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The aim of this study was to examine the cost-effectiveness of adding nucleic acid testing (NAT) to serological (antibody and antigen) screening protocols for donated blood in the United States (US) with the purpose of reducing the risks of transfusion-transmission of hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV). The costs, health consequences and cost-effectiveness of adding either minipool or individual-donor NAT to serological screening (SS) testing were estimated using a decision-analysis model. With the given modelling assumptions, adding minipool NAT would avoid an estimated 37, 128 and eight cases of HBV, HCV and HIV, respectively, and save ≈ 53 additional years of life and 102 additional quality adjusted life years (QALYs) compared with SS, at a net cost of $154 million. SS + minipool NAT − p24 compared with SS alone resulted in an incremental cost-effectiveness ratio of $1·5 million per QALY gained (range in sensitivity analysis $1·0–2·1 million per QALY gained) in this US analysis. The cost effectiveness of adding NAT screening is outside the typical range for most healthcare interventions, but not for established blood safety measures. [ABSTRACT FROM AUTHOR]

Over 70 million individuals are infected with hepatitis C virus (HCV) worldwide. Yet most prevalence data are in the adult population, with little focus on paediatrics, partially due to the scarcity of public data. The objective of this paper is to examine HCV prevalence in children by estimating prevalence rates among women, given the assumption that most cases are vertically transmitted. Between 2001 and 2017, maternal HCV infection affected ~ 0.24% of all births, with prevalence increasing by at least 261%. On average, approximately 0.01% of the total number of live births were infected with HCV, with a 245% increase in the number of children born with the infection. HCV epidemiology has evolved, with women of childbearing age representing a greater proportion of infected individuals in the United States, and infants born to infected mothers being at risk. We therefore recommend a greater public health focus of HCV on the paediatric population. [ABSTRACT FROM AUTHOR]

The therapeutic landscape for the treatment of chronic hepatitis C virus infection has been rapidly evolving, and by 2016 there will be six approved, all-oral regimens for use in patients in the USA and most of Western Europe. However, as many as patient populations will have limited access to new direct acting antiviral regimens, patients and physicians are often faced with the challenge of selecting the best regimen available, as opposed to the optimal treatment. In this paper, the challenges and opportunities in developing a high cure regimen for different patient populations will be discussed and highlighted through case-based scenarios. [ABSTRACT FROM AUTHOR]

Chronic hepatitis C virus is one of the leading causes of liver diseases in adults and it is the most common cause of liver transplantation in the USA. Hepatitis C infection in children is less frequent; there is less information about its clinical course. Compared with adults, there are differences in its mode of acquisition, natural history, complications and even available treatments. The aim of this paper is to give an overview of chronic hepatitis C in children. [ABSTRACT FROM AUTHOR]

This paper considers the literature relating to the course of hepatitis C infection and its implications for those with haemophilia. It goes on to discuss a model that assessed the economic aspects of treating hepatitis C cases with interferon-α, discusses recent changes in recommended treatment of hepatitis C and critically reviews the model and its application to patients with haemophilia. [ABSTRACT FROM AUTHOR]

Background: Trends in the prevalence of hepatitis C virus (HCV) infection among women delivering live births may differ in rural vs. urban areas of the United States, but estimation of trends based on observed counts may lead to unstable estimates in rural counties due to small numbers. Objectives: The objective of the study was to use small area estimation methods to provide updated county‐level prevalence estimates and, for the first time, trends in maternal HCV infection among live births by county‐level rurality. Methods: Cross‐sectional natality data from 2016 to 2020 were used to estimate maternal hepatitis C prevalence using hierarchical Bayesian models with spatiotemporal random effects to produce annual county‐level estimates of maternal HCV infection and trends over time. Models included a 6‐level rural–urban county classification, year, maternal characteristics and county‐specific covariates. Data were analysed in 2022. Results: There were 90,764/18,905,314 live births (4.8 per 1000) with HCV infection reported on the birth certificate. Hepatitis C prevalence was higher among rural counties as compared to urban counties. Rural counties had the largest annual increases in maternal hepatitis C prevalence (per 1000 births) from 2016 to 2020 (micropolitan: 0.39; noncore: 0.40), with smaller increases among less densely populated urban counties (medium metro: 0.28; small metro: 0.28) and urban counties (large central metro:0.11; large fringe metro: 0.14). Conclusions: The prevalence of maternal HCV infection was the highest in rural counties, and rural counties saw the greatest average prevalence increase during 2016–2020. County‐level data can help in monitoring rural–urban trends in maternal HCV infection to reduce geographic disparities. [ABSTRACT FROM AUTHOR]

Background: Blood‐borne viruses (BBVs) cause significant morbidity and mortality worldwide. Emergency departments (EDs) offer a point of contact for groups at increased risk of BBVs who may be less likely to engage with primary care. We reviewed the literature to evaluate whether BBV testing in this setting might be a viable option to increase case finding and linkage to care. Methods: We searched PubMed database for English language articles published until June 2019 on BBV testing in EDs. Studies reporting seroprevalence surveys, feasibility, linkage to care, enablers and barriers to testing were included. Additional searches for grey literature were performed. Results: Eight‐nine articles met inclusion criteria, of which 14 reported BBV seroprevalence surveys in EDs, 54 investigated feasibility and acceptability, and 36 investigated linkage to care. Most studies were HIV‐focused and conducted in the USA. Seroprevalence rates were in the range 1.5–17% for HCV, 0.7–1.6% for HBV, and 0.8–13% for HIV. For studies that used an opt‐in study design, testing uptake ranged from 2% to 98% and for opt‐out it ranged from 16% to 91%. There was a wide range of yield: 13–100% of patients received their test result, 21–100% were linked to care, and 50–91% were retained in care. Compared with individuals diagnosed with HIV, linkage to and retention in care were lower for those diagnosed with hepatitis C. Predictors of linkage to care was associated with certain patient characteristics. Conclusions: Universal opt‐out BBV testing in EDs may be feasible and acceptable, but linkage to care needs to be improved by optimizing implementation. Further economic evaluations of hepatitis testing in EDs are needed. [ABSTRACT FROM AUTHOR]

Introduction: Ageing patients with haemophilia (PWH) develop cardiovascular risk factors impacting care. Little is known about the prevalence of diabetes in PWH and its relation to other comorbidities. Aim: To examine the risk of diabetes for adult PWH compared to men from the general United States population (National Health and Nutrition Examination Surveys [NHANES]) and outpatients attending a Veterans Affairs Medical Center (VAMC) clinic. Methods: Retrospective cross‐sectional design. PWH from four haemophilia centres (n = 690) were matched with random samples from NHANES and VAMC. Diabetes (yes/no) was the outcome, while age, body mass index (BMI), race and Hepatitis C (HCV; by serology) and human immunodeficiency virus (HIV) positivity were covariates. We fitted semiparametric generalized additive models (GAMs) in order to compare diabetes risk between cohorts. Results: Younger PWH were at lower risk of diabetes than NHANES or VAMC subjects irrespective of BMI. However, the risk of diabetes rose in older PWH and was closely associated with HCV. For HCV‐negative subjects, the risk of diabetes was considerably lower for PWH than NHANES and VAMC subjects. The difference persisted after controlling for BMI and age, indicating that the low risk of diabetes in PWH cannot be explained by lean body mass alone. Conclusion: Since many ageing PWH are HCV positive and therefore at heightened risk for diabetes, it is important to incorporate diabetes screening into care algorithms in Haemophilia Treatment Centers, especially since PWH are not always followed in primary care clinics. [ABSTRACT FROM AUTHOR]

Organ procurement organizations (OPOs) evaluate referrals for deceased organ donation in the United States. Efforts to expand the donor pool, such as the HIV organ policy equity (HOPE) Act that permits transplants from HIV‐positive donors to HIV‐positive recipients, can only succeed if OPOs pursue referrals. However, relatively little is known about how OPO staff evaluate referrals. To better understand this process, OPO staff completed a discrete choice experiment to quantify the relative importance of seven donor characteristics on the decision to pursue a theoretical donor. Relative importance was defined by Partworth utility using a hierarchical Bayesian conditional logit model. There were 51 respondents from 36 of 58 OPOs in the United States. Of the seven attributes, organ and tissue potential were the most influential, followed by age, type of death, HIV status, donor registration, and Hepatitis C status. To be preferred to an HIV‐negative donor, an HIV‐positive donor needed to have the potential to donate two additional organs. These data provide insight into the preferences of OPO referral staff and may help explain the lower than expected number of HIV‐positive transplants performed since the passage of the HOPE Act. [ABSTRACT FROM AUTHOR]

Background and Aims: Injection drug use has increased in non‐urban communities in the United States where sterile syringe access is limited. This study aimed to characterize how people who inject drugs in a predominantly rural state navigate syringe scarcity. Design Qualitative study. Setting New Hampshire (NH), USA. At the time of our study, syringe services programs were illegal in NH but pharmacies could sell ≤ 10 syringes without prescription. Participants/Cases: Twenty people aged ≥ 18 years who injected at least once in the past 30 days were recruited through provider referral, street‐based recruitment and snowball sampling. Measurements Semi‐structured interview guide. Verbatim transcripts were coded based on interview guide constructs and emergent themes. Analysis focused on pharmacy syringe access, unofficial syringe sources and related impacts on syringe sharing and reuse Findings Participants could identify no local pharmacies that sold syringes without prescription. Pharmacy purchase in neighboring counties, or across state lines, required private transportation and this, along with purchaser identification requirements, presented substantial access barriers. Interstate travel also exposed participants to vigilant policing of interstate highways and potential criminal justice involvement. Many participants thus resorted to informal syringe sources closer to home including purchasing syringes on the street, using discarded syringes, breaking into biohazard containers and constructing improvised syringes out of salvaged syringe parts, metals and plastics. Repeated re‐use of syringes until they were no longer operational was common. Overall, syringe scarcity gave participants few options but to engage in syringe sharing and re‐use, putting them at risk of serious injection‐related infections. Conclusions: Limited sterile syringe access contributes to an environment in which people who inject drugs report that they are less able to refrain from risky injection practices. [ABSTRACT FROM AUTHOR]

Summary: Background: Direct‐acting anti‐virals (DAA) are highly effective for hepatitis C virus (HCV) treatment, but perceived risks of medication non‐adherence may restrict access to care. Digital medicine programme (DMP) has improved adherence and outcomes for some conditions. Aims: To conduct a prospective, single‐arm, open‐label study across the United States to assess the impact of DMP on adherence and efficacy in adults with chronic HCV infection at high risk for non‐adherence. Methods: Eligible participants were placed on the DMP to evaluate real‐time adherence; primary outcome was sustained virological response (SVR) at ≥10 weeks post‐treatment. Results: Between August 2017 and April 2019, 288 participants (Medicaid, 64.9%; psychiatric disorders, 61.1%; homeless, 9.4%) received DAAs for 8‐12 weeks (sofosbuvir/velpatasvir or ledipasvir, 45%; glecaprevir/pibrentasvir, 55%). SVR was achieved in 99.1% of 218 participants who had HCV RNA assessed at ≥10 weeks post‐treatment; of the 70 participants who did not have SVR assessed, 17 had SVR4 with HCV RNA assessed at a median (IQR; interquartile range) 5.6 weeks (4.1, 7.9) post‐treatment; one completed treatment but did not have HCV RNA assessed, and 52 discontinued treatment early without assessment. Overall, the primary analysed participants (n = 218) actively used the DMP for median (range) 92.9% (12.5%, 100%) of their prescribed treatment time, and overall pill‐taking adherence was 95.0% (57.1%, 100%). Participants reported the programme was useful and easy to use through satisfaction surveys. Conclusions: HCV treatment with DMP was accepted by patients and clinicians and may support HCV treatment outcomes among patients at high risk for treatment non‐adherence (Clinical trials.gov NCT03164902). [ABSTRACT FROM AUTHOR]

Chronic hepatitis C (CHC) is the most common cause of infection related deaths in USA according to Central Disease Control and Prevention (CDC) report in 2016. Hepatitis C is a blood borne virus and is common in chronic kidney disease (CKD) and in hemodialysis (HD) dependent patients. A majority of patients with CHC could remain asymptomatic and are still undiagnosed. Early detection of CHC and linkage of infected patients to care for evaluation and treatment is the standard of care as emphasized by Kidney Disease Improving Global Outcome (KDIGO) and American Association for the Study of Liver Disease- Infectious Disease Society of America (AASLD-IDSA) practice guidelines. Historically, the management of hepatitis C virus (HCV)-infected CKD patients, including those on dialysis and in the peri-transplant setting, was a challenge. However, the evolution of various liver assessment tools, HCV tests, therapies and treatment strategies in the recent years has catalyzed a paradigm change in this area. This review provides an update on evaluating methodology, diagnostic tests and the various assessment tools for liver fibrosis pertaining to the CKD/HD patient infected with HCV. [ABSTRACT FROM AUTHOR]

Background and aims Effective strategies are needed to address dramatic increases in hepatitis C virus (HCV) infection among people who inject drugs (PWID) in rural settings of the United States. We determined the required scale-up of HCV treatment with or without scale-up of HCV prevention interventions to achieve a 90% reduction in HCV chronic prevalence or incidence by 2025 and 2030 in a rural US setting. Design An ordinary differential equation model of HCV transmission calibrated to HCV epidemiological data obtained primarily from an HIV outbreak investigation in Indiana. Setting Scott County, Indiana (population 24 181), USA, a rural setting with negligible baseline interventions, increasing HCV epidemic since 2010, and 55.3% chronic HCV prevalence among PWID in 2015. Participants PWID. Measurements Required annual HCV treatments per 1000 PWID (and initial annual percentage of infections treated) to achieve a 90% reduction in HCV chronic prevalence or incidence by 2025/30, either with or without scaling-up syringe service programmes (SSPs) and medication-assisted treatment (MAT) to 50% coverage. Sensitivity analyses considered whether this impact could be achieved without re-treatment of re-infections, and whether greater intervention scale-up was required due to the increasing epidemic in this setting. Findings To achieve a 90% reduction in incidence and prevalence by 2030, without MAT and SSP scale-up, 159 per 1000 PWID (initially 24.9% of infected PWID) need to be HCV-treated annually. However, with MAT and SSP scaled-up, treatment rates are halved (89 per 1000 annually or 14.5%). To reach the same target by 2025 with MAT and SSP scaled-up, 121 per 1000 PWID (19.9%) need treatment annually. These treatment requirements are threefold higher than if the epidemic was stable, and the impact targets are unattainable without retreatment. Conclusions Combined scale-up of hepatitis C virus treatment and prevention interventions is needed to decrease the increasing burden of hepatitis C virus incidence and prevalence in rural Indiana, USA, by 90% by 2025/30. [ABSTRACT FROM AUTHOR]

Discusses the abstract of the research paper 'Validation of Transcription Mediated Assay for HIV-1 and HCV Screening with Eight Specimen Mini-Pools,' by P. Ghiazza, et al, to be presented at the American Association of Blood Banks' 55th Annual Meeting on October 26-29, 2002.

Objective To develop a new evidence-based, pharmacologic treatment guideline for rheumatoid arthritis (RA). Methods We conducted systematic reviews to synthesize the evidence for the benefits and harms of various treatment options. We used the Grading of Recommendations Assessment, Development and Evaluation (GRADE) methodology to rate the quality of evidence. We employed a group consensus process to grade the strength of recommendations (either strong or conditional). A strong recommendation indicates that clinicians are certain that the benefits of an intervention far outweigh the harms (or vice versa). A conditional recommendation denotes uncertainty over the balance of benefits and harms and/or more significant variability in patient values and preferences. Results The guideline covers the use of traditional disease-modifying antirheumatic drugs (DMARDs), biologic agents, tofacitinib, and glucocorticoids in early (<6 months) and established (≥6 months) RA. In addition, it provides recommendations on using a treat-to-target approach, tapering and discontinuing medications, and the use of biologic agents and DMARDs in patients with hepatitis, congestive heart failure, malignancy, and serious infections. The guideline addresses the use of vaccines in patients starting/receiving DMARDs or biologic agents, screening for tuberculosis in patients starting/receiving biologic agents or tofacitinib, and laboratory monitoring for traditional DMARDs. The guideline includes 74 recommendations: 23% are strong and 77% are conditional. Conclusion This RA guideline should serve as a tool for clinicians and patients (our two target audiences) for pharmacologic treatment decisions in commonly encountered clinical situations. These recommendations are not prescriptive, and the treatment decisions should be made by physicians and patients through a shared decision-making process taking into account patients' values, preferences, and comorbidities. These recommendations should not be used to limit or deny access to therapies. [ABSTRACT FROM AUTHOR]

Hepatitis C is the leading indication for liver transplantation in the USA and recurrence is universal. The impact of preexisting diabetes, new-onset diabetes after transplant (NODAT), and glycemic control on fibrosis progression has not been studied. This retrospective longitudinal cohort study included adult liver recipients with hepatitis C transplanted between 2000 and 2011. Patients were divided into three groups: preexisting diabetes (n = 41), NODAT (n = 59), and no diabetes (n = 103). Patients with preexisting diabetes (70%) or NODAT (59%) were more likely to develop hepatitis C recurrence (≥stage 1 fibrosis), as compared to non-diabetics (36%, p = 0.006). There was also a trend toward a higher incidence of at least Stage 2 fibrosis (36% and 48% vs. 23%, respectively; p = 0.063). Patients with tight glycemic control had a lower rate of Stage 2 fibrosis development (78% vs. 60%, p = 0.027), while those with good control (<150 mg/ dL) also had lower rates of Stage 2 fibrosis (84% vs. 62%, p = 0.004). Multivariable analysis verified a decreased rate of recurrence for patients with blood glucose <138 mg/ dL (p = 0.021), after controlling for confounders. These results demonstrate that diabetes is strongly associated with an increased risk of hepatitis C virus-related fibrosis development and glycemic control may reduce the risk and severity of recurrence. [ABSTRACT FROM AUTHOR]

Infection with hepatitis C virus is the most common indication for liver transplantation in the United States. Although recurrence of hepatitis C virus infection is universal following transplantation, the natural history of posttransplantation hepatitis C varies. In general, however, posttransplant hepatitis C virus infection progresses relatively quickly, with 10%-20% of patients developing cirrhosis within 5 years. Risk factors for severe recurrent hepatitis C include donor age, female sex, treatment of rejection, preservation injury, and high viral load pretransplant or early posttransplant. Type of allograft, infection with cytomegalovirus, or type of calcineurin inhibitor used may not play a role. Treatment with interferon + ribavirin in recurrent hepatitis C virus shows mixed results. Sustained virologic response has been observed in only 8%-30% of patients, and side effects of these medications are considerable. Protease inhibitors are not yet approved for the posttransplant population, but clinical trials are under way. Mt Sinai J Med 79:190-198, 2012. © 2012 Mount Sinai School of Medicine [ABSTRACT FROM AUTHOR]

The purpose of the present investigation is to provide an analysis of previous works on the epidemiology of the hepatitis C virus (HCV) infection from six countries throughout Latin America, to forecast the future HCV prevalence trends in Argentina, Brazil, Mexico and Puerto Rico, and to outline deficiencies in available data, highlighting the need for further research. Data references were identified through indexed journals and non-indexed sources. Overall, 1080 articles were reviewed and 150 were selected based on their relevance to this work. When multiple data sources were available for a key assumption, a systematic process using multi-objective decision analysis (MODA) was used to select the most appropriate sources. When data were missing, analogues were used. Data from other countries with similar risk factors and/or population compositions were used as a proxy to help predict the future trends in prevalence. The review indicates that the dominant genotype is type 1. HCV prevalence in the analysed countries ranges from 1 to 2.3%. The Latin American countries have been very proactive in screening their blood supplies, thus minimizing the risk of transmission through transfusion. This suggests that other risk factors are set to play a major role in continued new infections. The number of diagnosed and treated patients is low, thereby increasing the burden of complications such as liver cirrhosis or hepatocellular carcinoma. The HCV prevalence, according to our modelling is steady or increasing and the number of infected individuals will increase. The results herein reported should provide a foundation for informed planning efforts to tackle hepatitis. [ABSTRACT FROM AUTHOR]

Hispanics have much higher cirrhosis mortality rates than non-Hispanic Blacks and Whites. Although heavy alcohol use and hepatitis C virus (HCV) infection are two major risk factors for cirrhosis, no studies have systematically assessed the contribution of alcohol- and HCV-related cirrhosis deaths to the total cirrhosis mortality for Hispanics as a whole and its variations across Hispanic subgroups. To fill this gap, this study presents the latest data on total cirrhosis mortality as well as its component alcohol- and HCV-related cirrhosis mortality for all Hispanics and for Hispanic subgroups. The multiple-cause approach was used to analyze data from the U.S. Multiple Cause of Death Data Files for 28,432 Hispanics and 168,856 non-Hispanic Whites (as a comparison group) who died from cirrhosis as the underlying or a contributing cause during 2000-2004. Four major Hispanic subgroups were defined by national origin or ancestry, including Mexicans, Puerto Ricans, Cubans, and Other Hispanics. The cirrhosis deaths were divided into four distinctive cause-of-death categories: alcohol-related, HCV-related, both alcohol- and HCV-related, and neither alcohol- nor HCV-related. Age-adjusted total cirrhosis death rates and percentage shares of the cause-specific categories were compared across Hispanic subgroups and non-Hispanic Whites. Compared with non-Hispanic Whites, all Hispanic subgroups except Cubans had much higher cirrhosis mortality. The age-adjusted total cirrhosis death rates were twice as high for Puerto Ricans and Mexicans as for non-Hispanic Whites. Alcohol-related and HCV-related cirrhosis death rates also were higher for most Hispanic subgroups than for non-Hispanic Whites. Heavy alcohol use and hepatitis C viral infection are two important factors contributing to the high cirrhosis mortality among Hispanics. However, their relative contributions to total cirrhosis mortality varied by gender and Hispanic subgroup. This information is useful for targeted prevention and intervention efforts to address the excessive cirrhosis mortality in the Hispanic population. [ABSTRACT FROM AUTHOR]

Chronic hepatitis C affects 170 million people worldwide, including up to 4 million people in the United States. The current standard of care therapy with pegylated interferon (PEG-IFN) and ribavirin (RBV) while highly successful in patients with genotype 2 and 3 infection, allows for sustained virologic response in 42–46% of treatment-naïve genotype 1 patients, comprising about 70% of cases of chronic hepatitis C in the USA. While awaiting approval of Specifically Targeted Antiviral Therapy for HCV (STAT-C) agents, which will require the completion of additional clinical trials, it is important to optimize the dose and duration of currently available treatment modalities, namely PEG-IFN and RBV, for treatment of CHC. Results of several recent trials evaluating optimal dosing of RBV and higher than standard dosing of PEG-IFN in treatment-naïve genotype 1 patients, as well as data from retreatment trials with “induction” doses of PEG-IFN or high-dose RBV in prior non-responders to IFN-based therapy will be reviewed here. The possibility of shorter duration of therapy for genotype 2 and 3 patients based on recent publications and presentations will be discussed as well. [ABSTRACT FROM AUTHOR]

Chronic hepatitis C virus (HCV) infection causes cirrhosis in many infected patients; however, a better understanding of the risk factors for fibrosis progression in high HCV prevalence groups such as US veterans is needed. We wished to compare the demographic, clinical characteristics, and independent variables that influence fibrosis in US veterans vs nonveterans with chronic HCV. HCV-seropositive US veterans ( n = 459) and nonveterans ( n = 395) prospectively completed a detailed medical, social and occupational questionnaire. Clinical factors for progressive liver disease were compared between veterans and nonveterans and fibrosis stage assessed on liver biopsies (168 veterans and 208 nonveterans). Using polychotomous logistic regression, fibrosis was analysed as both a progressive and categorical outcome to determine independent risk factors for both patient groups. Although veterans were significantly older and had higher lifetime alcohol consumption than nonveterans, their median fibrosis scores did not differ from nonveterans. By univariate analysis, alanine aminotransferase, necroinflammatory activity (NIA), and cryoglobulin positivity were associated with fibrosis in veterans and nonveterans ( P < 0.05, all comparisons), whereas steatosis was associated with fibrosis only in nonveterans ( P < 0.0001). By multivariate analysis, NIA was an independent risk factor for fibrosis in both groups ( P < 0.01). However, fibrosis in nonveterans was also independently associated with steatosis, significant alcohol consumption and age ( P < 0.04, all comparisons). Independent risk factors for fibrosis vary among high HCV prevalence groups such as veterans when compared with nonveterans. Understanding specific patient cohort effects is important for determining independent risk factors for disease progression in chronic HCV infection. [ABSTRACT FROM AUTHOR]

A commentary on the article "Cost‐effectiveness of scaling‐up HCV prevention and treatment in the United States for people who inject drugs," by C. Barbosa, H. Fraser, T.J. Leib, J.R. Havens and A. Young is presented.