Spontaneous viral clearance following acute hepatitis C infection: a systematic review of longitudinal studies

Hepatitis C virus double-stranded RNA is the predominant form in human liver and in interferon-treated cells

Hepatitis C virus (HCV) is unique among RNA viruses in its ability to establish chronic infection in the majority of exposed adults. HCV persists in the liver despite interferon (IFN)-stimulated gene (ISG) induction; robust induction actually predicts treatment failure and viral persistence. It is unclear which forms of HCV RNA are associated with ISG induction and IFN resistance during natural infections. To thoroughly delineate HCV RNA populations, we developed conditions that fully separate the strands of long double-stranded RNA (dsRNA) and allow the released RNAs to be quantified in reverse transcription/polymerase chain reaction assays. These methods revealed that dsRNA, a pathogen-associated molecular pattern (PAMP), comprised 52% (standard deviation, 28%) of the HCV RNA in the livers of patients with chronic infection. HCV dsRNA was proportionally higher in patients with the unfavorable IL28B TT (rs12979860) genotype. Higher ratios of HCV double-stranded to single-stranded RNA (ssRNA) correlated positively with ISG induction. In Huh-7.5 cells, IFN treatment increased the total amount of HCV dsRNA through a process that required de novo viral RNA synthesis and shifted the ratio of viral dsRNA/ssRNA in favor of dsRNA. This shift was blocked by ribavirin (RBV), an antiviral drug that reduces relapse in HCV patients. Northern blotting established that HCV dsRNA contained genome-length minus strands.

CONCLUSION

HCV dsRNA is the predominant form in the HCV-infected liver and has features of both a PAMP and a genomic reservoir. Interferon treatment increased rather than decreased HCV dsRNA. This unexpected finding suggests that HCV produces dsRNA in response to IFN, potentially to antagonize antiviral defenses. (Hepatology 2017;66:357-370).

Changing landscape of hepatitis C virus-positive donors

With the introduction of the new highly effective antiviral therapies, there has been a dramatic increase in the use of the hepatitis C virus (HCV)-positive livers in HCV-positive recipients. In the majority of studies, HCV positivity was defined as a donor testing HCV Ab positive. In 2015, all Organ Procurement Organizations were mandated to perform and report HCV Nucleic Acid Amplification Testing (NAT) results on all deceased and living donors. Studies are not yet available on how organs are being utilized based on NAT status and whether NAT status affects recipient outcomes. Further studies are needed to maximize the use of these organs.

MSM starting preexposure prophylaxis are at risk of hepatitis C virus infection

OBJECTIVES AND DESIGN

Hepatitis C virus (HCV) has been recognized as an emerging sexually transmitted infection (STI) among HIV-positive MSM. However, HIV-negative MSM at high risk for HIV might also be at increased risk for HCV. We studied the HCV prevalence in HIV-negative MSM who start preexposure prophylaxis (PrEP) in Amsterdam. Phylogenetic analysis was used to compare HCV strains obtained from HIV-negative and HIV-positive MSM.

METHODS

At enrolment in the Amsterdam PrEP demonstration project, HIV-negative MSM were tested for the presence of HCV antibodies and HCV RNA. If positive for HCV RNA, an HCV NS5B gene fragment (709 bp) was sequenced and compared with HCV isolates from HIV-positive MSM (n = 223) and risk groups other than MSM (n = 153), using phylogenetic analysis.

RESULTS

Of 375 HIV-negative MSM enrolled in Amsterdam PrEP, 18 (4.8%, 95% confidence interval 2.9-7.5%) of participants were anti-HCV and/or HCV RNA positive at enrolment; 15 of 18 (83%) had detectable HCV RNA. HCV genotyping showed genotype 1a (73%), 4d (20%), and 2b (7%). All HCV-positive MSM starting PrEP were part of MSM-specific HCV clusters containing MSM with and without HIV.

CONCLUSION

HCV prevalence among HIV-negative MSM who started PrEP was higher than previously reported. All HIV-negative HCV-positive MSM were infected with HCV strains already circulating among HIV-positive MSM. The increasing overlap between sexual networks of HIV-positive and HIV-negative MSM might result in an expanding HCV-epidemic irrespective of HIV-status. Hence, routine HCV testing should be offered to MSM at high risk for HIV, especially for those enrolling in PrEP programs.

Improving Screening Methods for Hepatitis C Among People Who Inject Drugs: Findings from the HepTLC Initiative, 2012-2014

OBJECTIVE

People who inject drugs (PWID) are at increased risk for hepatitis C virus (HCV) infection. We examined HCV testing outcomes among PWID through CDC's Hepatitis Testing and Linkage to Care initiative, which promoted viral hepatitis B and hepatitis C screening, posttest counseling, and linkage to care at 34 U.S. sites during 2012-2014. Ten grantees in nine geographically diverse cities conducted HCV testing among PWID.

METHODS

Among those testing positive for HCV antibody (anti-HCV), we calculated the proportion who were offered a confirmatory HCV ribonucleic acid (RNA) test, positively diagnosed, and referred to a specialist for care. We stratified anti-HCV-positive people who completed each step by same-day testing (i.e., an HCV RNA test administered on the same date as an anti-HCV test) vs. person not receiving same-day testing to evaluate whether the need for follow-up testing affected diagnosis of chronic infection and linkage to care.

RESULTS

A total of 15,274 people received an anti-HCV test at 84 testing sites targeting PWID. Of those, 11,159 (73%) reported having injected drugs in their lifetime, 7,789 (51%) reported injecting drugs in the past 12 months, and 3,495 (23%) tested anti-HCV positive. A total of 1,630 people received testing for HCV RNA, of whom 1,244 (76%) were HCV RNA positive. When not receiving both tests on the same day, 601 of 2,465 (24%) anti-HCV-positive people received an HCV RNA test.

CONCLUSION

Strategies to diagnose PWID for HCV infection are needed to reduce associated morbidity and mortality. Agencies can substantially increase the number of PWID who are diagnosed and informed of their HCV infection by administering both anti-HCV and HCV RNA tests during a single testing event.

Modelling the impact of incarceration and prison-based hepatitis C virus (HCV) treatment on HCV transmission among people who inject drugs in Scotland

BACKGROUND AND AIMS

People who inject drugs (PWID) experience high incarceration rates, and previous incarceration is associated with elevated hepatitis C virus (HCV) transmission risk. In Scotland, national survey data indicate lower HCV incidence in prison than the community (4.3 versus 7.3 per 100 person-years), but a 2.3-fold elevated transmission risk among recently released (< 6 months) PWID. We evaluated the contribution of incarceration to HCV transmission among PWID and the impact of prison-related prevention interventions, including scaling-up direct-acting antivirals (DAAs) in prison.

DESIGN

Dynamic mathematical modelling of incarceration and HCV transmission, using approximate Bayesian computation for model calibration.

SETTING

Scotland, UK.

PARTICIPANTS

A simulated population of PWID.

MEASUREMENTS

Population-attributable fraction (PAF) of incarceration to HCV transmission among PWID. Decrease in HCV incidence and chronic prevalence due to current levels of prison opiate substitution therapy (OST; 57% coverage) and HCV treatment, as well as scaling-up DAAs in prison and/or preventing the elevated risk associated with prison release.

FINDINGS

Incarceration contributes 27.7% [PAF; 95% credible interval (CrI) -3.1 to 51.1%] of HCV transmission among PWID in Scotland. During the next 15 years, current HCV treatment rates (10.4/6.8 per 1000 incarcerated/community PWID annually), with existing prison OST, could reduce incidence and chronic prevalence among all PWID by a relative 10.7% (95% CrI = 8.4-13.3%) and 9.7% (95% CrI = 7.7-12.1%), respectively. Conversely, without prison OST, HCV incidence and chronic prevalence would decrease by 3.1% (95% CrI = -28.5 to 18.0%) and 4.7% (95% CrI = -11.3 to 14.5%). Additionally, preventing the heightened risk among recently released PWID could reduce incidence and chronic prevalence by 45.0% (95% CrI = 19.7-57.5%) and 33.3% (95% CrI = 15.6-43.6%) or scaling-up prison HCV treatments to 80% of chronic PWID prison entrants with sufficient sentences (>16 weeks) could reduce incidence and prevalence by 45.6% (95% CrI = 38.0-51.3%) and 45.5% (95% CrI = 39.3-51.0%), respectively.

CONCLUSIONS

Incarceration and the elevated transmission risk following prison release can contribute significantly to hepatitis C virus transmission among people who inject drugs. Scaling-up hepatitis C virus treatment in prison can provide important prevention benefits.

Prevalence and predictors of HCV among a cohort of opioid treatment patients in Dar es Salaam, Tanzania

BACKGROUND

The government of Tanzania launched an opioid treatment program (OTP), using methadone, in Dar es Salaam in February of 2011. Hepatitis C virus (HCV) is a leading cause of morbidity and mortality globally, especially among people who inject drugs (PWID). We conducted a cross-sectional study among PWID engaged in OTP in Dar es Salaam to describe the prevalence and predictors of HCV antibody serostatus.

METHODS

Routine programmatic data on patients enrolled in Muhimbili National Hospital's OTP clinic from February 2011 to January 2013 were utilized. Multivariable Poisson regression was used to examine factors associated with HCV antibody serostatus.

RESULTS

A total of 630 PWID enrolled into the OTP clinic during the study period, seven percent of which were women. The overall seroprevalence of HCV antibody was 57% (95% Confidence interval: 53-61%). In adjusted analysis, methadone patients who used heroin for 5-10 years (adjusted prevalence ratio; aPR=1.41; 95% CI: 1.10-1.81) and >10years (aPR=1.48; 95% CI: 1.17-1.88) were more likely to be HCV antibody positive, compared to patients who used heroin for <5years. Patients who reported sharing needles or other equipment at their last injection (aPR=1.20; 95% CI: 1.01-1.41; p=0.022), being arrested (aPR=1.20; 95% CI: 1.04-1.40; p=0.012) and who were HIV-positive (aPR=1.84; 95% CI: 1.56-2.16; p<0.001) were also more likely to be HCV antibody positive than their counterparts.

CONCLUSION

Our observed HCV antibody prevalence among PWID engaged in OTP is higher than previously reported estimates in Dar es Salaam. Predictors of HCV antibody serostatus in this sample were similar to those found among PWID in many other settings. Integrating HCV care and treatment into OTP clinics should be considered, leveraging lessons learned from the integration of HIV services into OTP. Global efforts to develop HCV care and treatment programs in low and middle-income countries are critical, especially among PWID who have a high burden of HCV.

Hepatitis C virus core antigen: A potential alternative to HCV RNA testing among persons with substance use disorders

BACKGROUND

The hepatitis C virus (HCV) core antigen (HCVcAg) may be an alternative diagnostic method to HCV RNA especially in populations such as substance users, the homeless or in resource-limited settings.

AIMS

To evaluate performance of HCVcAg test in patients with opioid use disorder (OUD) on methadone in order to document its performance characteristics in the target population and to ensure that its specificity remains consistent across different populations.

METHODS

HCVcAg levels from 109 methadone-maintained patients were compared to HCV RNA levels.

RESULTS

Mean age was 53.8±7.8years, 59.6% were male, 68.8% African American, and 44% HCV-infected. HCVcAg was detectable in 47 of 48 HCV-infected, and undetectable in all HCV RNA negative patients. The HCVcAg assay had sensitivity of 97.9% and specificity of 100%. Correlation with HCV RNA levels was excellent (r=0.88, 95% CI 0.76; 0.95, p<0.01).

CONCLUSION

HCVcAg has excellent performance for the diagnosis of HCV infection in patients with OUD on methadone.

Spontaneous Clearance of Hepatitis C Virus Infection Among Human Immunodeficiency Virus-Infected Men Who Have Sex With Men

We assessed spontaneous clearance in 27 human immunodeficiency virus-infected men who have sex with men (MSM) who seroconverted for hepatitis C virus (HCV). In contrast with a recent estimate of 45.8%, we found a spontaneous clearance rate of 11.1% (95% confidence interval = 2.4-29.2). This finding suggests that treatment deferral to await spontaneous clearance might not be justified for MSM with sexually acquired HCV.

Impact of treatment on hepatitis C virus transmission and incidence in Egypt: A case for treatment as prevention

Egypt has launched a hepatitis C virus (HCV) treatment programme using direct-acting antivirals (DAAs). Our aim was to assess the impact of five plausible programme scale-up and sustainability scenarios for HCV treatment as prevention in Egypt. We developed and analysed a mathematical model to assess programme impact using epidemiologic, programming and health economics measures. The model was parametrized with current and representative natural history, HCV prevalence and programme data. HCV incidence in Egypt is declining, but will persist at a considerable level for decades unless controlled by interventions. Across the five programme scenarios, 1.75-5.60 million treatments were administered by 2030. Reduction in incidence (annual number of new infections) by 2030 ranged between 29% and 99%, programme-attributed reduction in incidence rate (new infections per susceptible person per year) ranged between 18% and 99%, number of infections averted ranged between 42 393 and 469 599, and chronic infection prevalence reached as low as 2.8%-0.1%. Reduction in incidence rate year by year hovered around 7%-15% in the first decade of the programme in most scenarios. Treatment coverage in 2030 ranged between 24.9% and 98.8%, and number of treatments required to avert one new infection ranged between 9.5 and 12.1. Stipulated targets for HCV by 2030 could not be achieved without scaling-up treatment to 365 000 per year and sustaining it for a decade. In conclusion, DAA scale-up will have an immense and immediate impact on HCV incidence in Egypt. Elimination by 2030 is feasible if sufficient resources are committed to programme scale-up and sustainability. HCV treatment as prevention is a potent and effective prevention approach.

Hepatitis B reactivation during or after direct acting antiviral therapy - implication for susceptible individuals

The FDA issued a warning following 24 cases of HBV reactivation during DAA therapy for HCV, including individuals with inactive, occult and past HBV infection. Clinical presentations ranged from asymptomatic fluctuations in HBV DNA to fulminant hepatic failure, liver transplantation and death. The mechanism is unknown. Areas covered: HCV/HBV coinfection is common, particularly in regions endemic for HBV. HCV and HBV utilize host factors to support replication; both viruses evade/impair host immunity. Clinical presentations of HBV reactivation during DAAs are summarized. Other causes of HBV reactivation are revisited and recent data regarding HBV reactivation are presented. Expert opinion: HBV reactivation during DAAs for HCV occurs, with life-threatening consequences in some individuals. The risk of HBV reactivation is observed in all HBV stages. The rapid removal of HCV likely alters and liberates host-viral ± viral-viral interactions that lead to increased HBV replication. As immune reconstitution occurs with HCV removal, host recognition of HBV DNA likely ensues followed by vigorous host immune responses leading to liver injury (HBV flare). These cases highlight the importance of HBV testing prior to initiating DAA therapy, the need for close monitoring of HBV during therapy and timely administration of anti-HBV therapy to prevent serious sequelae.

Spontaneous clearance of chronic hepatitis C is rare in HIV-infected patients after effective use of combination antiretroviral therapy

Objective

To evaluate the rate of spontaneous resolution of chronic hepatitis C (CHC) infection in a cohort of HIV-infected patients.

Methods

A retrospective analysis of 509 HIV-infected patients with chronic HCV infection was performed at two reference hospitals in Andalusia. The main variable of the study was spontaneous clearance of CHC, defined as a negative HCV RNA result after at least two previous quantitative measurements of HCV RNA separated by a minimum of 12 months.

Results

Of 509 patients, 3 (0.59%; 95% CI: 0.15%-1.6%) experienced spontaneous clearance of CHC. After combination antiretroviral therapy (cART) initiation, two of three cases experienced an increased CD4⁺ count, coinciding with HCV viral clearance. All patients were IL28B CC carriers, 2 were co-infected with HCV genotype 3 (the HCV genotype of the remaining patient was not available).

Conclusions

Spontaneous clearance of CHC is a rare event in the context of HIV/HCV co-infected patients and may be associated with the effective use of cART and thus HIV suppression.

Role of primary T-cell immunodeficiency and hepatitis B coinfection on spontaneous clearance of hepatitis C: The BC Hepatitis Testers Cohort

T-cell host immune response against hepatitis C virus (HCV) has been suggested to play an important role in determining HCV infection outcome. However, data from human studies are not available. This study examined the effect of primary T-cell deficiency along with other factors on the spontaneous clearance of HCV in a large population-based cohort in British Columbia, Canada. The BC Hepatitis Testers Cohort includes all individuals tested for HCV in BC in 1990-2013 linked with data on their medical visits, hospitalizations and prescription drugs. HCV-positive individuals with at least one valid HCV PCR test on/after HCV diagnosis (n=46 783) were included in this study. To examine factors associated with the spontaneous clearance of HCV, multivariable logistic regression was fitted on the full sample, and Cox proportional hazards model on the HCV seroconverters. Spontaneous clearance was observed in 25.1% (n=11 737) of those tested for HCV. After adjusting for potential confounders, the odds of spontaneous clearance of HCV was lower in people with primary T-cell immunodeficiency (adjusted odds ratio [aOR]: 0.55, 95% CI: 0.32-0.94), and higher in females (aOR: 1.61, 95% CI: 1.54-1.68) and in those coinfected with HBV (aOR: 2.31, 95% CI: 1.93-2.77). Similar results were observed in HCV seroconverters except HBV coinfection was not significant. In conclusion, primary T-cell immunodeficiency is associated with a lower spontaneous clearance of HCV while female sex and coinfection with HBV are associated with a higher spontaneous clearance.

Viral and host factors associated with outcomes of hepatitis C virus infection (Review)

Hepatitis C virus (HCV) infection is a major health issue globally. Owing to the progress made in host genetics and HCV molecular virology, emerging data have suggested that the natural course and treatment response in patients with HCV infection are largely determined by complex host‑viral interactions. HCV genotype is the most important viral factor predicting the response to pegylated interferon‑α plus ribavirin therapy. The subtype of HCV genotype 1 is the key viral factor that predicts the efficacy of direct‑acting antiviral therapy. HCV genome heterogeneity and baseline viral load are additionally associated with the treatment response. Multiple host genetic variants localized in genes associated with the immune response have been identified as predictors of spontaneous disease course and therapy outcome in chronic HCV. However, most findings from candidate gene association studies have not been proven universal for all investigated populations and independent studies. Previous findings in independent large genome wide association studies confirmed that interferon‑λ3 gene polymorphisms are associated with spontaneous clearance and treatment responsiveness. A polymorphism of the inosine triphosphatase gene has been identified as a protective factor against ribavirin‑induced anemia and dose reductions. Another genetic variant in the patatin‑like phospholipase domain containing 3 genes is associated with hepatic steatosis and fibrosis in patients with HCV. The present review focused on the identified viral and host factors associated with outcomes of patients with HCV, and assessed the involvement of viral and host genetics in the natural history and treatment outcomes of HCV infection. This will provide novel ideas concerning personalized prevention and individualized clinical management.

17,β-estradiol inhibits hepatitis C virus mainly by interference with the release phase of its life cycle

BACKGROUND & AIMS

Oestrogen and oestrogen-mediated signalling protect from hepatitis C virus through incompletely understood mechanisms. We aimed to ascertain which phase(s) of hepatitis C virus life cycle is/are affected by oestrogens.

METHODS

Huh7 cells infected with the JFH1 virus (genotype 2a) were exposed to dehydroepiandrosterone, testosterone, progesterone and 17β-estradiol (tested with/without its receptor antagonist fulvestrant). Dose-response curves were established to calculate half maximal inhibitory concentration values. To dissect how 17β-estradiol interferes with phases of hepatitis C virus life cycle, its effects were measured on the hepatitis C virus pseudo-particle system (viral entry), the subgenomic replicon N17/JFH1 and the replicon cell line Huh7-J17 (viral replication). Finally, in a dual-step infection model, infectious supernatants, collected from infected cells exposed to hormones, were used to infect naïve cells.

RESULTS

Progesterone and testosterone showed no inhibitory effect on hepatitis C virus; dehydroepiandrosterone was only mildly inhibitory. In contrast, 17β-estradiol inhibited infection by 64%-67% (IC₅₀ values 140-160 nmol/L). Fulvestrant reverted the inhibition by 17β-estradiol in a dose-dependent manner. 17β-estradiol exerted only a slight inhibition (<20%) on hepatitis C virus pseudo-particles, and had no effect on cells either transiently or stably (Huh7-J17 cells) expressing the N17/JFH1 replicon. In the dual-step infection model, a significant half maximal inhibitory concentration decline occurred between primary (134 nmol/L) and secondary (100 nmol/L) infections (P=.02), with extracellular hepatitis C virus RNA and infectivity being reduced to a higher degree in comparison to its intracellular counterpart.

CONCLUSIONS

17β-estradiol inhibits hepatitis C virus acting through its intracellular receptors, mainly interfering with late phases (assembly/release) of the hepatitis C virus life cycle.

Estimating cost-effectiveness associated with all-oral regimen for chronic hepatitis C in China

Background

All-oral regimens are associated with higher effectiveness and shorter treatment duration for chronic hepatitis C. Given its superior effect and enormous patients in China, clinicians or patients may be compelled to consider delaying treatment for all-oral regimen.

Objective

To estimate cost-effectiveness of delaying treatment for all-oral regimen in the subsequent years under different assumptions about their price and efficacy compared with standard of care in China.

Methods

A state-transition Markov model was developed to estimate lifetime costs and quality-adjusted life years (QALYs). Incremental cost-effectiveness ratio (ICER) and net monetary benefit (NB) were calculated. And sensitivity analyses were also performed to assess the impact of uncertainty.

Results

For treatment naive patients with Genotype 1, immediate treatment with all-oral regimen under assumed cost and efficacy at present was cost-effective compared with peginterferon α-2a (PegIFN) regimen at present with an ICER of $12536 per QALY gained and a positive NB of $6832 at a willingness-to-pay threshold of $21209. And it was more than 95% likely to be cost-effective if weekly drug cost was less than $1000. Moreover, patients delaying treatment for all-oral regimen in the 1^st year were associated with increase in QALYs of 0.62 and increase in cost of $10114 compared with initiating PegIFN regimen at present, which resulted in a positive NB of $3115.

Conclusion

From a payer perspective, all-oral regimen is associated with good long-term health and economic benefit for treatment-naive patients infected with HCV genotype 1. Particularly, if all-oral regimen would become available at lower price in the future, delaying treatment for all-oral regimen may be a good choice for patients in China.

HBV/HCV co-infection is associated with a high level of HCV spontaneous clearance among drug users and blood donors in China

Understanding the biology of spontaneous clearance of hepatitis C virus (HCV) infection could lead to improved strategies to prevent the sequelae associated with chronic HCV infection. Chronic infections with hepatitis virus are very common in China, but the factors associated with spontaneous clearance of HCV have not been adequately studied. We evaluated the spontaneous clearance of HCV among 1918 drug users and 1526 HCV-seropositive blood donors in Guangzhou, China. Among participants who were co-infected with hepatitis B virus (HBV), 41.38% of drug users and 39.47% of blood donors had cleared their HCV infection without antiviral therapy compared to 9.41% of drug users and 16.73% of blood donors who were mono-infected with a single virus (P<.01). The proportion of subjects who had cleared their HCV infection was significantly greater in the co-infected subjects whose serum HBV DNA was greater than 2000IU/mL than those with lower levels. A multiple logistic regression analysis found female gender, IL28B rs8099917 TT genotype, HBV co-infection and blood donors (vs drug users) associated with increased spontaneous clearance of HCV infection. Although acute HCV infections are common in China, the incidence of chronic HCV may be reduced among the high prevalence of chronic HBV and IL28B genotypes associated with spontaneous clearance of HCV in Chinese populations.

Gender differences in liver disease and the drug-dose gender gap

Although gender-based medicine is a relatively recent concept, it is now emerging as an important field of research, supported by the finding that many diseases manifest differently in men and women and therefore, might require a different treatment. Sex-related differences regarding the epidemiology, progression and treatment strategies of certain liver diseases have long been known, but most of the epidemiological and clinical trials still report results only about one sex, with consequent different rate of response and adverse reactions to treatment between men and women in clinical practice. This review reports the data found in the literature concerning the gender-related differences for the most representative hepatic diseases.

Treatment of hepatitis C virus infection: updated Swedish Guidelines 2016

In a recent expert meeting, Swedish recommendations for the treatment of hepatitis C virus (HCV) infection were updated. An interferon-free combination of direct-acting antiviral agents is considered and indicated for all patients with chronic HCV infection, but the ability to treat all is limited primarily by high cost of medication. The group of patients prioritized for therapeutic intervention has been extended to also include fertile women desiring to become pregnant. A more thorough discussion of treatment for people who inject drugs (PWIDs) in order to diminish transmission is included, and the clinical significance of baseline NS5A resistance associated variants (RAVs), also known as resistance associated substitutions (RASs), for the treatment of HCV genotype 1a or 3 infection is discussed.

Chronic hepatitis C infection and liver disease in HIV-coinfected patients in Asia

Data on markers of hepatitis C virus (HCV) disease in HIV-HCV-coinfected patients in resource-limited settings are scarce. We assessed HCV RNA, HCV genotype (GT), IL28B GT and liver fibrosis (FibroScan® ) in 480 HIV-infected patients with positive HCV antibody in four HIV treatment centres in South-East Asia. We enrolled 165 (34.4%) patients in Jakarta, 158 (32.9%) in Bangkok, 110 (22.9%) in Hanoi and 47 (9.8%) in Kuala Lumpur. Overall, 426 (88.8%) were male, the median (IQR) age was 38.1 (34.7-42.5) years, 365 (76.0%) reported HCV exposure through injecting drug use, and 453 (94.4%) were on combination antiretroviral therapy. The median (IQR) CD4 count was 446 (325-614) cells/mm3 and 208 (94.1%) of 221 patients tested had HIV-1 RNA <400 copies/mL. A total of 412 (85.8%) had detectable HCV RNA, at a median (IQR) of 6.2 (5.4-6.6) log10 IU/mL. Among 380 patients with HCV GT, 223 (58.7%) had GT1, 97 (25.5%) had GT3, 43 (11.3%) had GT6, eight (2.1%) had GT4, two (0.5%) had GT2, and seven (1.8%) had indeterminate GT. Of 222 patients with IL28B testing, 189 (85.1%) had rs12979860 CC genotype, and 199 (89.6%) had rs8099917 TT genotype. Of 380 patients with FibroScan® , 143 (37.6%) had no/mild liver fibrosis (F0-F1), 83 (21.8%) had moderate fibrosis (F2), 74 (19.5%) had severe fibrosis (F3), and 79 (20.8%) had cirrhosis (F4). One patient (0.3%) had FibroScan® failure. In conclusion, a high proportion of HIV-HCV-coinfected patients had chronic HCV infection. HCV GT1 was predominant, and 62% of patients had liver disease warranting prompt treatment (≥F2).

Profile of Roche's cobas® HCV tests

INTRODUCTION

Molecular assays for detection and accurate quantitation of hepatitis C virus (HCV) RNA have been important for identification and management of the hepatitis C. Furthermore, the HCV genotype should be assessed prior to treatment initiation. Recently, Roche developed the cobas® HCV tests for use on the cobas® 6800/8800 Systems and the cobas® 4800 System and the cobas® HCV genotyping (GT) test for use on the cobas® 4800 System. Areas covered: The analytic and clinical performance of the newly-developed tests is described according to the currently existing literature. Both tests for detection and quantitation of HCV RNA have been shown to be sensitive and linear, and correlate well with established Roche tests used in the routine diagnostic laboratory. The cobas® HCV GT test shows a good performance and is suitable for identification of HCV genotypes 1 to 6 and genotype 1 subtypes a and b in clinical specimens from individuals with chronic HCV infection. Expert commentary: The new tests are effective in screening for hepatitis C infection and in the management of patients with chronic HCV infection ensuring full HCV genotype coverage. They will replace the established Roche tests within the next few years.

Prevalence of Hepatitis C Virus Infection and Its Risk Factors among Patients Attending Rwanda Military Hospital, Rwanda

In Rwanda, the prevalence of viral hepatitis (HCV) is poorly understood. The current study investigated the prevalence and risk factors of HCV infection in Rwanda. A total of 324 patients attending Rwanda Military Hospital were randomly selected and a questionnaire was administered to determine the risk factors. Blood was collected and screened for anti-HCV antibodies and seropositive samples were subjected to polymerase chain reaction method. Hematology abnormalities in the HCV infected patients were also investigated. Anti-HCV antibody and active HCV infection were found in 16.0% and 9.6% of total participants, respectively. Prevalence was highest (28.4%; 19/67) among participants above 55 years and least (2.4%; 3/123) among younger participants (18-35 years). There was a significant (P = 0.031) relationship between place of residence and HCV infection with residents of Southern Province having significantly higher prevalence. The hematological abnormalities observed in the HCV infected patients included leukopenia (48.4%; 15/52), neutropenia (6.5%; 2/52), and thrombocytopenia (25.8%; 8/52). The HCV infection was significantly higher in the older population (>55 years) and exposure to injection from traditional practitioners was identified as a significant (P = 0.036) risk factor of infection. Further studies to determine the factors causing the high prevalence of HCV in Rwanda are recommended.

Hepatitis C Virus Postexposure Prophylaxis in the Healthcare Worker: Why Direct-Acting Antivirals Don't Change a Thing

Currently, 380 000-400 000 occupational exposures to blood-borne pathogens occur annually in the United States. The management for occupational HIV or hepatitis B virus exposures includes postexposure prophylaxis (PEP) when necessary; however, PEP is not recommended for hepatitis C virus (HCV) exposures. Recent approval of HCV direct-acting antivirals (DAAs) has renewed discussions as to whether these therapies could be used to prevent infection after exposure. There are no published studies addressing this question, but the prescribing of DAAs for PEP has been reported. We will discuss the differences in transmission of the 3 most common blood-borne pathogens, the natural history of early HCV infection, and the scientific rationale for PEP. In particular, we will discuss how the low feasibility of conducting an adequately powered clinical trial of DAA use for PEP and the low cost-effectiveness of such an intervention is not supportive of targeting limited resources for such use.

Spontaneous Elimination of Hepatitis C Virus Infection

Hepatitis C virus (HCV) is the etiological agent of chronic hepatitis C and a major cause of liver cirrhosis and hepatocellular carcinoma. Only a minority of infected individuals can clear the virus spontaneously. The knowledge of the determinants of virus clearance would allow the development of effective methods preventing its further spread and optimizing treatment regimens. Viral factors associated with spontaneous virus clearance in the acute phase of infection, such as HCV genotype, virus heterogeneity, and the impact of viral proteins on the immune system have been characterized. Likewise, host genetic markers, such as the interleukin genotypes, HLA alleles, and factors affecting the T lymphocyte response appear to play an important role. Studies have revealed that natural clearance of HCV infection in the chronic phase is rare and its mechanisms are not well understood. In this review, we present the state-of-the art knowledge on the viral and host factors affecting the spontaneous elimination of HCV infection.

Chronic hepatitis C burden and care cascade in Australia in the era of interferon-based treatment

BACKGROUND AND AIM

Interferon-free direct-acting antiviral regimens for hepatitis C virus (HCV) infection have been recently available in Australia, beginning a new era in clinical and public health management of HCV infection. This study provided updated estimates of the HCV infection care cascade and burden in Australia as a reliable platform for assessing the future impact of interferon-free therapies.

METHODS

A modeling approach was applied to estimate the number of individuals living with chronic HCV infection and with various liver disease stages. Data from national registries of HCV notification and liver transplantation, literature review, and expert consensus informed the model parameters. HCV notification and Pharmaceutical Benefits Scheme data were used to estimate the number of HCV diagnosed individuals and treatment uptake.

RESULTS

In 2014, an estimated 230 470 individuals (range: 180 490-243 990) were living with HCV, among whom 75% were diagnosed (n = 172 720; range: 156 720-188 770), 20% had ever received treatment (n = 45 000; range: 39 280-50 720), and 11% had been cured (n = 24 750; range: 21 520-27 990). Among individuals with HCV infection, the proportion with hepatic fibrosis stage ≥F3 doubled during the last decade, increasing from 9% (n = 18 580) in 2004 to 19% (n = 44,730) in 2014. Individuals initiating HCV treatment increased from 1100 in 1997 to 3840 in 2007, plateaued until 2010 and decreased to 2790 in 2014.

CONCLUSIONS

The burden of HCV-related liver disease has increased markedly. Although the proportion diagnosed was high, treatment uptake remained low, with no increase over the last 7 years. Reducing the HCV burden in Australia requires scale-up of interferon-free HCV therapies.

The effects of alcohol on spontaneous clearance of acute hepatitis C virus infection in females versus males

BACKGROUND

Approximately one quarter of persons exposed to hepatitis C virus (HCV) will spontaneously clear infection. We undertook this study to investigate the impact of alcohol on likelihood of HCV spontaneous viral clearance stratified by sex groups.

METHODS

Pooled data from an international collaboration of prospective observational studies of incident HIV and HCV infection in high-risk cohorts (the InC3 Study) was restricted to 411 persons (or 560.7 person-years of observation) with documented acute HCV infection and data regarding alcohol use. The predictor of interest was self-reported alcohol use at or after estimated date of incident HCV infection and the outcome was HCV spontaneous clearance. Sex stratified Cox proportional hazards models were used to evaluate the association between alcohol and spontaneous clearance, adjusting for age, race/ethnicity, and IFNL4 genotype.

RESULTS

The median age was 28.5 years, 30.4% were women, 87.2% were white, and 71.8% reported alcohol use at or after incident infection. There were 89 (21.6%) cases of spontaneous clearance observed, 39 (31.2%) among women and 50 (17.5%) in men (p<0.01). Overall, spontaneous clearance occurred less frequently among participants who drank alcohol compared to those who did not drink (18.9% v. 28.5%, p=0.03). After adjustment for other covariates, alcohol was significantly and independently associated with lower relative hazards for spontaneous clearance of HCV in women (AHR=0.35; 95% CI: 0.19-0.66; p=0.001) but not in men (AHR=0.63; 95% CI: 0.36-1.09; p=0.10).

CONCLUSION

Results indicate that abstaining from drinking alcohol may increase the likelihood of spontaneous clearance among women.

Maximum levels of hepatitis C virus lipoviral particles are associated with early and persistent infection

BACKGROUND & AIMS

Hepatitis C virus (HCV) is bound to plasma lipoproteins and circulates as an infectious lipoviral particle (LVP). Experimental evidence indicates that LVPs have decreased susceptibility to antibody-mediated neutralisation and higher infectivity. This study tested the hypothesis that LVPs are required to establish persistent infection, and conversely, low levels of LVP in recent HCV infection increase the probability of spontaneous HCV clearance.

METHODS

LVP in non-fasting plasma was measured using the concentration of HCV RNA bound to large >100 nm sized lipoproteins after ex vivo addition of a lipid emulsion, that represented the maximum concentration of LVP (maxi-LVP). This method correlated with LVP in fasting plasma measured using iodixanol density gradient ultracentrifugation. Maxi-LVP was measured in a cohort of 180 HCV participants with recent HCV infection and detectable HCV RNA from the Australian Trial in Acute Hepatitis C (ATAHC) and Hepatitis C Incidence and Transmission Study in prison (HITS-p) cohorts.

RESULTS

Spontaneous clearance occurred in 15% (27 of 180) of individuals. In adjusted analyses, low plasma maxi-LVP level was independently associated with spontaneous HCV clearance (≤827 IU/ml; adjusted odds ratio 3.98, 95% CI: 1.02, 15.51, P = 0.047), after adjusting for interferon lambda-3 rs8099917 genotype, estimated duration of HCV infection and total HCV RNA level.

CONCLUSIONS

Maxi-LVP is a biomarker for the maximum concentration of LVP in non-fasting samples. Low maxi-LVP level is an independent predictor of spontaneous clearance of acute HCV.

Sofosbuvir and ribavirin in acute hepatitis C-infected patient with decompensated cirrhosis

BACKGROUND

The treatment of chronic hepatitis C virus infection has been revolutionized by the advent of direct-acting antiviral agents. However, evidence of its effects on patients with acute hepatitis C (AHC) virus infection is limited.

CASE SUMMARY

We report the case of a patient with decompensated cirrhosis induced by autoimmune liver disease, whose condition rapidly deteriorated following AHC virus infection. The patient received sofosbuvir and ribavirin combination treatment for 12 weeks. Serum hepatitis C virus RNA remained undetectable 36 weeks after discontinuing sofosbuvir and ribavirin.

CONCLUSION

Our findings support the use of sofosbuvir and ribavirin as a treatment in AHC patients with decompensated cirrhosis.

Identification of the transcripts associated with spontaneous HCV clearance in individuals co-infected with HIV and HCV

BACKGROUND

Infection with human immunodeficiency virus (HIV) influences the outcome and natural disease progression of hepatitis C virus (HCV) infection. While the majority of HCV mono-infected and HCV/HIV co-infected subjects develop chronic HCV infection, 20-46% of mono- and co-infected subjects spontaneously clear HCV infection. The mechanism underlying viral clearance is not clearly understood. Analysis of differential cellular gene expression (mRNA) between HIV-infected patients with persistent HCV infection or spontaneous clearance could provide a unique opportunity to decipher the mechanism of HCV clearance.

METHODS

Plasma RNA from HIV/HCV co-infected subjects who cleared HCV and those who remained chronically infected with HCV was sequenced using Ion Torrent technology. The sequencing results were analyzed to identify transcripts that are associated with HCV clearance by measuring differential gene expression in HIV/HCV co-infected subjects who cleared HCV and those who remained chronically infected with HCV.

RESULTS

We have identified plasma mRNA, the levels of which are significantly elevated (at least 5 fold, False Discovery Rate (FDR) <0.05) before HCV infection in subjects who cleared HCV compared to those who remained chronically infected. Upon further analysis of these differentially expressed genes, before and after HCV infection, we found that before HCV infection 12 genes were uniquely upregulated in the clearance group compared to the chronically infected group. Importantly, a number of these 12 genes and their upstream regulators (such as CCL3, IL17D, LBP, SOCS3, NFKBIL1, IRF) are associated with innate immune response functions.

CONCLUSIONS

These results suggest that subjects who spontaneously clear HCV may express these unique genes associated with innate immune functions.

Incorporating HIV/hepatitis B virus/hepatitis C virus combined testing into routine blood tests in nine UK Emergency Departments: the "Going Viral" campaign

OBJECTIVES

Routine HIV screening is recommended in those UK hospitals and primary care settings where the HIV prevalence is > 0.2%. For hepatitis B virus (HBV) and hepatitis C virus (HCV), however, testing is targeted at at-risk groups. We investigated the prevalence of these blood-borne viruses (BBVs) during a routine testing pilot in UK Emergency Departments (EDs).

METHODS

During the "Going Viral" campaign (13-19 October 2014), nine UK EDs in areas of high HIV prevalence offered routine tests for HIV, HBV and HCV to adults having blood taken as part of routine care. Patients who tested positive were linked to care.

RESULTS

A total of 7807 patients had blood taken during their ED visit; of these, 2118 (27%) were tested for BBVs (range 9-65%). Seventy-one BBV tests were positive (3.4%) with 32 (45.1%) new diagnoses. There were 39 HCV infections (15 newly diagnosed), 17 HIV infections (six newly diagnosed), and 15 HBV infections (11 newly diagnosed). Those aged 25-54 years had the highest prevalence: 2.46% for HCV, 1.36% for HIV and 1.09% for HBV. Assuming the cost per diagnosis is £7, the cost per new case detected would be £988 for HCV, £1351 for HBV and £2478 for HIV.

CONCLUSIONS

In the first study in the UK to report prospectively on BBV prevalence in the ED, we identified a high number of new viral hepatitis diagnoses, especially hepatitis C, in addition to the HIV diagnoses. Testing for HIV alone would have missed 54 viral hepatitis diagnoses (26 new), supporting further evaluation of routine BBV testing in UK EDs.

Time to decompensated cirrhosis and hepatocellular carcinoma after an HBV or HCV notification: A population-based study

BACKGROUND & AIMS

Delayed hepatitis B virus (HBV) or hepatitis C virus (HCV) diagnosis may increase risk of advanced liver disease complications, including decompensated cirrhosis (DC) and hepatocellular carcinoma (HCC). The aim of this study was to characterise "late hepatitis notification" among people with an HBV/HCV notification and advanced liver disease in New South Wales, Australia.

METHODS

HBV/HCV notifications 1995-2012 were linked to cancer registry and hospital admissions. Late hepatitis notification was defined by a notification after, at the time, or within two years before DC/HCC diagnosis.

RESULTS

HBV and HCV cohorts comprised 50,958 and 79,727 individuals, respectively. Among people with DC (n=3869), late HBV notification declined from 64% (88/138) during 2001-2002 to 31% (46/149) in 2011-2012 (p<0.001), and late HCV notification declined from 52% (179/341) during 2001-2002 to 22% (134/605) in 2011-2012 (p<0.001). Among people with HCC (n=1656), late HBV notification declined from 68% (59/87) during 2001-2002 to 29% (37/128) in 2011-2012 (p<0.001), and late HCV notification declined from 51% (40/79) during 2001-2002 to 17% (49/288) in 2011-2012 (p<0.001).

CONCLUSIONS

Despite significant declines in late hepatitis notification since early 2000s, efforts to enhance hepatitis screening, particularly for HBV, are required. Late hepatitis notification as described in this study could be used as a measure of population-level HBV/HCV screening.

LAY SUMMARY

Delayed hepatitis B virus (HBV) or hepatitis C virus (HCV) diagnosis may increase the risk of advanced liver disease complications, including decompensated cirrhosis (DC) and hepatocellular carcinoma (HCC). The aim of this study was to characterise "late hepatitis notification" among people with an HBV or HCV notification in New South Wales, Australia. Late hepatitis notifications have significantly declined since early 2000s; however, efforts to enhance hepatitis screening, particularly for HBV, are required. Late hepatitis notification as described in this study could be used as a measure of population-level HBV/HCV screening.

Hepatitis C virus Broadly Neutralizing Monoclonal Antibodies Isolated 25 Years after Spontaneous Clearance

Hepatitis C virus (HCV) is world-wide a major cause of liver related morbidity and mortality. No vaccine is available to prevent HCV infection. To design an effective vaccine, understanding immunity against HCV is necessary. The memory B cell repertoire was characterized from an intravenous drug user who spontaneously cleared HCV infection 25 years ago. CD27+IgG+ memory B cells were immortalized using BCL6 and Bcl-xL. These immortalized B cells were used to study antibody-mediated immunity against the HCV E1E2 glycoproteins. Five E1E2 broadly reactive antibodies were isolated: 3 antibodies showed potent neutralization of genotype 1 to 4 using HCV pseudotyped particles, whereas the other 2 antibodies neutralized genotype 1, 2 and 3 or 1 and 2 only. All antibodies recognized non-linear epitopes on E2. Finally, except for antibody AT12-011, which recognized an epitope consisting of antigenic domain C /AR2 and AR5, all other four antibodies recognized epitope II and domain B. These data show that a subject, who spontaneously cleared HCV infection 25 years ago, still has circulating memory B cells that are able to secrete broadly neutralizing antibodies. Presence of such memory B cells strengthens the argument for undertaking the development of an HCV vaccine.

Cost-Effectiveness of Hepatitis C Treatment for People Who Inject Drugs and the Impact of the Type of Epidemic; Extrapolating from Amsterdam, the Netherlands

BACKGROUND

People who inject drugs (PWID) are disproportionally affected by the hepatitis C virus (HCV) infection. The efficacy of HCV treatment has significantly improved in recent years with the introduction of direct-acting antivirals (DAAs). However, DAAs are more costly than pegylated-interferon and ribavirin (PegIFN/RBV). We aimed to assess the cost-effectiveness of four HCV treatment strategies among PWID and treatment scale-up.

METHODS

An individual-based model was used describing HIV and HCV transmission and disease progression among PWID. We considered two epidemiological situations. A declining epidemic, based on the situation in Amsterdam, the Netherlands, and a stable HCV epidemic, as observed in other settings. Data on HCV incidence, prevalence, treatment setting and uptake were derived from observed data among PWID in Amsterdam. We assessed the incremental cost-effectiveness ratio (ICER, costs in €/quality-adjusted life year (QALY)) of four treatment strategies: 1) PegIFN/RBV; 2) sofosbuvir/RBV for genotype 2-3 and dual DAA for genotype 1-4; 3) Dual DAA for all genotypes; 4) Dual DAA with 3x treatment uptake.

RESULTS

In both types of epidemic, dual DAA therapy was most cost-effective strategy. In the declining epidemic, dual DAA yielded an ICER of 344 €/QALY while in the stable epidemic dual DAA led to cost-savings. Scaling-up treatment was also highly cost-effective. Our results were robust over a range of sensitivity analyses.

CONCLUSION

HCV treatment with DAA-containing regimens is a highly cost-effective intervention among PWID. Based on the economic and population benefits of scaling-up treatment, stronger efforts are needed to achieve higher uptake rates among PWID.

Acute Liver Damage Associated with Innate Immune Activation in a Small Nonhuman Primate Model of Hepacivirus Infection

Despite its importance in shaping adaptive immune responses, viral clearance, and immune-based inflammation, tissue-specific innate immunity remains poorly characterized for hepatitis C virus (HCV) infection due to the lack of access to acutely infected tissues. In this study, we evaluated the impact of natural killer (NK) cells and myeloid (mDCs) and plasmacytoid (pDCs) dendritic cells on control of virus replication and virus-induced pathology caused by another, more rapidly resolving hepacivirus, GB virus B (GBV-B), in infections of common marmosets. High plasma and liver viral loads and robust hepatitis characterized acute GBV-B infection, and while viremia was generally cleared by 2 to 3 months postinfection, hepatitis and liver fibrosis persisted after clearance. Coinciding with peak viral loads and liver pathology, the levels of NK cells, mDCs, and pDCs in the liver increased up to 3-fold. Although no obvious numerical changes in peripheral innate cells occurred, circulating NK cells exhibited increased perforin and Ki67 expression levels and increased surface expression of CXCR3. These data suggested that increased NK cell arming and proliferation as well as tissue trafficking may be associated with influx into the liver during acute infection. Indeed, NK cell frequencies in the liver positively correlated with plasma (R = 0.698; P = 0.015) and liver (R = 0.567; P = 0.057) viral loads. Finally, soluble factors associated with NK cells and DCs, including gamma interferon (IFN-γ) and RANTES, were increased in acute infection and also were associated with viral loads and hepatitis. Collectively, the findings showed that mobilization of local and circulating innate immune responses was linked to acute virus-induced hepatitis, and potentially to resolution of GBV-B infection, and our results may provide insight into similar mechanisms in HCV infection.

IMPORTANCE

Hepatitis C virus (HCV) infection has created a global health crisis, and despite new effective antivirals, it is still a leading cause of liver disease and death worldwide. Recent evidence suggests that innate immunity may be a potential therapeutic target for HCV, but it may also be a correlate of increased disease. Due to a lack of access to human tissues with acute HCV infection, in this study we evaluated the role of innate immunity in resolving infection with a hepacivirus, GBV-B, in common marmosets. Collectively, our data suggest that NK cell and DC mobilization in acute hepacivirus infection can dampen virus replication but also regulate acute and chronic liver damage. How these two opposing effects on the host may be modulated in future therapeutic and vaccine approaches warrants further study.

Tackling the burden of the hepatitis C virus in the UK: characterizing and assessing the clinical and economic consequences

OBJECTIVES

The hepatitis C virus (HCV) remains a significant public health issue. This study aimed to quantify the clinical and economic burden of chronic hepatitis C in the UK, stratified by disease severity, age and awareness of infection, with concurrent assessment of the impact of implementing a treatment prioritization approach.

STUDY DESIGN AND METHODS

A previously published back projection, natural history and cost-effectiveness HCV model was adapted to a UK setting to estimate the disease burden of chronic hepatitis C and end-stage liver disease (ESLD) between 1980 and 2035. A published meta-regression analysis informed disease progression, and UK-specific data informed other model inputs.

RESULTS

At 2015, prevalence of chronic hepatitis C is estimated to be 241,487 with 22.20%, 33.72%, 17.22%, 16.67% and 10.19% of patients in METAVIR stages F0, F1, F2, F3 and F4, respectively, but is estimated to fall to 193,999 by 2035. ESLD incidence is predicted to peak in 2031. Assuming all patients are diagnosed and treatment is prioritized in F3 and F4 using highly efficacious direct-acting antiviral (DAA) regimens, a 69.85% reduction in ESLD incidence is predicted between 2015 and 2035, and the cumulative discounted medical expenditure associated with the lifetime management of incident ESLD events is estimated to be £1,202,827,444.

CONCLUSIONS

The prevalence of chronic hepatitis C is expected to fall in coming decades; however, the ongoing financial burden is expected to be high due to an increase in ESLD incidence. This study highlights the significant costs of managing ESLD that are likely to be incurred without the employment of effective treatment approaches.

Spontaneous viral clearance of hepatitis C virus (HCV) infection among people who inject drugs (PWID) and HIV-positive men who have sex with men (HIV+ MSM): a systematic review and meta-analysis

Background

Hepatitis C virus (HCV) infection causes significant morbidity and mortality among people who inject drugs (PWID) and HIV+ men who have sex with men (MSM). Characterizing spontaneous viral clearance of HCV infection among PWID and HIV+ MSM is important for assessing the burden of disease and treatment strategies in these populations.

Methods

Electronic and other searches of medical literature were conducted. Reports were eligible if they presented original data from upper-middle- and high-income countries on laboratory-confirmed HCV infection and spontaneous viral clearance among PWID or HIV+ MSM. Pooled estimates of spontaneous viral clearance were generated using fixed-effect and random-effects models. Meta-regression examined potential predictors related to individual characteristics and research methodology.

Results

The meta-analysis estimated that spontaneous viral clearance occurs in 24.4 % of PWID and 15.4 % of HIV+ MSM. In univariate meta-regression among PWID, male sex and age were significantly associated with spontaneous viral clearance, and in multivariate analysis, male sex and HIV positivity were predictors of spontaneous viral clearance; among HIV+ MSM no variables were found to affect spontaneous viral clearance.

Conclusion

The variability in estimates of spontaneous viral clearance between HIV+ MSM and PWID suggests the impact of HIV co-infection and HCV re-infection. Due to limited data on additional factors that may affect the natural history of HCV, more research is needed to further understand spontaneous viral clearance in these risk groups.

Protocol registration

The protocols for the PWID and HIV+ MSM research were registered with PROSPERO (CRD42014008805; CRD42013006462).

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-016-1807-5) contains supplementary material, which is available to authorized users.

Application of network construction to estimate functional changes to insulin receptor substrates 1 and 2 in Huh7 cells following infection with the hepatitis C virus

Hepatitis C virus (HCV) is closely associated with insulin resistance (IS), acting primarily by interfering with insulin signaling pathways, increasing cytokine-mediated (tumor necrosis factor α, interleukin 6) inflammatory responses and enhancing oxidative stress. In the insulin signaling pathways, the insulin receptor substrate (IRS) is one of the key regulatory factors. The present study constructed gene regulatory sub‑networks specific for IRS1 and IRS2 in Huh7 cells and HCV‑infected Huh7 (HCV‑Huh7) cells using linear programming and a decomposition algorithm, and investigated the possible mechanisms underlying the function of IRS1/2 in HCV‑induced IS in Huh7 cells. All data were obtained from GSE20948 of the Gene Expression Omnibus database from the National Center for Biotechnology Information. Genes which were significantly differentially expressed between Huh7 and HCV‑Huh7 cells were analyzed using the significance analysis of microarray algorithm. The top 50 genes, including IRS1/2, were used as target genes to determine the gene regulatory networks and next the sub‑networks of IRS1 and IRS2 in HCV‑Huh7 and Huh7 cells using Gene Regulatory Network Inference Tool, an algorithm based on linear programming and the decomposition process. The IRS1/2 sub‑networks were divided into upstream/downstream groups and activation/suppression clusters, and were further analyzed using Molecule Annotation System 3.0 and Database for Annotation, Visualization, and Integrated Discovery software, two online platforms for enrichment and clustering analysis and visualization. The results indicated that in Huh7 cells, the downstream network of IRS2 is more complex than that of IRS1, indicating that the insulin metabolism in Huh7 cells may be primarily mediated by IRS2. In HCV‑Huh7 cells, the downstream pathway of IRS2 is blocked, suggesting that this may be the underlying mechanism in HCV infection that leads to insulin resistance. The present findings add a further dimension to the understanding of the pathological mechanisms of HCV infection-associated insulin resistance, and provide novel concepts for insulin resistance and glucose metabolism research.

Chronic hepatitis C virus (HCV) burden in Rhode Island: modelling treatment scale-up and elimination

We utilized a disease progression model to predict the number of viraemic infections, cirrhotic cases, and liver-related deaths in the state of Rhode Island (RI) under four treatment scenarios: (1) current HCV treatment paradigm (about 215 patients treated annually, Medicaid reimbursement criteria fibrosis stage ⩾F3); (2) immediate scale-up of treatment (to 430 annually) and less restrictive Medicaid reimbursement criteria (fibrosis stage ⩾F2); (3) immediate treatment scale-up and no fibrosis stage-specific Medicaid reimbursement criteria (⩾F0); (4) an 'elimination' scenario (i.e. a continued treatment scale-up needed to achieve >90% reduction in viraemic cases by 2030). Under current treatment models, the number of cirrhotic cases and liver-related deaths will plateau and peak by 2030, respectively. Treatment scale-up with ⩾F2 and ⩾F0 fibrosis stage treatment criteria could reduce the number of cirrhotic cases by 21·7% and 10·0%, and the number of liver-related deaths by 19·3% and 7·4%, respectively by 2030. To achieve a >90% reduction in viraemic cases by 2030, over 2000 persons will need to be treated annually by 2020. This strategy could reduce cirrhosis cases and liver-related deaths by 78·9% and 72·4%, respectively by 2030. Increased HCV treatment uptake is needed to substantially reduce the burden of HCV by 2030 in Rhode Island.

New treatments for hepatitis C virus (HCV): scope for preventing liver disease and HCV transmission in England

New direct-acting antivirals have the potential to transform the hepatitis C (HCV) treatment landscape, with rates of sustained viral response in excess of 90%. As these new agents are expensive, an important question is whether to focus on minimizing the consequences of severe liver disease, or reducing transmission via 'treatment as prevention'. A back-calculation model was used to estimate the impact of treatment of mild, moderate and compensated cirrhosis on incident cases of HCV-related end-stage liver disease/hepatocellular carcinoma (ESLD/HCC). In addition, a dynamic model was used to determine the impact on incidence and prevalence of chronic infection in people who inject drugs (PWID), the main risk group in England. Treating 3500 cirrhotics per year was predicted to reduce ESLD/HCC incidence from 1100 (95% CrI 970-1240) cases per year in 2015 to 630 (95% CrI 530-770) in 2020, around half that currently expected, although treating moderate-stage disease will also be needed to sustain this reduction. Treating mild-stage PWID was required to make a substantial impact on transmission: with 2500 treated per year, chronic prevalence/annual incidence in PWID was reduced from 34%/4.8% in 2015 to 11%/1.4% in 2030. There was little overlap between the two goals: treating mild stage had virtually no impact on ESLD/HCC within 15 years, but the long timescale of liver disease means relatively few PWID reach cirrhosis before cessation of injecting. Strategies focussing on treating advanced disease have the potential for dramatic reductions in severe morbidity, but virtually no preventative impact.

Is psychosocial and cognitive dysfunction misattributed to the virus in hepatitis C infection? Select psychosocial contributors identified

Chronic hepatitis C is associated with health-related quality of life and cognitive impairments, even in mild disease. Recent evidence demonstrating hepatitis C virus (HCV) neurotropism has strengthened a neuropathophysiological hypothesis. However, sample heterogeneity confounds study outcomes. A uniquely homogeneous cohort of Irish women, following an iatrogenic HCV outbreak, offers a rare opportunity to control for HCV chronicity and the virus' purported impact on quality of life and cognition. A multi site, three-group, cross-sectional design was employed. Noncirrhotic, iatrogenically infected women, developing either acute or chronic infection, were recruited from prospective tertiary-care liver clinics and the community. Well-matched healthy controls were also recruited. All participants completed a psychosocial survey and were invited to undergo a comprehensive neuropsychological test battery. Significantly distressed psychosocial symptom profiles were observed in those with an iatrogenic HCV exposure history, which was independent of viral chronicity. Chronic and cleared HCV cohorts were not differentiated from each other. Two distinct subgroups, demarcated along 'impaired' vs 'nonimpaired' quality-of-life reports, were clearly identified and logistic regression analysis identified depressed mood and cognitive fatigue, rather than viral status, as statistically significant predictors of group membership. Compared with matched controls, significant cognitive impairments were not observed in either HCV cohort. Our findings provide strong evidence of nonviral factors accounting for quality of life impairment in chronic HCV and they also appear to question existing reports of cognitive dysfunction in mild disease. Depressed mood and cognitive fatigue appear to be critical psychosocial mediators of reduced quality-of-life and we hypothesize that metabolite abnormalities reported in HCV samples may also be confounded by these factors, given the associated literature.

Factors associated with spontaneous clearance of chronic hepatitis C virus infection

BACKGROUND & AIMS

Spontaneous clearance of chronic hepatitis C virus (HCV) infection (CHC) is rare. We conducted a retrospective case-control study to identify rates and factors associated with spontaneous clearance of CHC.

METHODS

We defined cases as individuals who spontaneously resolved CHC, and controls as individuals who remained chronically infected. We used data obtained on HCV testing between 1994 and 2013 in the West of Scotland to infer case/control status. Specifically, untreated patients with ⩾2 sequential samples positive for HCV RNA ⩾6months apart followed by ⩾1 negative test, and those with ⩾2 positive samples ⩾6months apart with no subsequent negative samples were identified. Control patients were randomly selected from the second group (4/patient of interest). Case notes were reviewed and patient characteristics obtained.

RESULTS

25,113 samples were positive for HCV RNA, relating to 10,318 patients. 50 cases of late spontaneous clearance were identified, contributing 241 person-years follow-up. 2,518 untreated, chronically infected controls were identified, contributing 13,766 person-years follow-up, from whom 200 controls were randomly selected. The incidence rate of spontaneous clearance was 0.36/100 person-years follow-up, occurring after a median 50months' infection. Spontaneous clearance was positively associated with female gender, younger age at infection, lower HCV RNA load and co-infection with hepatitis B virus. It was negatively associated with current intravenous drug use.

CONCLUSIONS

Spontaneous clearance of CHC occurs infrequently but is associated with identifiable host and viral factors. More frequent HCV RNA monitoring may be appropriate in selected patient groups.

LAY SUMMARY

Clearance of hepatitis C virus infection without treatment occurs rarely once chronic infection has been established. We interrogated a large Scottish patient cohort and found that it was more common in females, patients infected at a younger age or with lower levels of HCV in the blood, and patients co-infected with hepatitis B virus. Patients who injected drugs were less likely to spontaneously clear chronic infection.

Prevalence and burden of HCV co-infection in people living with HIV: a global systematic review and meta-analysis

BACKGROUND

At global level, there are 37 million people infected with HIV and 115 million people with antibodies to hepatitis C virus (HCV). Little is known about the extent of HIV-HCV co-infection. We sought to characterise the epidemiology and burden of HCV co-infection in people living with HIV.

METHODS

In this systematic review and meta-analysis we searched MEDLINE, Embase, CINAHL+, POPLINE, Africa-wide Information, Global Health, Web of Science, and the Cochrane Library and WHO databases for studies measuring prevalence of HCV and HIV, published between Jan 1, 2002, and Jan 28, 2015. We included studies in HIV population samples of more than 50 individuals and recruited patients based on HIV infection status or other behavioural characteristics. We excluded editorials or reviews containing no primary data, samples of HCV or HIV-HCV co-infected individuals, or samples relying on self-reported infection status. We also excluded samples drawn from populations with other comorbidities or undergoing interventions that put them at increased risk of co-infection. Populations were categorised according to HIV exposure, with the regional burden of co-infection being derived by applying co-infection prevalence estimates to published numbers of HIV-infected individuals. We did a meta-analysis to estimate the odds of HCV in HIV-infected individuals compared with their HIV-negative counterparts.

FINDINGS

From 31 767 citations identified, 783 studies met the inclusion criteria, resulting in 902 estimates of the prevalence of HIV-HCV co-infection. In HIV-infected individuals, HIV-HCV co-infection was 2·4% (IQR 0·8-5·8) within general population samples, 4·0% (1·2-8·4) within pregnant or heterosexually exposed samples, 6·4% (3·2-10·0) in men who have sex with men (MSM), and 82·4% (55·2-88·5) in people who inject drugs (PWID). Odds of HCV infection were six times higher in people living with HIV (5·8, 95% CI 4·5-7·4) than their HIV-negative counterparts. Worldwide, there are approximately 2 278 400 HIV-HCV co-infections (IQR 1 271 300-4 417 000) of which 1 362 700 (847 700-1 381 800) are in PWID, equalling an overall co-infection prevalence in HIV-infected individuals of 6·2% (3·4-11·9).

INTERPRETATION

We noted a consistently higher HCV prevalence in HIV-infected individuals than HIV-negative individuals  across all risk groups and regions, but especially in PWID. This study highlights the importance of routine HCV testing in all HIV-infected individuals, but especially in PWID. There is also a need to improve country-level surveillance of HCV prevalence across different population groups in all regions.

FUNDING

WHO.