1-infected compared to uninfected women (95% CI, 1.12-5.74). At least 30% of incident HSV-2 infections originated from an outside partner. The high HSV-2 prevalence and incidence in HIV-1-discordant couples in sub-Saharan Africa suggest HSV-2 treatment and prevention could be an effective targeted strategy to reduce HSV-2 and HIV-1 transmission in this high-risk population.

P3.235 Global Ecological Study of HIV and HSV-2 Prevalence

BackgroundHIV and herpes simplex virus type-2 (HSV-2) are infections transmitted predominantly through sexual intercourse. We explored the ecological association between the prevalence of HIV and HSV-2 among human populations through...

Herpes simplex virus type 2 cross-sectional seroprevalence and the estimated rate of neonatal infections among a cohort of rural Malawian female adolescents

ObjectiveTo assess herpes simplex virus type 2 (HSV-2) seroprevalence among rural Malawian adolescent women and estimate the number of neonatal herpes infections among infants of these adolescents.MethodsA longitudinal cohort study...