In vitro modulator responsiveness of 655 CFTR variants found in people with cystic fibrosis

BACKGROUND

In 2017, the US Food and Drug Administration initiated expansion of drug labels for the treatment of cystic fibrosis (CF) to include CF transmembrane conductance regulator (CFTR) gene variants based on in vitro functional studies. This study aims to identify CFTR variants that result in increased chloride (Cl-) transport function by the CFTR protein after treatment with the CFTR modulator combination elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA). These data may benefit people with CF (pwCF) who are not currently eligible for modulator therapies.

METHODS

Plasmid DNA encoding 655 CFTR variants and wild-type (WT) CFTR were transfected into Fisher Rat Thyroid cells that do not natively express CFTR. After 24 h of incubation with control or TEZ and ELX, and acute addition of IVA, CFTR function was assessed using the transepithelial current clamp conductance assay. Each variant's forskolin/cAMP-induced baseline Cl- transport activity, responsiveness to IVA alone, and responsiveness to the TEZ/ELX/IVA combination were measured in three different laboratories. Western blots were conducted to evaluate CFTR protein maturation and complement the functional data.

RESULTS AND CONCLUSIONS

253 variants not currently approved for CFTR modulator therapy showed low baseline activity (<10 % of normal CFTR Cl- transport activity). For 152 of these variants, treatment with ELX/TEZ/IVA improved the Cl- transport activity by ≥10 % of normal CFTR function, which is suggestive of clinical benefit. ELX/TEZ/IVA increased CFTR function by ≥10 percentage points for an additional 140 unapproved variants with ≥10 % but <50 % of normal CFTR function at baseline. These findings significantly expand the number of rare CFTR variants for which ELX/TEZ/IVA treatment should result in clinical benefit.

Expansion of the HSV-2-specific T cell repertoire in skin after immunotherapeutic HSV-2 vaccine

The skin at the site of HSV-2 reactivation is enriched for HSV-2-specific T cells. To evaluate whether an immunotherapeutic vaccine could elicit skin-based memory T cells, we studied skin biopsies and HSV-2-reactive CD4+ T cells from peripheral blood mononuclear cells (PBMCs) by T cell receptor β (TRB) sequencing before and after vaccination with a replication-incompetent whole virus HSV-2 vaccine candidate (HSV529). The representation of HSV-2-reactive CD4+ TRB sequences from PBMCs in the skin TRB repertoire increased after the first vaccine dose. We found sustained expansion after vaccination of unique, skin-based T-cell clonotypes that were not detected in HSV-2-reactive CD4+ T cells isolated from PBMCs. In one participant a switch in immunodominance occurred with the emergence of a T cell receptor (TCR) αβ pair after vaccination that was not detected in blood. This TCRαβ was shown to be HSV-2-reactive by expression of a synthetic TCR in a Jurkat-based NR4A1 reporter system. The skin in areas of HSV-2 reactivation possesses an oligoclonal TRB repertoire that is distinct from the circulation. Defining the influence of therapeutic vaccination on the HSV-2-specific TRB repertoire requires tissue-based evaluation.

Factors associated with pubertal growth outcomes in cystic fibrosis: Early Growth and Puberty in CF

BACKGROUND

Pubertal delays in children with cystic fibrosis (CF) have historically been common. It is unclear to what degree puberty is affected in the new era of CF care or the role of early nutritional status. We hypothesized that more favorable early growth trajectories are associated with improved pubertal growth outcomes.

METHODS

We used data from the United States CF Foundation Patient Registry to analyze associations between early weight-for-length/body mass index (WFL-BMI) growth trajectories and pubertal outcomes, using peak height velocity (PHV) and age at PHV (APHV) as proxy measures for puberty in addition to adult height (defined as height at age 18 years). Our analysis consisted of shape invariant mixed modeling and multivariable linear regression.

RESULTS

Our sample consisted of 9,186 people with CF aged 18 to 21 years between 2010-2019. APHV was earliest and PHV/adult height were highest in those with WFL-BMI always >50th percentile from 0-6 years. However, there was no difference after adjusting for key covariates. Receiving CF transmembrane conductance regulator (CFTR) modulator therapy in childhood was associated with being taller at 18 years, by 0.92 cm in males (p=0.048) and 1.02 cm in females (p=0.010) in adjusted models. Higher height z-score at 2 years was associated with improved APHV and PHV for males and improved adult height for both males and females (p<0.001) in adjusted models.

CONCLUSIONS

Early height, but not early WFL-BMI trajectories, may be associated with pubertal growth outcomes. CFTR modulator therapy shows the potential to improve pubertal growth outcomes, but further research is necessary.

Web-Based Survey Piloting Process as a Model for Developing and Testing Past Contraceptive Use and Pregnancy History: Cystic Fibrosis Case Study

BACKGROUND

Individuals with complex, chronic diseases are now living longer, making reproductive health an important topic to address in the health care setting. Self-respondent surveys are a feasible way to collect past contraceptive use and pregnancy history to assess contraceptive safety and effectiveness. Because sensitive topics, such as contraception and pregnancy outcomes, can vary across social groups or cultures, piloting questions and evaluating survey administration procedures in the target population are necessary for precise and reliable responses before wide distribution.

OBJECTIVE

This study aimed to develop a precise and reliable survey instrument and related procedures among individuals with cystic fibrosis regarding contraceptive use and obstetrical history.

METHODS

We piloted and tested web-based questions related to contraceptive use and pregnancy history among 50 participants with and those without cystic fibrosis aged 18 to 45 years using a 3-tier process. Findings from each tier informed changes to the questionnaire before testing in the subsequent tier. Tier 1 used cognitive pretesting to assess question understanding and the need for memory prompts. In tier 2, we used test-retest self- and interviewer-administered approaches to assess question reliability, evaluate response missingness, and determine confidence between 2 types of survey administration approaches. In tier 3, we tested the questionnaire for clarity, time to complete, and whether additional prompts were necessary.

RESULTS

In tier 1, respondents suggested improvements to the web-based survey questions and to the written and visual prompts for better recall regarding past contraceptive use. In tier 2, the test-retest reliability between self- and interviewer-administrative procedures of "ever use" contraceptive method questions was similar, with percent absolute agreement ranging between 84% and 100%. When the survey was self-administered, the percentage of missing responses was higher and respondent confidence about month and year when contraceptive methods were used was lower. Most respondents reported that they preferred the self-administered survey because it was more convenient and faster to complete.

CONCLUSIONS

Our 3-tier process to pilot web-based survey questions related to contraceptive and obstetrical history in our complex disease population helped us tailor content and format questions before wide dissemination to our target population. Results from this pilot study informed the subsequent larger study design to include a 10% respondent test-retest self- and interviewer-administered quality control component to better inform imputation procedures of missing data.

Quantifying variation in home spirometry in people with cystic fibrosis during baseline health, and associations with clinical outcomes

BACKGROUND

Home spirometry is increasingly used to monitor lung function in people with cystic fibrosis (pwCF). Although decreases in lung function in the setting of increased respiratory symptoms are consistent with a pulmonary exacerbation (PEx), the interpretation of home spirometry during asymptomatic periods of baseline health is unclear. The aims of this study were to determine the variation in home spirometry in pwCF during asymptomatic periods of baseline health and to identify associations between this variation and PEx.

METHODS

Near-daily home spirometry measurements were obtained from a cohort of pwCF enrolled in a long-term study of the airway microbiome. Associations between the degree of variation in home spirometry and the time to next PEx were evaluated.

RESULTS

Thirteen subjects (mean age of 29 years and mean percent predicted forced expiratory volume in one second [ppFEV1] of 60) provided a median of 204 spirometry readings taken during 40 periods of baseline health. The mean week-to-week within-subject level of variation in ppFEV1 was 15.2 ± 6.2%. The degree of variation in ppFEV1 during baseline health was not associated with time to PEx.

CONCLUSIONS

Variation in ppFEV1 measured with near-daily home spirometry in pwCF during periods of baseline health exceeded the variation in ppFEV1 expected in clinic spirometry (based on ATS guidelines). The degree of variation in ppFEV1 during baseline health was not associated with time to PEx. These data are relevant for guiding interpretation of home spirometry.

A new path for CF clinical trials through the use of historical controls

BACKGROUND

Given future challenges in conducting large randomized, placebo controlled trials for future CF therapeutics development, we evaluated the potential for using external historical controls to either enrich or replace traditional concurrent placebo groups in CF trials.

METHODS

The study included data from sequentially completed, randomized, controlled clinical trials, EPIC and OPTIMIZE respectively, evaluating optimal antibiotic therapy to reduce the risk of pulmonary exacerbation in children with early Pseudomonas aeruginosa infection. The primary treatment effect in OPTIMIZE, the risk of pulmonary exacerbation associated with azithromycin, was re-estimated in alternative designs incorporating varying numbers of participants from the earlier trial (EPIC) as historical controls. Bias and precision of these estimates were characterized. Propensity scores were derived to adjust for baseline differences across study populations, and both Poisson and Cox regression were used to estimate treatment efficacy.

RESULTS

Replacing 86 OPTIMIZE placebo participants with 304 controls from EPIC to mimic a fully historically controlled trial resulted an 8% reduction in risk of pulmonary exacerbations (Hazard ratio (HR):0.92 95% CI 0.61, 1.34) when not adjusting for key baseline differences between study populations. After adjustment, a 37% decrease in risk of exacerbation (HR:0.63, 95% CI 0.50, 0.80) was estimated, comparable to the estimate from the original trial comparing the 86 placebo participants to 77 azithromycin participants on azithromycin (45%, HR:0.55, 95% CI: 0.34, 0.86). Other adjusted approaches provided similar estimates for the efficacy of azithromycin in reducing exacerbation risk: pooling all controls from both studies provided a HR of 0.60 (95% x`CI 0.46, 0.77) and augmenting half the OPTIMIZE placebo participants with EPIC controls gave a HR 0.63 (95% CI 0.48, 0.82).

CONCLUSIONS

The potential exists for future CF trials to utilize historical control data. Careful consideration of both the comparability of controls and of optimal methods can reduce the potential for biased estimation of treatment effects.

Tissue-Resident-Memory CD8+ T Cells Bridge Innate Immune Responses in Neighboring Epithelial Cells to Control Human Genital Herpes

Tissue-resident-memory T cells (TRM) populate the body's barrier surfaces, functioning as frontline responders against reencountered pathogens. Understanding of the mechanisms by which CD8TRM achieve effective immune protection remains incomplete in a naturally recurring human disease. Using laser capture microdissection and transcriptional profiling, we investigate the impact of CD8TRM on the tissue microenvironment in skin biopsies sequentially obtained from a clinical cohort of diverse disease expression during herpes simplex virus 2 (HSV-2) reactivation. Epithelial cells neighboring CD8TRM display elevated and widespread innate and cell-intrinsic antiviral signature expression, largely related to IFNG expression. Detailed evaluation via T-cell receptor reconstruction confirms that CD8TRM recognize viral-infected cells at the specific HSV-2 peptide/HLA level. The hierarchical pattern of core IFN-γ signature expression is well-conserved in normal human skin across various anatomic sites, while elevation of IFI16, TRIM 22, IFITM2, IFITM3, MX1, MX2, STAT1, IRF7, ISG15, IFI44, CXCL10 and CCL5 expression is associated with HSV-2-affected asymptomatic tissue. In primary human cells, IFN-γ pretreatment reduces gene transcription at the immediate-early stage of virus lifecycle, enhances IFI16 restriction of wild-type HSV-2 replication and renders favorable kinetics for host protection. Thus, the adaptive immune response through antigen-specific recognition instructs innate and cell-intrinsic antiviral machinery to control herpes reactivation, a reversal of the canonical thinking of innate activating adaptive immunity in primary infection. Communication from CD8TRM to surrounding epithelial cells to activate broad innate resistance might be critical in restraining various viral diseases.

Long-term azithromycin use is not associated with QT prolongation in children with cystic fibrosis

Chronic Azithromycin (AZM) is a common treatment for lung infection. Among adults at risk of cardiac events, AZM use has been associated with cardiovascular harm. We assessed cardiovascular safety of AZM among children with CF, as a secondary analysis of a placebo-controlled, clinical trial, in which study drug was taken thrice-weekly for a planned 18 months. Safety assessments using electrocardiogram (ECG) occurred at study enrollment, and then after 3 weeks and 18 months of participation. Among 221 study participants with a median of 18 months follow-up, increased corrected QT interval (QTc) of ≥30 msec was rare, at 3.4 occurrences per 100 person-years; and incidence of QTc prolongation was no higher in the AZM arm than the placebo arm (1.8 versus 5.4 per 100 person-years). No persons experienced QTc intervals above 500 msec. Long-term chronic AZM use was not associated with increased QT prolongation.

Multigroup, Adaptively Randomized Trials Are Advantageous for Comparing Coronavirus Disease 2019 (COVID-19) Interventions

In this commentary, the authors explain and call for a broader use of outcome-adaptive randomization when designing clinical trials to test multiple COVID-19 interventions. This design potentially reduces the number of deaths or other adverse outcomes incurred during a trial.

The effect of testosterone on ovulatory function in transmasculine individuals

BACKGROUND

An estimated 1.4 million persons in the United States identify as transgender or nonbinary, signifying that their gender identity does not correspond with their assigned sex at birth. Individuals assigned female at birth may seek gender-affirming hormone therapy with testosterone. No studies have directly examined ovulatory function in transmasculine individuals using injectable testosterone.

OBJECTIVES

Our primary objective was to determine the effect of testosterone on ovulatory suppression in transmasculine individuals. Secondary objectives were to determine predictors of ovulation in transmasculine individuals on testosterone, and to assess the effect of testosterone on antimüllerian hormone.

MATERIALS AND METHODS

This prospective observational study recruited participants from a community clinic that provides gender-affirming hormone therapy. Enrolled individuals were assigned female at birth and were currently using or seeking to initiate masculinizing therapy with injectable testosterone esters (transmasculine individuals). Over a 12-week study period, participants collected daily urine samples for pregnanediol-3-glucoronide testing and completed daily electronic bleeding diaries. We assessed monthly serum mid-dosing interval testosterone, estradiol and sex hormone binding globulin, and antimüllerian hormone values at baseline and study end. Ovulation was defined as pregnanediol-3-glucoronide greater than 5 μg/mL for 3 consecutive days. The primary outcome was the proportion of participants who ovulated during the study period. We examined predictors of ovulation such as age, length of time on testosterone, serum testosterone levels, body mass index, and bleeding pattern.

RESULTS

From July to November 2018, we enrolled 32 individuals; 20 completed the study (14 continuing testosterone users, 6 new users). Median age was 23 years (range 18-37 years). Bleeding or spotting during the study period was noted by 41% of participants (13/32). Among continuing users, median testosterone therapy duration was 11 months (range 1-60 months). A single ovulation was observed out of a total of 61 combined months of testosterone use; however, several transient rises in pregnanediol-3-glucoronide followed by bleeding episodes were suggestive of 7 dysfunctional ovulatory cycles among 7 individuals. There was no difference in antimüllerian hormone from baseline to 12 weeks between participants initiating testosterone and continuing users of testosterone. We did not have the power to examine our intended predictors given the low numbers of ovulatory events, but found that longer time on testosterone and presence of vaginal bleeding over 12 weeks were associated with transient rises in pregnanediol-3-glucoronide.

CONCLUSION

This study suggests that testosterone rapidly induces hypothalamic-pituitary-gonadal suppression, resulting in anovulation in a proportion of new users. Importantly, these data also suggest that some long-term testosterone users break through the hormonal suppression and experience an ovulatory event, thereby raising concerns pertaining to the need for contraception in transmasculine individuals engaged in sexual intercourse with sperm-producing partners. Given the small number of overall participants, this work is hypothesis generating. Larger studies are needed to confirm and to clarify these findings.

Building global development strategies for cf therapeutics during a transitional cftr modulator era

As CFTR modulator therapy transforms the landscape of cystic fibrosis (CF) care, its lack of uniform access across the globe combined with the shift towards a new standard of care creates unique challenges for the development of future CF therapies. The advancement of a full and promising CF therapeutics pipeline remains a necessary priority to ensure maximal clinical benefits for all people with CF. It is through collaboration across the global CF community that we can optimize the evaluation and approval process of new therapies. To this end, we must identify areas for which harmonization is lacking and for which efficiencies can be gained to promote ethical, feasible, and credible study designs amidst the changing CF care landscape. This article summarizes the counsel from core advisors across multiple international regions and clinical trial networks, developed during a one-day workshop in October 2019. The goal of the workshop was to identify, in consideration of the highly transitional era of CFTR modulator availability, the drug development areas for which global alignment is currently uncertain, and paths forward that will enable advancement of CF therapeutic development.

Viral Genetics Modulate Orolabial Herpes Simplex Virus Type 1 Shedding in Humans

BACKGROUND

Orolabial herpes simplex virus type 1 (HSV-1) infection has a wide spectrum of severity in immunocompetent persons. To study the role of viral genotype and host immunity, we characterized oral HSV-1 shedding rates and host cellular response, and genotyped viral strains, in monozygotic (MZ) and dizygotic (DZ) twins.

METHODS

A total of 29 MZ and 22 DZ HSV-1-seropositive twin pairs were evaluated for oral HSV-1 shedding for 60 days. HSV-1 strains from twins were genotyped as identical or different. CD4+ T-cell responses to HSV-1 proteins were studied.

RESULTS

The median per person oral HSV shedding rate was 9% of days that a swab was obtained (mean, 10.2% of days). A positive correlation between shedding rates was observed within all twin pairs, and in the MZ and DZ twins. In twin subsets with sufficient HSV-1 DNA to genotype, 15 had the same strain and 14 had different strains. Viral shedding rates were correlated for those with the same but not different strains. The median number of HSV-1 open reading frames recognized per person was 16. The agreement in the CD4+ T-cell response to specific HSV-1 open reading frames was greater between MZ twins than between unrelated persons (P = .002).

CONCLUSION

Viral strain characteristics likely contribute to oral HSV-1 shedding rates.

Primary and Repeated Respiratory Viral Infections Among Infants in Rural Nepal

BACKGROUND

Respiratory viruses cause significant morbidity and death in infants; 99% of such deaths occur in resource-limited settings. Risk factors for initial and repeated respiratory viral infections in young infants in resource-limited settings have not been well described.

METHODS

From 2011 to 2014, a birth cohort of infants in rural Nepal was enrolled and followed with weekly household-based active surveillance for respiratory symptoms until 6 months of age. Respiratory illness was defined as having any of the following: fever, cough, wheeze, difficulty breathing, and/or a draining ear. We tested nasal swabs of infants with respiratory illness for multiple respiratory viruses by using a reverse transcription polymerase chain reaction assay. The risk of primary and repeated infections with the same virus was evaluated using Poisson regression.

RESULTS

Of 3528 infants, 1726 (49%) had a primary infection, and 419 (12%) had a repeated infection. The incidences of respiratory viral infection in infants were 1816 per 1000 person-years for primary infections and 1204 per 1000 person-years for repeated infection with the same virus. Exposure to other children and male sex were each associated with an increased risk for primary infection (risk ratios, 1.13 [95% confidence interval (CI), 1.06-1.20] and 1.14 [95% CI, 1.02-1.27], respectively), whereas higher maternal education was associated with a decreased risk for both primary and repeated infections (risk ratio, 0.96 [95% CI, 0.95-0.98]). The incidence of subsequent infection did not change when previous infection with the same or another respiratory virus occurred. Illness duration and severity were not significantly different in the infants between the first and second episodes for any respiratory virus tested.

CONCLUSIONS

In infants in rural Nepal, repeated respiratory virus infections were frequent, and we found no decrease in illness severity with repeated infections and no evidence of replacement with another virus. Vaccine strategies and public health interventions that provide durable protection in the first 6 months of life could decrease the burden of repeated infections by multiple respiratory viruses, particularly in low-resource countries.

Herpes Simplex Virus Shedding Rate: Surrogate Outcome for Genital Herpes Recurrence Frequency and Lesion Rates, and Phase 2 Clinical Trials End Point for Evaluating Efficacy of Antivirals

Background

We tested whether genital herpes simplex virus (HSV) shedding is an appropriate surrogate outcome for the clinical outcome of genital herpes lesions in studies of HSV-2 antiviral interventions.

Methods

We analyzed prospective data from natural history studies and clinical trials of antiviral agents for HSV-2 in which HSV-2-seropositive participants provided self-collected anogenital swab specimens daily over ≥25 days for HSV DNA quantitation by polymerase chain reaction (PCR). Genital recurrences were self-reported.

Results

Among 674 participants, genital HSV shedding was detected on 17% of days, and genital lesions were reported on 10% of days. Within the same session, HSV shedding rates were strongly correlated with lesion rates (ρ = 0.61, P < .0001). The relative reduction in the recurrence rate was 72% (P = .041) for recipients of the antiviral agent pritelivir as compared to recipients of placebo, but it decreased to 21% (P = .75) after adjustment for HSV shedding rate. When evaluating valacyclovir and acyclovir, adjustment for the HSV shedding rate also led to a reduced association of these antivirals with the recurrence rate. Overall, 40%-82% of the antiviral effect on recurrences was explained by its effect on HSV shedding.

Conclusion

HSV genital shedding measured by PCR analysis in swab specimens self-collected daily is an appropriate surrogate outcome for genital herpes lesions because it is in the causal pathway to recurrences.

Quadrivalent HPV vaccine in HIV-1-infected early adolescent girls and boys in Kenya: Month 7 and 12 post vaccine immunogenicity and correlation with immune status

INTRODUCTION

In sub-Saharan Africa, a generation of HIV-1-infected children is approaching the age of sexual debut and becoming at risk for HPV infection and its sequelae. We assessed safety and immunogenicity of the quadrivalent HPV (qHPV) vaccine in HIV-1-infected adolescents.

METHODS

In an open-label trial among Kenyan, HIV-1-infected adolescents aged 9-14 years, we administered the qHPV vaccine at 0, 2 and 6 months and measured antibody titers to HPV-16, 18, 6 and 11 at month 7 and 12 post-vaccination. Measures of immunogenic response from HIV-1-negative historical cohorts from Africa and HIV-1 positive adolescent cohorts from the USA were used for comparison.

RESULTS

We enrolled 100 girls and 80 boys with a median age of 12 years and median baseline CD4 cell count of 684 (IQR 478, 935) cells/µL. One hundred and fifty four (86%) were receiving antiretroviral therapy for a median of 4.5 (IQR 2.3, 6.3) years; 110 (71%) had <400 copies of plasma HIV-1 RNA/mL. Of 189 enrolled children, 179 received all three doses. Two hundred and eighty five (64%) of 445 adverse events were injection site reactions; none were greater than grade 2. Of 6 Serious Adverse Events (SAEs), none were considered vaccine related. Seroconversion to HPV-18, 16, 11, 6 at month 7 occurred in 93.3%, 98.3%, 97.2% and 99.6% of vaccine recipients; similar rates have been reported in historical controls. The mean log₁₀ HPV antibody titer measured at month 7 increased with each log₁₀ increase in CD4 by 1.4 (95% CI: 1.1-1.7) for HPV-18; 1.2 (0.9-1.4) for HPV-16; 1.1 (0.8-1.3) for HPV-11; 0.7 (0.5-1.0) for HPV-6 (all p < 0.0001).

CONCLUSION

Almost all Kenyan HIV-1-infected adolescents mounted an immune response comparable to other immunized populations. HPV antibody titers were higher in those with preserved CD4 cell counts. Longer term-follow up will determine sustainability of the immune response. ClinicalTrials.gov number, NCT00557245.

Model-based estimation of superinfection prevalence from limited datasets

Humans can be infected sequentially by different strains of the same virus. Estimating the prevalence of so-called 'superinfection' for a particular pathogen is vital because superinfection implies a failure of immunologic memory against a given virus despite past exposure, which may signal challenges for future vaccine development. Increasingly, viral deep sequencing and phylogenetic inference can discriminate distinct strains within a host. Yet, a population-level study may misrepresent the true prevalence of superinfection for several reasons. First, certain infections such as herpes simplex virus (HSV-2) only reactivate single strains, making multiple samples necessary to detect superinfection. Second, the number of samples collected in a study may be fewer than the actual number of independently acquired strains within a single person. Third, detecting strains that are relatively less abundant can be difficult, even for other infections such as HIV-1 where deep sequencing may identify multiple strains simultaneously. Here we develop a model of superinfection inspired by ecology. We define an infected individual's richness as the number of infecting strains and use ecological evenness to quantify the relative strain abundances. The model uses an EM methodology to infer the true prevalence of superinfection from limited clinical datasets. Simulation studies with known true prevalence are used to contrast our EM method to a standard (naive) calculation. While varying richness, evenness and sampling we quantify the accuracy and precision of our method. The EM method outperforms in all cases, particularly when sampling is low, and richness or unevenness is high. Here, sensitivity to our assumptions about clinical data is considered. The simulation studies also provide insight into optimal study designs; estimates of prevalence improve equally by enrolling more participants or gathering more samples per person. Finally, we apply our method to data from published studies of HSV-2 and HIV-1 superinfection.

Invasive Obstetric Procedures and Cesarean Sections in Women With Known Herpes Simplex Virus Status During Pregnancy

Background

Neonatal herpes is a potentially devastating infection that results from acquisition of herpes simplex virus (HSV) type 1 or 2 from the maternal genital tract at the time of vaginal delivery. Current guidelines recommend (1) cesarean delivery if maternal genital HSV lesions are present at the time of labor and (2) antiviral suppressive therapy for women with known genital herpes to decrease HSV shedding from the genital tract at the time of vaginal delivery. However, most neonatal infections occur in infants born to women without a history of genital HSV, making current prevention efforts ineffective for this group. Although routine serologic HSV testing of women during pregnancy could identify women at higher risk of intrapartum viral shedding, it is uncertain how this knowledge might impact intrapartum management, and a potential concern is a higher rate of cesarean sections among women known to be HSV-2 seropositive.

Methods

To assess the effects of prenatal HSV-2 antibody testing, history of genital herpes, and use of suppressive antiviral medication on the intrapartum management of women, we investigated the frequency of invasive obstetric procedures and cesarean deliveries. We conducted a retrospective cohort study of pregnant women delivering at the University of Washington Medical center in Seattle, Washington. We defined the exposure of interest as HSV-2 antibody positivity or known history of genital herpes noted in prenatal records. The primary outcome was intrapartum procedures including fetal scalp electrode, artificial rupture of membranes, intrauterine pressure catheter, or operative vaginal delivery (vacuum or forceps). The secondary outcome was incidence of cesarean birth. Univariate and multivariable logistic regressions were performed.

Results

From a total of 449 women included in the analysis, 97 (21.6%) were HSV-2 seropositive or had a history of genital herpes (HSV-2/GH). Herpes simplex virus-2/GH women not using suppressive antiviral therapy were less likely to undergo intrapartum procedures than women without HSV-2/GH (odds ratio [OR], 0.49; 95% confidence interval [CI], 0.25–0.95; P = .036), but this relationship was attenuated after adjustment for potential confounders (adjusted OR, 0.69; 95% CI, 0.34–1.41; P = .31). There was no difference in intrapartum procedures for women on suppressive therapy versus women without HSV-2/GH (OR, 1.17; 95% CI, 0.66–2.07; P = .60). Similar proportions of cesarean sections were performed within each group of women: 25% without history of HSV-2/GH, 30% on suppressive treatment, and 28.1% without suppressive treatment (global, P = .73).

Conclusions

In this single-site study, provider awareness of genital herpes infection either by HSV serotesting or history was associated with fewer invasive obstetric procedures shown to be associated with neonatal herpes, but it was not associated with an increased rate of cesarean birth.

Valganciclovir for the Suppression of Epstein-Barr Virus Replication

Epstein-Barr virus (EBV) causes infectious mononucleosis and can lead to lymphoproliferative diseases. We evaluated the effects of valganciclovir on oral EBV shedding in a randomized, double-blind, placebo-controlled study. Twenty-six men received oral valganciclovir or daily placebo for 8 weeks, followed by a 2-week "washout period" and then 8 weeks of the alternative treatment. Valganciclovir reduced the proportion of days with EBV detected from 61.3% to 17.8% (relative risk, 0.28; 95% confidence interval [CI], .21-.41; P < .001), and quantity of virus detected by 0.77 logs (95% CI, .62-.91 logs; P < .001). Further investigations into the impact of valganciclovir on EBV-associated diseases are needed.

Enrichment of herpes simplex virus type 2 (HSV-2) reactive mucosal T cells in the human female genital tract

Local mucosal cellular immunity is critical in providing protection from HSV-2. To characterize and quantify HSV-2-reactive mucosal T cells, lymphocytes were isolated from endocervical cytobrush and biopsy specimens from 17 HSV-2-infected women and examined ex vivo for the expression of markers associated with maturation and tissue residency and for functional T-cell responses to HSV-2. Compared with their circulating counterparts, cervix-derived CD4+ and CD8+ T cells were predominantly effector memory T cells (CCR7-/CD45RA-) and the majority expressed CD69, a marker of tissue residency. Co-expression of CD103, another marker of tissue residency, was highest on cervix-derived CD8+ T cells. Functional HSV-2 reactive CD4+ and CD8+ T-cell responses were detected in cervical samples and a median of 17% co-expressed CD103. HSV-2-reactive CD4+ T cells co-expressed IL-2 and were significantly enriched in the cervix compared with blood. This first direct ex vivo documentation of local enrichment of HSV-2-reactive T cells in the human female genital mucosa is consistent with the presence of antigen-specific tissue-resident memory T cells. Ex vivo analysis of these T cells may uncover tissue-specific mechanisms of local control of HSV-2 to assist the development of vaccine strategies that target protective T cells to sites of HSV-2 infection.

Febrile Rhinovirus Illness During Pregnancy Is Associated With Low Birth Weight in Nepal

Background

Adverse birth outcomes, including low birth weight (LBW), defined as <2500 grams, small-for-gestational-age (SGA), and prematurity, contribute to 60%–80% of infant mortality worldwide and may be related to infections during pregnancy. The aim of this study was to assess whether febrile human rhinovirus (HRV) illness is associated with adverse birth outcomes.

Methods

Active household-based weekly surveillance was performed for respiratory illness episodes in pregnant women as part of a community-based, prospective, randomized trial of maternal influenza immunization in rural Nepal. Rhinovirus (HRV) febrile illness episodes were defined as fever plus cough, sore throat, runny nose, and/or myalgia with HRV detected on mid-nasal swab. Multivariate regression analysis evaluated the association between febrile HRV respiratory illness and adverse birth outcomes.

Results

Overall, 96 (3%) of 3693 pregnant women had HRV-positive febrile respiratory illnesses. Infants born to pregnant women with HRV febrile illness had a 1.6-fold increased risk of being LBW compared with those with non-HRV febrile illness (28 of 96 [38%] vs 109 of 458 [24%]; relative risk [RR], 1.6; 95% confidence interval [CI], 1.1–2.3). No difference in risk of LBW was observed between infants born to mothers with non-HRV febrile respiratory illness and those without respiratory illness during pregnancy (109 of 458 [24%] vs 552 of 2220 [25%], respectively; RR, 1.0; 95% CI, 0.8–1.2).

Conclusions

Febrile illness due to rhinovirus during pregnancy was associated with increased risk of LBW in a rural South Asian population. Interventions to reduce the burden of febrile respiratory illness due to rhinovirus during pregnancy may have a significant impact on LBW and subsequent infant mortality.

Worldwide circulation of HSV-2 × HSV-1 recombinant strains

Homo sapiens harbor two distinct, medically significant species of simplexviruses, herpes simplex virus (HSV)-1 and HSV-2, with estimated divergence 6-8 million years ago (MYA). Unexpectedly, we found that circulating HSV-2 strains can contain HSV-1 DNA segments in three distinct genes. Using over 150 genital swabs from North and South America and Africa, we detected recombinants worldwide. Common, widely distributed gene UL39 genotypes are parsimoniously explained by an initial >457 basepair (bp) HSV-1 × HSV-2 crossover followed by back-recombination to HSV-2. Blocks of >244 and >539 bp of HSV-1 DNA within genes UL29 and UL30, respectively, have reached near fixation, with a minority of strains retaining sequences we posit as ancestral HSV-2. Our data add to previous in vitro and animal work, implying that in vivo cellular co-infection with HSV-1 and HSV-2 yields viable interspecies recombinants in the natural human host.

Outcomes in necrotizing soft tissue infections treated with therapeutic plasma exchange

BACKGROUND

Treatment of necrotizing soft tissue infections (NSTIs) includes prompt surgical debridement and antibiotics, but despite standard care, the morbidity and mortality remain high. Since therapeutic plasma exchange (TPE) has been considered for treatment of severe sepsis, this study evaluates the efficacy of TPE for patients with NSTI.

STUDY DESIGN AND METHODS

This is a retrospective study of patients with diagnosis of NSTI who received treatment with and without TPE over an 11-year period. The primary outcome was in-hospital mortality.

RESULTS

Fifty-two patients with NSTI treated with TPE (TPE group) and 125 patients with NSTI not treated with TPE (non-TPE group) were assessed. Nineteen (36.5%) patients died in the TPE group, and 35 (28%) patients died in the non-TPE group. Within the TPE group, there was significant improvement in white blood cell (WBC) count and sodium levels 7 days after TPE treatment, but no improvement in creatinine. Inverse probability weighting based on propensity scores was used to compare survival in the TPE and non-TPE groups and demonstrated that TPE was associated with an increased odds of death (odds ratio, 2.8). A second analysis matched for six variables yielded 31 pairs and demonstrated no significant difference in mortality or length of stay.

CONCLUSIONS

This study describes the largest series of patients with NSTIs treated with TPE and showed no evidence of clinical benefit. Further carefully designed studies with meaningful clinical endpoints would prove useful in assessing reproducibility and determining if there is a role for TPE in other forms of severe sepsis.

First estimates of the global and regional incidence of neonatal herpes infection

Background

Neonatal herpes is a rare but potentially devastating condition (60% fatality without treatment). Transmission usually occurs during delivery from mothers with herpes simplex virus type 1 (HSV-1) or HSV-2 genital infection. The global burden has never been quantified. We developed a novel methodology for burden estimation and present first WHO global and regional estimates of the annual number of neonatal herpes cases during 2010–2015.

Methods

Previous estimates of HSV-1 and HSV-2 prevalence and incidence in women aged 15–49 years were applied to 2010–2015 birth rates to estimate infections during pregnancy. Published risks of neonatal HSV transmission were then applied according to whether maternal infection was incident or prevalent with HSV-1 or HSV-2 to estimate neonatal herpes cases.

Findings

Globally the overall rate of neonatal herpes was estimated to be ~10 cases per 100,000 births, equivalent to a best-estimate of ~14,000 cases annually (HSV-1: ~4,000; HSV-2: ~10,000). We estimated that the most neonatal herpes cases occurred in Africa, due to high maternal HSV-2 infection and high birth rates. HSV-1 contributed more cases than HSV-2 in the Americas, Europe and Western Pacific. High rates of genital HSV-1 infection and moderate HSV-2 prevalence meant the Americas had the highest overall rate. However, our estimates are highly sensitive to the core assumptions, and considerable uncertainty exists for many settings given sparse underlying data.

Interpretation

These neonatal herpes estimates mark the first attempt to quantify the global burden of this rare but serious condition. Better primary data collection on neonatal herpes is critically needed to reduce uncertainty and refine future estimates. This is particularly important in resource-poor settings where we may have underestimated cases. Nevertheless, these first estimates suggest development of new HSV prevention measures such as vaccines could have additional benefits beyond reducing genital ulcer disease and HSV-associated HIV transmission, through prevention of neonatal herpes.

Funding

World Health Organization

Patterns of human herpesvirus-8 oral shedding among diverse cohorts of human herpesvirus-8 seropositive persons

Background

Human herpesvirus-8 (HHV-8), the etiologic agent of Kaposi sarcoma (KS), establishes lifelong latent infection with periodic lytic replication (“shedding”) at mucosal sites, especially the oropharynx. Patterns of HHV-8 shedding are not well understood, and require elucidation to better predict risk of HHV-8 related malignancies in those infected. We sought to characterize patterns of HHV-8 oropharyngeal shedding among diverse cohorts that enrolled HHV-8 seropositive persons.

Methods

We quantified HHV-8 oral shedding using PCR among HHV-8 seropositive persons who collected at least 14 days of oral swabs in 22 studies on 3 continents. We excluded persons taking antivirals during sampling or any prior use of antiretrovirals in those who were HIV-infected.

Results

248 participants were enrolled from the US, Peru, Cameroon, Uganda, and Kenya; 61 % were men, 58 % were HIV seropositive, and 16 % had KS. Overall, 3,123 of 10,557 samples (29.6 %) had HHV-8 detected. Quantity of virus shed was highly correlated with shedding rate, (ρ = 0.72, p < 0.0001). HHV-8 was detected in ≥1 sample in 55 % of participants with a median of 7 % of days in the US and Kenya, 0 % in Uganda and Peru, and 18 % in Cameroon. Median episode duration was three days, and episodes with high median quantity lasted longer (42 vs 3 days, p < 0.0001). In persons with multiple observations over time, 66 % of shedding rate variance was attributable to differences between individuals.

Conclusions

In HHV-8 infected individuals from diverse settings, oral mucosal shedding rate, quantity, and duration were correlated; individual shedding was highly variable. Studies are needed to determine factors accounting for between-person variation and the relationship of HHV-8 shedding to development of associated diseases.

Consistent viral DNA quantification after prolonged storage at ambient temperature

Long-term storage of biological specimens at low temperatures is costly and impractical in resource limited settings, where the disease burden of chronic viral infections is highest, and the need for research greatest. We examined the necessity of cold storage by comparing the quantity of HHV-8 DNA recovered from swab samples before and after 9-11 months of storage at temperatures of -20 °C, 4 °C and 37 °C. Quantitative levels of HHV-8 DNA remained consistent for laboratory or mucosal swab samples regardless of storage temperature. Freezer storage is determined to be not necessary for mucosal samples destined for HHV-8 DNA quantification.

Effect of Condom Use on Per-act HSV-2 Transmission Risk in HIV-1, HSV-2-discordant Couples

BACKGROUND

The efficacy of condoms for protection against transmission of herpes simplex virus type 2 (HSV-2) has been examined in a variety of populations with different effect measures. Often the efficacy has been assessed as change in hazard of transmission with consistent vs inconsistent use, independent of the number of acts. Condom efficacy has not previously measured on a per-act basis.

METHODS

We examined the per-act HSV-2 transmission rates with and without condom use among 911 African HSV-2 and human immunodeficiency virus type 1 (HIV-1) serodiscordant couples followed for an average of 18 months in an HIV prevention study. Infectivity models were used to associate the log10 probability of HSV-2 transmission over monthly risk periods with reported numbers of protected and unprotected sex acts. Condom efficacy was computed as the proportionate reduction in transmission risk for protected relative to unprotected sex acts.

RESULTS

Transmission of HSV-2 occurred in 68 couples, including 17 with susceptible women and 51 with susceptible men. The highest rate of transmission was from men to women: 28.5 transmissions per 1000 unprotected sex acts. We found that condoms were differentially protective against HSV-2 transmission by sex; condom use reduced per-act risk of transmission from men to women by 96% (P < .001) and marginally from women to men by 65% (P = .060).

CONCLUSIONS

Condoms are recommended as an effective preventive method for heterosexual transmission of HSV-2.

Global and Regional Estimates of Prevalent and Incident Herpes Simplex Virus Type 1 Infections in 2012

Background

Herpes simplex virus type 1 (HSV-1) commonly causes orolabial ulcers, while HSV-2 commonly causes genital ulcers. However, HSV-1 is an increasing cause of genital infection. Previously, the World Health Organization estimated the global burden of HSV-2 for 2003 and for 2012. The global burden of HSV-1 has not been estimated.

Methods

We fitted a constant-incidence model to pooled HSV-1 prevalence data from literature searches for 6 World Health Organization regions and used 2012 population data to derive global numbers of 0-49-year-olds with prevalent and incident HSV-1 infection. To estimate genital HSV-1, we applied values for the proportion of incident infections that are genital.

Findings

We estimated that 3709 million people (range: 3440–3878 million) aged 0–49 years had prevalent HSV-1 infection in 2012 (67%), with highest prevalence in Africa, South-East Asia and Western Pacific. Assuming 50% of incident infections among 15-49-year-olds are genital, an estimated 140 million (range: 67–212 million) people had prevalent genital HSV-1 infection, most of which occurred in the Americas, Europe and Western Pacific.

Conclusions

The global burden of HSV-1 infection is huge. Genital HSV-1 burden can be substantial but varies widely by region. Future control efforts, including development of HSV vaccines, should consider the epidemiology of HSV-1 in addition to HSV-2, and especially the relative contribution of HSV-1 to genital infection.

Oral and Vaginal Tenofovir for Genital Herpes Simplex Virus Type 2 Shedding in Immunocompetent Women: A Double-Blind, Randomized, Cross-over Trial

BACKGROUND

Tenofovir is a potent anti-human immunodeficiency virus (HIV) agent that decreased risk of herpes simplex virus type 2 (HSV-2) acquisition in HIV pre-exposure prophylaxis trials. Whether tenofovir has utility in established HSV-2 disease is unclear.

METHODS

We randomized immunocompetent women with symptomatic HSV-2 infection to oral tenofovir disoproxil fumarate (TDF)/placebo vaginal gel, oral placebo/tenofovir (TFV) vaginal gel, or double placebo (ratio 2:2:1) in a one-way cross-over trial. Women collected genital swabs twice daily for HSV PCR during 4-week lead-in and 5-week treatment phases. The primary intent-to-treat end point was within-person comparison of genital HSV shedding and lesion rates.

RESULTS

64 women completed the lead-in phase and were randomized. Neither TDF nor TFV gel decreased overall shedding or lesion rate in the primary analysis; TFV gel decreased quantity of HSV DNA by -0.50 (-0.86-0.13) log10 copies/mL. In the per-protocol analysis, TDF reduced shedding (relative risk [RR] = 0.74, P = .006) and lesion rates (RR = 0.75, P = .032); quantity of virus shed decreased by 0.41 log10 copies/mL.

CONCLUSIONS

Oral TDF modestly decreased HSV shedding and lesion rate, and quantity of virus shed when used consistently. Vaginal TFV gel decreased quantity of virus shed by 60%. In contrast to effects on HSV-2 acquisition, tenofovir is unlikely to provide clinically meaningful reductions in the frequency of HSV shedding or genital lesions.

CLINICAL TRIALS REGISTRATION

NCT01448616.

Global estimates of prevalent and incident herpes simplex virus type 2 infections in 2012

Background

Herpes simplex virus type 2 (HSV-2) infection causes significant disease globally. Adolescent and adult infection may present as painful genital ulcers. Neonatal infection has high morbidity and mortality. Additionally, HSV-2 likely contributes substantially to the spread of HIV infection. The global burden of HSV-2 infection was last estimated for 2003. Here we present new global estimates for 2012 of the burden of prevalent (existing) and incident (new) HSV-2 infection among females and males aged 15–49 years, using updated methodology to adjust for test performance and estimate by World Health Organization (WHO) region.

Methods and Findings

We conducted a literature review of HSV-2 prevalence studies world-wide since 2000. We then fitted a model with constant HSV-2 incidence by age to pooled HSV-2 prevalence values by age and sex. Prevalence values were adjusted for test sensitivity and specificity. The model estimated prevalence and incidence by sex for each WHO region to obtain global burden estimates. Uncertainty bounds were computed by refitting the model to reflect the variation in the underlying prevalence data. In 2012, we estimate that there were 417 million people aged 15–49 years (range: 274–678 million) living with HSV-2 infection world-wide (11.3% global prevalence), of whom 267 million were women. We also estimate that in 2012, 19.2 million (range: 13.0–28.6 million) individuals aged 15–49 years were newly-infected (0.5% of all individuals globally). The highest burden was in Africa. However, despite lower prevalence, South-East Asia and Western Pacific regions also contributed large numbers to the global totals because of large population sizes.

Conclusions

The global burden of HSV-2 infection is large, leaving over 400 million people at increased risk of genital ulcer disease, HIV acquisition, and transmission of HSV-2 to partners or neonates. These estimates highlight the critical need for development of vaccines, microbicides, and other new HSV prevention strategies.

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

BACKGROUND

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.

METHODS

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.

RESULTS

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).

CONCLUSIONS

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.

Determinants of per-coital-act HIV-1 infectivity among African HIV-1-serodiscordant couples

BACKGROUND

Knowledge of factors that affect per-act infectivity of human immunodeficiency virus type 1 (HIV-1) is important for designing HIV-1 prevention interventions and for the mathematical modeling of the spread of HIV-1.

METHODS

We analyzed data from a prospective study of African HIV-1-serodiscordant couples. We assessed transmissions for linkage within the study partnership, based on HIV-1 sequencing. The primary exposure measure was the HIV-1-seropositive partners' reports of number of sex acts and condom use with their study partner.

RESULTS

Of 3297 couples experiencing 86 linked HIV-1 transmissions, the unadjusted per-act risks of unprotected male-to-female (MTF) and female-to-male (FTM) transmission were 0.0019 (95% confidence interval [CI], .0010-.0037) and 0.0010 (95% CI, .00060-.0017), respectively. After adjusting for plasma HIV-1 RNA of the HIV-1-infected partner and herpes simplex virus type 2 serostatus and age of the HIV-1-uninfected partner, we calculated the relative risk (RR) for MTF versus FTM transmission to be 1.03 (P = .93). Each log(10) increase in plasma HIV-1 RNA increased the per-act risk of transmission by 2.9-fold (95% CI, 2.2-3.8). Self-reported condom use reduced the per-act risk by 78% (RR = 0.22 [95% CI, .11-.42]).

CONCLUSIONS

Modifiable risk factors for HIV-1 transmission were plasma HIV-1 RNA level and condom use, and, in HIV-1-uninfected partners, herpes simplex virus 2 infection, genital ulcers, Trichomonas vaginalis, vaginitis or cervicitis, and male circumcision.

Sample Size for a Binomial Proportion with Autocorrelation

A flexible sample size computation is desired for a binomial outcome consisting of repeated binary measures with autocorrelation over time. This type of outcome is common in viral shedding studies, in which each individual's outcome is a proportion: the number of samples on which virus is detected out of number of samples assessed. Autocorrelation between proximal samples occurs in some conditions such as herpes infection, in which reactivation is episodic. We determine a sample size computation that accounts for: (1) participant-level differences in outcome frequency, (2) autocorrelation in time between samples, and (3) varying number of samples per participant. In addition, we develop a computation appropriate for crossover designs that accounts for the dependence of the investigational treatment effect on the pretreatment detection frequency. The computations are validated through comparison with real and simulated data, and sensitivity to misspecification of parameter values is examined graphically.

Risk Factors for HSV-2 Infection among Sexual Partners of HSV-2/HIV-1 Co-Infected Persons

Background

Herpes simplex virus type 2 (HSV-2) is the most frequent cause of genital ulcer disease worldwide and has been associated with increased risk for HIV-1 acquisition and transmission. We conducted a cross-sectional analysis of risk factors for HSV-2 infection among HIV-1 uninfected partners, whose partners were co-infected with HIV-1 and HSV-2.

Methods

Between November 2004 and April 2007, 3408 HIV-discordant couples, in which the HIV-1 infected partners were HSV-2 seropositive with CD4 250 cells/mm³ or greater, were enrolled in an HSV-2 suppression trial to prevent HIV-1 transmission at 14 sites in 7 African countries. Clinical & behavioral data, HSV-2 and HIV-1 testing were conducted at enrolment. Univariate and multivariate Poisson regression analyses were performed separately, by gender of the HIV-1 infected partner.

Results

Among 3354 HIV-1 uninfected participants, 32% were female and overall 71% were HSV-2 seropositive. Among couples with female HIV-1 infected partners, HIV-1 plasma RNA [aPR 1.03; 95% CI: 0.99 to 1.06; p = 0.11] and CD4 count [aPR 1.00; 95% CI: 0.98 to 1.01; p = 0.48] in the HSV-2/HIV-1 dually infected female and circumcision in the HIV-1 uninfected male partner [aPR 0.94; 95% CI: 0.88 to 1.00; p = 0.06] were not associated with reduced risk of HSV-2 seropositivity, after adjusting for other factors.

Conclusions

In this cross-sectional analysis of African HIV-1 serodiscordant heterosexual couples with prevalent HSV-2 infection in the HIV-1 infected partner, HIV-1 plasma RNA and CD4 count in the dually-infected partner and male circumcision in the HIV-1 uninfected partner were not associated with HSV-2 concordance.

Trial Registration

ClinicalTrials.gov NCT00194519

Daily acyclovir for HIV-1 disease progression in people dually infected with HIV-1 and herpes simplex virus type 2: a randomised placebo-controlled trial

BACKGROUND

Most people infected with HIV-1 are dually infected with herpes simplex virus type 2. Daily suppression of this herpes virus reduces plasma HIV-1 concentrations, but whether it delays HIV-1 disease progression is unknown. We investigated the effect of acyclovir on HIV-1 progression.

METHODS

In a trial with 14 sites in southern Africa and east Africa, 3381 heterosexual people who were dually infected with herpes simplex virus type 2 and HIV-1 were randomly assigned in a 1:1 ratio to acyclovir 400 mg orally twice daily or placebo, and were followed up for up to 24 months. Eligible participants had CD4 cell counts of 250 cells per mL or higher and were not taking antiretroviral therapy. We used block randomisation, and patients and investigators were masked to treatment allocation. Effect of acyclovir on HIV-1 disease progression was defined by a primary composite endpoint of first occurrence of CD4 cell counts of fewer than 200 cells per microL, antiretroviral therapy initiation, or non-trauma related death. As an exploratory analysis, we assessed the endpoint of CD4 falling to <350 cells per microL. Analysis was by intention to treat. The trial is registered with ClinicalTrials.gov, number NCT00194519.

FINDINGS

At enrollment, the median CD4 cell count was 462 cells per microL and median HIV-1 plasma RNA was 4.1 log(10) copies per microL. Acyclovir reduced risk of HIV-1 disease progression by 16%; 284 participants assigned acyclovir versus 324 assigned placebo reached the primary endpoint (hazard ratio [HR] 0.84, 95% CI 0.71-0.98, p=0.03). In those with CD4 counts >or=350 cells per microL, aciclovir delayed risk of CD4 cell counts falling to <350 cells per microL by 19% (0.81, 0.71-0.93, p=0.002)

INTERPRETATION

The role of suppression of herpes simplex virus type 2 in reduction of HIV-1 disease progression before initiation of antiretroviral therapy warrants consideration.

FUNDING

Bill & Melinda Gates Foundation.

Detailed characterization of T cell responses to herpes simplex virus-2 in immune seronegative persons

In 2003, we described a small cohort of subjects (n = 6) who possessed no detectable serum Abs to HSV-1 or HSV-2 and no clinical or virological evidence of mucosal HSV infection yet possessed consistently detectable HSV-specific T cell responses measured primarily by lymphoproliferative (LP) and CTL assays to whole HSV-2 Ag. We termed these persons immune seronegative (IS). This report characterizes the T cell responses in 22 IS subjects largely recruited from studies of HSV-seronegative subjects in ongoing sexual relationships with HSV-2-seropositive (HSV-2(+)) partners using pools of overlapping peptides spanning 16 immuno-prevalent HSV-2 proteins. Overall, 77% of IS subjects had HSV-specific LP responses, 85% had IFN-gamma ELISPOT responses to at least one HSV-2 peptide pool, and 55% had both LP and IFN-gamma ELISPOT responses. In some cases, IFN-gamma ELISPOT responses were in excess of 500 spot-forming cells per 10(6) PBMCs and persisted for over 5 y. Although HSV-2(+) subjects (n = 40) had frequent responses to glycoproteins and tegument and immediate-early (IE) proteins of HSV-2, T cell responses in IS subjects were directed primarily at UL39 and the IE proteins ICP4 and ICP0. These data suggest that the antigenic repertoire of T cells in IS subjects is skewed compared with that of HSV-2(+) subjects and that IS subjects had more frequent T cell responses to IE proteins and infrequent T cell responses to virion components. Understanding the mechanism(s) by which such responses are elicited may provide important insights in developing novel strategies for preventing acquisition of sexually acquired HSV-2.

Acyclovir and transmission of HIV-1 from persons infected with HIV-1 and HSV-2

BACKGROUND

Most persons who are infected with human immunodeficiency virus type 1 (HIV-1) are also infected with herpes simplex virus type 2 (HSV-2), which is frequently reactivated and is associated with increased plasma and genital levels of HIV-1. Therapy to suppress HSV-2 reduces the frequency of reactivation of HSV-2 as well as HIV-1 levels, suggesting that suppression of HSV-2 may reduce the risk of transmission of HIV-1.

METHODS

We conducted a randomized, placebo-controlled trial of suppressive therapy for HSV-2 (acyclovir at a dose of 400 mg orally twice daily) in couples in which only one of the partners was seropositive for HIV-1 (CD4 count, > or = 250 cells per cubic millimeter) and that partner was also infected with HSV-2 and was not taking antiretroviral therapy at the time of enrollment. The primary end point was transmission of HIV-1 to the partner who was not initially infected with HIV-1; linkage of transmissions was assessed by means of genetic sequencing of viruses.

RESULTS

A total of 3408 couples were enrolled at 14 sites in Africa. Of the partners who were infected with HIV-1, 68% were women, and the baseline median CD4 count was 462 cells per cubic millimeter. Of 132 HIV-1 seroconversions that occurred after randomization (an incidence of 2.7 per 100 person-years), 84 were linked within couples by viral sequencing: 41 in the acyclovir group and 43 in the placebo group (hazard ratio with acyclovir, 0.92, 95% confidence interval [CI], 0.60 to 1.41; P=0.69). Suppression with acyclovir reduced the mean plasma concentration of HIV-1 by 0.25 log(10) copies per milliliter (95% CI, 0.22 to 0.29; P<0.001) and the occurrence of HSV-2-positive genital ulcers by 73% (risk ratio, 0.27; 95% CI, 0.20 to 0.36; P<0.001). A total of 92% of the partners infected with HIV-1 and 84% of the partners not infected with HIV-1 remained in the study for 24 months. The level of adherence to the dispensed study drug was 96%. No serious adverse events related to acyclovir were observed.

CONCLUSIONS

Daily acyclovir therapy did not reduce the risk of transmission of HIV-1, despite a reduction in plasma HIV-1 RNA of 0.25 log(10) copies per milliliter and a 73% reduction in the occurrence of genital ulcers due to HSV-2. (ClinicalTrials.gov number, NCT00194519.)

A pooled analysis of the effect of condoms in preventing HSV-2 acquisition

BACKGROUND

The degree of effectiveness of condom use in preventing the transmission of herpes simplex virus 2 (HSV-2) is uncertain. To address this issue, we performed a large pooled analysis.

METHODS

We identified prospective studies with individual-level condom use data and laboratory-defined HSV-2 acquisition. Six studies were identified through a review of publications through 2007: 3 candidate HSV-2 vaccine studies, an HSV-2 drug study, an observational sexually transmitted infection (STI) incidence study, and a behavioral STI intervention study. Study investigators provided us individual-level data to perform a pooled analysis. Effect of condom use was modeled using a continuous percentage of sex acts during which a condom was used and, alternatively, using absolute numbers of unprotected sex acts.

RESULTS

A total of 5384 HSV-2-negative people at baseline contributed 2 040 894 follow-up days; 415 persons acquired laboratory-documented HSV-2 during follow-up. Consistent condom users (used 100% of the time) had a 30% lower risk of HSV-2 acquisition compared with those who never used condoms (hazard ratio [HR], 0.70; 95% confidence interval [CI], 0.40-0.94) (P = .01). Risk for HSV-2 acquisition increased steadily and significantly with each unprotected sex act (HR, 1.16; 95% CI, 1.08-1.25) (P < .001). Condom effectiveness did not vary by gender.

CONCLUSIONS

To our knowledge, this is the largest analysis using prospective data to assess the effect of condom use in preventing HSV-2 acquisition. Although the magnitude of protection was not as large as has been observed with other STIs, we found that condoms offer moderate protection against HSV-2 acquisition in men and women.

Use of the designation "shedder" in mucosal detection of herpes simplex virus DNA involving repeated sampling

OBJECTIVES

We evaluated two methods to describe detection of herpes simplex virus (HSV) from the genital mucosa.

METHODS

We assessed genital swabs from HSV-2 seropositive people participating in longitudinal studies of HSV DNA detection at the University of Washington Virology Research Clinic. We determined the length of observation period necessary to ensure some HSV detection for most individuals. We compared two measures to assess differences in shedding according to HIV status, the shedding rate ratio, defined as the proportion of total samples with detectable HSV in HIV-1 seropositive versus HIV-1 seronegative participant, and the ratio of "shedders", defined as the proportion of people with any shedding over the interval in HIV-1 seropositive versus HIV-1 seronegative people.

RESULTS

While only 17% (51/308) of HSV-2 seropositive people shed on their first day on study, 77% (238/308) had some genital shedding over 30 days (any HSV DNA detected on genital swabs). Shedding rate ratios (SRR) for HIV-seropositive versus HIV-seronegative people varied from SRR = 1.42 using 10 samples to SRR = 1.35 using 50 samples. The ratio of "shedders" (RS) approached 1 as the observation period increased (RS = 1.13 using 10 samples to RS = 1.01 using 50 samples). In a hypothetical case, the ratio of "shedders" was shown to exceed 1 when shedding rates were equal.

CONCLUSIONS

Most HSV-2 seropositive people shed HSV from the genital mucosa. Dichotomisation of people into "shedders" and "non-shedders" or "high" and "low" shedders yields inferences that depend upon sampling interval length. Overall shedding rates provide consistent measures regardless of the number of swabs collected.

Incorporating validation subsets into discrete proportional hazards models for mismeasured outcomes

Standard proportional hazards methods are inappropriate for mismeasured outcomes. Previous work has shown that outcome mismeasurement can bias estimation of hazard ratios for covariates. We previously developed an adjusted proportional hazards method that can produce accurate hazard ratio estimates when outcome measurement is either non-sensitive or non-specific. That method requires that mismeasurement rates (the sensitivity and specificity of the diagnostic test) are known. Here, we develop an approach to handle unknown mismeasurement rates. We consider the case where the true failure status is known for a subset of subjects (the validation set) until the time of observed failure or censoring. Five methods of handling these mismeasured outcomes are described and compared. The first method uses only subjects on whom complete data are available (validation subset), whereas the second method uses only mismeasured outcomes (naive method). Three other methods include available data from both validated and non-validated subjects. Through simulation, we show that inclusion of the non-validated subjects can improve efficiency relative to use of the complete case data only and that inclusion of some true outcomes (the validation subset) can reduce bias relative to use of mismeasured outcomes only. We also compare the performance of the validation methods proposed using an example data set.

Rapidly cleared episodes of herpes simplex virus reactivation in immunocompetent adults

BACKGROUND

Herpes simplex virus (HSV) remains latent in nerve root ganglia of infected persons and is thought to reactivate several times yearly. Recent in situ data show the localization of HSV-specific CD8(+) T cells at the dermal epidermal junction next to peripheral sensory nerve endings, suggesting that viral reactivation may occur more frequently than previously appreciated.

METHODS

Twenty-five HSV-2-seropositive and 18 HSV-1-seropositive healthy adults collected anogenital and oral swabs, respectively, 4 times per day for 60 days. Swabs were assayed for HSV, using a quantitative polymerase chain reaction assay.

RESULTS

Twenty-four percent of anogenital reactivations and 21% of oral reactivations lasted < or =6 h, and 49% of anogenital reactivations and 39% of oral reactivations lasted < or =12 h. Lesions were reported in only 3 (7%) of 44 anogenital reactivations and 1 (8%) of 13 oral reactivations lasting < or =12 h. The median HSV DNA levels at initial and last detection were 10(3.5) and 10(3.3) copies/mL, respectively, during anogenital reactivation and 10(3.7) and 10(3.0) copies/mL, respectively, during oral reactivation.

CONCLUSIONS

This high frequency of short subclinical HSV reactivation in immunocompetent hosts strongly suggests that the peripheral mucosal immune system plays a critical role in clearing HSV reactivations.

Placebo found equivalent to amoxicillin for treatment of acute bronchitis in Nairobi, Kenya: a triple blind, randomised, equivalence trial

BACKGROUND

Antibiotic treatment is not recommended for acute bronchitis in immunocompetent patients in industrialised countries. Whether these recommendations are relevant to the developing world and to immunocompromised patients is unknown.

DESIGN, SETTING AND PARTICIPANTS

Randomised, triple blind, placebo controlled equivalence trial of amoxicillin compared with placebo in 660 adults presenting to two outpatient clinics in Nairobi, Kenya, with acute bronchitis but without evidence of chronic lung disease.

MAIN OUTCOME MEASURE

The primary study end point was clinical cure, as defined by a >or=75% reduction in a validated Acute Bronchitis Severity Score by 14 days; analysis was by intention to treat with equivalence defined as <or=8% difference between study arms.

RESULTS

Clinical cure rates in the amoxicillin and placebo arms were 81.7% and 84.0%, respectively (difference 2.3%, 95% CI -8.6% to 4.0%). Of 131 HIV infected subjects (19.8%), cure rates for those randomised to amoxicillin (77.2%) and placebo (83.8%) differed by 6.6% (95% CI -21.7% to 8.6%). Among HIV uninfected subjects, the difference in cure rates was 1.6% (95% CI -8.5% to 5.3%). Potential drug side effects were similar in the two arms. No subjects required hospitalisation or died.

CONCLUSION

Antibiotic treatment of acute bronchitis is unhelpful, even in populations with a high prevalence of HIV infection.

Genital herpes has played a more important role than any other sexually transmitted infection in driving HIV prevalence in Africa

Background

Extensive evidence from observational studies suggests a role for genital herpes in the HIV epidemic. A number of herpes vaccines are under development and several trials of the efficacy of HSV-2 treatment with acyclovir in reducing HIV acquisition, transmission, and disease progression have just reported their results or will report their results in the next year. The potential impact of these interventions requires a quantitative assessment of the magnitude of the synergy between HIV and HSV-2 at the population level.

Methods and Findings

A deterministic compartmental model of HIV and HSV-2 dynamics and interactions was constructed. The nature of the epidemiologic synergy was explored qualitatively and quantitatively and compared to other sexually transmitted infections (STIs). The results suggest a more substantial role for HSV-2 in fueling HIV spread in sub-Saharan Africa than other STIs. We estimate that in settings of high HSV-2 prevalence, such as Kisumu, Kenya, more than a quarter of incident HIV infections may have been attributed directly to HSV-2. HSV-2 has also contributed considerably to the onward transmission of HIV by increasing the pool of HIV positive persons in the population and may explain one-third of the differential HIV prevalence among the cities of the Four City study. Conversely, we estimate that HIV had only a small net impact on HSV-2 prevalence.

Conclusions

HSV-2 role as a biological cofactor in HIV acquisition and transmission may have contributed substantially to HIV particularly by facilitating HIV spread among the low-risk population with stable long-term sexual partnerships. This finding suggests that prevention of HSV-2 infection through a prophylactic vaccine may be an effective intervention both in nascent epidemics with high HIV incidence in the high risk groups, and in established epidemics where a large portion of HIV transmission occurs in stable partnerships.

Herpes simplex virus (HSV) suppression with valacyclovir reduces rectal and blood plasma HIV-1 levels in HIV-1/HSV-2-seropositive men: a randomized, double-blind, placebo-controlled crossover trial

BACKGROUND

Herpes simplex virus type 2 (HSV-2) infection is common among human immunodeficiency virus (HIV)-infected persons, and HSV reactivation increases plasma and genital HIV-1 levels. We studied HIV-1 levels during HSV suppression in coinfected persons in a placebo-controlled crossover trial.

METHODS

Twenty antiretroviral therapy (ART)-naive HIV-1/HSV-2-seropositive men who have sex with men in Lima, Peru, with CD4 cell counts >200 cells/ microL were randomized to receive either valacyclovir at 500 mg twice daily or placebo for 8 weeks, after which they underwent a 2-week washout period and then received the alternative regimen for 8 weeks. Specimens included daily anogenital swabs (for HSV DNA polymerase chain reaction [PCR]), thrice weekly rectal mucosal secretions (for HIV-1 RNA and HSV DNA PCR) obtained by anoscopy, and weekly plasma (for HIV-1 RNA PCR). Outcomes were rectal and plasma HIV-1 RNA levels by treatment arm.

RESULTS

HIV-1 was detected in 73% of 844 rectal and 99% of 288 plasma specimens. HSV was detected in 29% and 4% of mucocutaneous specimens obtained during placebo and valacyclovir administration, respectively (P<.001). Valacyclovir resulted in a 0.16 (95% confidence interval [CI], 0.07-0.25; P=.0008; 33% decrease) log(10) copies/mL lower mean within-subject rectal HIV-1 level and a 0.33 (95% CI, 0.23-0.42; P<.0001; 53% decrease) log(10) copies/mL lower plasma HIV-1 level, compared with values for placebo.

CONCLUSIONS

Valacyclovir significantly reduces rectal and plasma HIV-1 levels in HIV-1/HSV-2-coinfected men. HSV suppression may provide clinical benefits to persons not receiving highly active ART as well as public health benefits.

Polymorphisms in TLR2 are associated with increased viral shedding and lesional rate in patients with genital herpes simplex virus Type 2 infection

Clinical and virologic manifestations of genital herpes simplex virus type 2 (HSV-2) infection vary widely. We examined frequencies of single-nucleotide polymorphisms (SNPs) in Toll-like receptors (TLRs) 2, 3, 4, and 9 in a prospective cohort of 128 HSV-2-infected persons whose viral shedding and lesion frequency was measured by daily sampling from genital secretions. Two TLR2 haplotypes (2 and 4) were associated with increased lesional (P=.008 and P=.03) and shedding (P=.02 and P=.001) rates. An SNP in haplotype 2 (-15607A/G) was also associated with shedding (P=.01) and lesional (P=.008) rates. Polymorphisms in TLR2 may be in part responsible for differences in the severity of HSV-2 infection.

Topical resiquimod 0.01% gel decreases herpes simplex virus type 2 genital shedding: a randomized, controlled trial

BACKGROUND

Resiquimod, an investigational immune response modifier and Toll-like receptor (TLR) 7 and 8 agonist, stimulates production of cytokines that promote an antigen-specific T helper type 1 (Th1)--acquired immune response. In animal models, induction of Th1-specific responses modifies experimental herpes simplex virus (HSV) infection.

METHODS

We conducted a randomized, double-blind, vehicle-controlled trial to assess the efficacy of resiquimod 0.01% gel for reducing human anogenital HSV-2 mucosal reactivation. Adults with genital HSV-2 applied resiquimod or vehicle topically to herpes lesions 2 times weekly for 3 weeks and then collected daily anogenital swabs for 60 days for HSV DNA polymerase chain reaction. Recurrences during the subsequent 7 months were treated with study gel. During the final treatment-free 60 days, participants again collected daily swabs to assess shedding.

RESULTS

The median lesion and shedding rates were lower for resiquimod compared with vehicle recipients during the initial sampling period (10% vs. 16% [P=.03] and 10% vs. 17% [P=.08], respectively) and during the final sampling period (3% vs. 22% [P<.001] and 10% vs. 26% [P=.009], respectively). Resiquimod did not influence recurrence length.

CONCLUSIONS

These findings suggest that the immunological control of HSV-2 reactivation and lesion clearance may differ and that TLR7 and TLR8 agonists can reduce the frequency of mucosal HSV-2 reactivation.

Optimizing PCR positivity criterion for detection of herpes simplex virus DNA on skin and mucosa

In 1997, we developed a PCR assay for the detection of herpes simplex virus (HSV) DNA. Recently, we determined an optimal positivity criterion based on research specimens and a dilution study. We found that a cutoff of 50 HSV DNA copies/ml of swab specimen, a level 10-fold lower than our previous cutoff, minimizes misclassification.

Family saliva sharing behaviors and age of human herpesvirus-6B infection

OBJECTIVE

Transmission of human herpesvirus (HHV-6) type B is hypothesized to occur via saliva. We sought to determine whether behaviors promoting saliva sharing were associated with HHV-6B infection.

METHODS

Parents of young children participating in a natural history study of HHV-6B were asked to complete a questionnaire focused on family behaviors that result in saliva sharing.

RESULTS

Of 111 surveys, 109 (98%) were completed. Of the 109 participants, 37 (34%) were infected with HHV-6 before 1 year of age. Having older siblings (adjusted OR 4.1, 95% CI 1.5, 11.8) and receipt of parental saliva when kissed (adjusted OR 5.1, 95% CI 1.8, 14.5) were independently associated with younger age of HHV-6 infection. Dose-response relationships were demonstrated between HHV-6 infection before 1 year and both number of siblings and the frequency that the child received parental saliva when being kissed (p=0.006 and p=0.002, respectively).

CONCLUSIONS

Having older siblings and parents who shared saliva increased risk of HHV-6B acquisition in children. These data support the hypothesis that HHV-6 is transmitted primarily via saliva within families.