Spread Times of Hepatitis C Virus Estimated by the Molecular Clock Differ among Japan, the United States and Egypt in Reflection of Their Distinct Socioeconomic Backgrounds

Epidemiology of viral hepatitis C: Road to elimination in Japan

Although HCV infection was the main cause of HCC in Japan contributing 70% over two decades after its first cloning in 1989, it was markedly decreased to 49% in 2013 and expected to decrease continuously. Based on blood donor national database, the new incident cases were 0.4/100,000 person-years, the prevalence was 0.13% and the total number was 890,902-1,302,179 in 2015. Establishment of blood donor screening with anti-HCV measurement and nucleic acid test introduced by Japanese Red Cross as pioneer, high-level medical and surgical care, and the government's policy under the Basic Act on Hepatitis Control have changed its epidemiology and outbreak trend and also enforced the disruption of potential transmission cascades. HCV prevalence among the younger generation was extremely low in all regions, and the predominant age for HCC has shifted to over 60 years old population. Considering such changes, HCV induced HCC occurrence is supposed to be ultimately suppressed in the near future. However, taking into account society changes, regulating intravenous drugs users and monitoring high-risk groups such as tattoos, and men who have sex with men are indeed required in Japan. Understanding the epidemiological changes in HCV is important in assigning, modifying, and designating effective response systems. Selective or national action plans, strategic approaches, and cooperation between government sectors have a positive impact on HCV prevention and control. A dramatic decrease in total number of HCV carriers, increase in number of people treated with highly effective DAA, and subsequent high SVR indicates Japan might achieve WHO's target of HCV elimination by 2030.

Ledipasvir-sofosbuvir for treating Japanese patients with chronic hepatitis C virus genotype 2 infection

BACKGROUND & AIMS

Japanese patients with chronic hepatitis C virus (HCV) genotype 2 infection have high rates of sustained virological response (SVR) following 12 weeks of treatment with the nucleotide polymerase inhibitor sofosbuvir in combination with ribavirin, which was the standard of care at the time this study was undertaken. We assessed the efficacy of 12 weeks of treatment with a ribavirin-free regimen of ledipasvir-sofosbuvir.

METHODS

In an open-label, Phase 3 trial we enrolled Japanese patients with chronic HCV genotype 2 infection, with or without compensated cirrhosis. In Cohort 1, participants were randomized 1:1 to receive ledipasvir-sofosbuvir (n = 106) or sofosbuvir + ribavirin (n = 108) for 12 weeks. In Cohort 2, 25 ribavirin-intolerant or -ineligible patients received ledipasvir-sofosbuvir for 12 weeks. The primary endpoint was SVR 12 weeks after therapy (SVR12). In Cohort 1 non-inferiority was assessed with a prespecified margin of 10%.

RESULTS

One-third (33%) of patients were treatment experienced, and 14% had cirrhosis. In Cohort 1, SVR12 rates were 96% (95% CI, 91% to 99%) with ledipasvir-sofosbuvir and 95% (95% CI, 90% to 98%) with sofosbuvir plus ribavirin, thus achieving non-inferiority. Among ribavirin-intolerant/ineligible patients in Cohort 2, SVR12 was 96% (95% CI, 80% to 100%) with ledipasvir-sofosbuvir. Overall, the most common adverse events were nasopharyngitis, anaemia, and headache; anaemia was only observed in patients receiving ribavirin. The percentage of patients who discontinued treatment because of an adverse event was low (1%).

CONCLUSIONS

Among Japanese patients with HCV genotype 2, 12 weeks of treatment with ledipasvir-sofosbuvir resulted in high rates of SVR12 that were non-inferior to sofosbuvir + ribavirin.

Efficacy and safety of glecaprevir/pibrentasvir in Japanese patients with chronic genotype 2 hepatitis C virus infection

Glecaprevir (nonstructural protein 3/4A protease inhibitor) and pibrentasvir (nonstructural protein 5A inhibitor) (G/P), a coformulated once-daily, all oral, ribavirin (RBV)-free, direct-acting antiviral regimen, was evaluated for safety and efficacy in hepatitis C virus genotype 2 (GT2)-infected Japanese patients, including those with compensated cirrhosis. CERTAIN-2 is a phase 3, open-label, multicenter study assessing the safety and efficacy of G/P (300/120 mg) once daily in treatment-naive and interferon ± RBV treatment-experienced Japanese patients without cirrhosis but with GT2 infection. Patients were randomized 2:1 to receive 8 weeks of G/P (arm A) or 12 weeks of sofosbuvir (400 mg once daily) + RBV (600-1000 mg weight-based, twice daily) (arm B). The primary endpoint was noninferiority of G/P compared to sofosbuvir + RBV by assessing sustained virologic response at posttreatment week 12 (SVR12) among patients in the intent-to-treat population. SVR12 was also assessed in treatment-naive and interferon ± RBV treatment-experienced patients with GT2 infection and compensated cirrhosis who received G/P for 12 weeks in the CERTAIN-1 study. A total of 136 patients were enrolled in CERTAIN-2. SVR12 was achieved by 88/90 (97.8%) patients in arm A and 43/46 (93.5%) patients in arm B. No patient in arm A experienced virologic failure, while 2 did in arm B. The primary endpoint was achieved. In CERTAIN-1, 100% (18/18) of GT2-infected patients with compensated cirrhosis achieved SVR12. Treatment-emergent serious adverse events were experienced by 2 patients without cirrhosis in each arm and no patient with cirrhosis. Conclusion: The results demonstrate high efficacy and favorable tolerability of G/P in GT2-infected Japanese patients. (Hepatology 2018;67:505-513).

Effectiveness and safety of community-based treatment with sofosbuvir plus ribavirin for elderly patients with genotype 2 chronic hepatitis C

BACKGROUND

The aim of this study was to clarify the effectiveness and safety of sofosbuvir/ribavirin therapy for elderly patients with genotype 2-infected chronic hepatitis C (CHC) in Japan.

METHODS

A multicenter, retrospective study evaluated the effectiveness and safety of sofosbuvir/ribavirin based on real-world clinical data.

RESULTS

The subjects consisted of 270 patients, 47.0% of whom were aged ≥65 years. The sustained virological response rates in patients aged <65 and ≥65 years were 98.6% and 95.3%, respectively. Hemoglobin levels decreased during treatment due to ribavirin-related hemolysis, and were significantly lower in patients aged ≥65 years than those aged <65 years at all time-points. A reduction in ribavirin dose was necessary in 31.0% (26/84) of patients with hemoglobin levels <13.0g/dL and in 70.7% (39/127) of those aged >65 years. Although the most frequent adverse event was anemia, no patients discontinued the use of either ribavirin or sofosbuvir. The incidence of ribavirin-related anemia in patients aged ≥65 years was 34.6% and significantly higher compared with that in patients aged <65 years (2.8%).

CONCLUSIONS

Treatment with sofosbuvir/ribavirin for genotype 2-infected CHC was effective and safe even for elderly patients, although the incidence of adverse events including ribavirin-related anemia was relatively high.

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.

Assessing the Budget Impact and Economic Outcomes of the Introduction of Daclatasvir + Asunaprevir and Sofosbuvir/Ledipasvir for the Treatment of Chronic Hepatitis C Virus Infection in Japan

BACKGROUND

The advent of highly efficacious, well-tolerated, all-oral direct-acting antiviral regimens has revolutionized the standard of care for patients chronically infected with hepatitis C virus. As efficacy and safety rates converge, prescribers and payers need to consider value for money.

OBJECTIVES

To evaluate the health economic value of daclatasvir + asunaprevir versus sofosbuvir/ledipasvir via a cost-effectiveness analysis, and determine the optimal treatment considering both costs and health outcomes in Japan.

METHODS

A previously published Markov model was used to estimate the cost-effectiveness of daclatasvir + asunaprevir compared with sofosbuvir/ledipasvir on the basis of a matching-adjusted indirect comparison of pivotal trials and modeling inputs specific to the Japanese setting. A de novo budget impact model was developed and used to predict the cost implications of differing treatment sequences.

RESULTS

Cost-effectiveness results demonstrated minimal difference in terms of benefit (0.037 fewer QALYs and 0.014 fewer life-years with daclatasvir + asunaprevir); nevertheless, a significant difference in cost was predicted (estimated ¥2,299,700 [US $21,695] reduction with daclatasvir + asunaprevir). The budget impact analysis estimated that treatment with daclatasvir + asunaprevir is expected to be less expensive than treatment with sofosbuvir/ledipasvir (as the proportion of patients initially treated with sofosbuvir/ledipasvir increased from 0% to 100%, total costs increased from ¥206 to ¥403 billion [US $1.94 billion to US $3.80 billion]).

CONCLUSIONS

On the basis of results from an established cost-effectiveness model and a conventional budget impact analysis, treatment with daclatasvir + asunaprevir is expected to be cost-saving compared with treatment with sofosbuvir/ledipasvir in Japan with similar health outcomes, regardless of treatment sequence.

Comparison of Daclatasvir and Asunaprevir for Chronic HCV 1b Infection with Telaprevir and Simeprevir plus Peginterferon and Ribavirin, with a Focus on the Prevention of Occurrence and Recurrence of Hepatocellular Carcinoma

OBJECTIVES

The efficacy of the all-oral administration of daclatasvir and asunaprevir for 24 weeks was compared with that of telaprevir for 12 weeks plus pegylated interferon and ribavirin (PEG-IFN/RBV) for 24 weeks, and that of simeprevir for 12 weeks plus PEG-IFN/RBV for 24 weeks, with a focus on the prevention of occurrence and recurrence of hepatocellular carcinoma (HCC). The levels of alanine aminotransferase (ALT) and α-fetoprotein (AFP) as suppressive markers of HCC were also measured.

METHODS

Patients received daclatasvir and asunaprevir (n = 17), simeprevir plus PEG-IFN/RBV (n = 15) and telaprevir plus PEG-IFN/RBV (n = 25). Sustained virological response (SVR) and the mean change in the level of serum ALT, AFP and platelet (PLT) count were compared among the three groups.

RESULTS

No difference in SVR was observed in patients given daclatasvir with asunaprevir (SVR4), telaprevir plus PEG-IFN/RBV or simeprevir plus PEG-IFN/RBV (SVR24). Also, no significant difference was observed in the mean change of serum ALT, AFP or PLT count among the three groups.

CONCLUSION

The preventive effect of the IFN-free, all-oral regimen of daclatasvir and asunaprevir was observed with a focus on the occurrence and recurrence of HCC, as was IFN-based treatment with telaprevir or simeprevir plus PEG-IFN/RBV.

New insight into HCV E1/E2 region of genotype 4a

Introduction

Hepatitis C virus (HCV) genome contains two envelope proteins (E1 and E2) responsible for the virus entry into the cell. There is a substantial lack of sequences covering the full length of E1/E2 region for genotype 4. Our study aims at providing new sequences as well as characterizing the genetic divergence of the E1/E2 region of HCV 4a using our new sequences along with all publicly available datasets.

Methods

The genomic segments covering the whole E1/E2 region were isolated from Egyptian HCV patients and sequenced. The resulting 36 sequences 36 were analyzed using sequence analysis techniques to study variability within and among hosts in the same time point. Furthermore, previously published HCV E1/E2 sequence datasets for genotype 4a were retrieved and categorized according to the geographical location and date of isolation and were used for further analysis of variability among Egyptian over a period of 15 years, also compared with non-Egyptian sequences to figure out region-specific variability.

Results

Phylogenetic analysis of the new sequences has shown variability within the host and among different individuals in the same time point. Analysis of the 36 sequences along with the Egyptian sequences (254 sequences in E1 in the period from 1997 to 2010 and 8 E2 sequences in the period from 2006 to 2010) has shown temporal change over time. Analysis of the new HCV sequences with the non-Egyptian sequences (182 sequences in E1 and 155 sequences in the E2) has shown region specific variability. The molecular clock rate of E1 was estimated to be 5E-3 per site per year for Egyptian and 5.38E-3 for non-Egyptian. The clock rate of E2 was estimated to be 8.48E per site per year for Egyptian and 6.3E-3 for non-Egyptian.

Conclusion

The results of this study support the high rate of evolution of the Egyptian HCV genotype 4a. It has also revealed significant level of genetic variability among sequences from different regions in the world.

Electronic supplementary material

The online version of this article (doi:10.1186/s12985-014-0231-y) contains supplementary material, which is available to authorized users.

Sofosbuvir plus ribavirin in Japanese patients with chronic genotype 2 HCV infection: an open-label, phase 3 trial

Genotype 2 hepatitis C virus (HCV) accounts for up to 30% of chronic HCV infections in Japan. The standard of care for patients with genotype 2 HCV - peginterferon and ribavirin for 24 weeks - is poorly tolerated, especially among older patients and those with advanced liver disease. We conducted a phase 3, open-label study to assess the efficacy and safety of an all-oral combination of the NS5B polymerase inhibitor sofosbuvir and ribavirin in patients with chronic genotype 2 HCV infection in Japan. We enrolled 90 treatment-naïve and 63 previously treated patients at 20 sites in Japan. All patients received sofosbuvir 400 mg plus ribavirin (weight-based dosing) for 12 weeks. The primary endpoint was sustained virologic response at 12 weeks after therapy (SVR12). Of the 153 patients enrolled and treated, 60% had HCV genotype 2a, 11% had cirrhosis, and 22% were over the aged 65 or older. Overall, 148 patients (97%) achieved SVR12. Of the 90 treatment-naïve patients, 88 (98%) achieved SVR12, and of the 63 previously treated patients, 60 (95%) achieved SVR12. The rate of SVR12 was 94% in patients with cirrhosis and in those aged 65 and older. No patients discontinued study treatment due to adverse events. The most common adverse events were nasopharyngitis, anaemia and headache. Twelve weeks of sofosbuvir and ribavirin resulted in high rates of SVR12 in treatment-naïve and previously treated patients with chronic genotype 2 HCV infection. The treatment was safe and well tolerated by patients, including the elderly and those with cirrhosis.

Transmission dynamics of hepatitis C virus among intra venous drug users in the border state of Manipur, India

Intra venous drug users (IVDUs) are at high risk for hepatitis C virus (HCV) infection owing to their high rate of drug abuses. The north-eastern part of India has a high prevalence of IVDUs with Manipur being the worst hit state. The aim of the study was to document the molecular epidemiology, the patterns of HCV transmission, genomic variation and recombination events within HCV genome among IVDUs of Manipur, India. 91 anti-HCV sero-reactive blood samples were collected from IVDUs in Manipur. The samples were processed for RNA extraction, nested RT-PCR, sequencing and quantitative viral RNA estimation. Phylogeographic analysis of the sequenced core and NS5B regions of HCV genome was performed to determine the probable transmission route and recombinant HCV strains. 83 out of 91 anti-HCV seropositive samples were RNA positive (91.20%) based on 5'UTR of HCV genome by nested RT-PCR. Of the RNA positive samples, 73 paired partial core and NS5B gene were sequenced. Three major genotype and eight subtypes were detected while no recombinant strains were found. Individuals with genotype 1 had the mean viral load (5.94 ± 0.705 log10IU/ml) followed by genotype 3 (4.91 ± 0.49 log10IU/ml) and 6 (3.96 ± 0.32 log10IU/ml). The viral load was statistically significant among the male individuals at 4.822 ± 1.36 log10IU/ml compared to 4.767 ± 0.49 log10IU/ml for females (t=3.249, p<0.005). The phylogeographic results indicated 3b, 6h originated from Vietnam, 1a had Indian origin, 3a, 6k originated from southern China while 1b originated from Myanmar, respectively. The incidence of eight different subtypes in Manipur reflects the transmission of these strains from the "Golden Triangle" drug trafficking regions. Sequence analysis confirmed the transmission routes of HCV, which is linked to China and Vietnam for the newly emergent genotype 6 in north-eastern India.

The origin of hepatitis C virus

The origin of hepatitis C virus (HCV) can be conceptualised at several levels. Firstly, origins might refer to its dramatic spread throughout the Western world and developing countries throughout the twentieth century. As a blood-borne virus, this epidemic was fuelled by new parenteral transmission routes associated with medical treatments, immunisation, blood transfusion and more recently injecting drug use. At another level, however, origins might refer to the immediate sources of HCV associated with its pandemic spread, now identified as areas in Central and West sub-Saharan Africa and South and South East Asia where genetically diverse variants of HCV appear to have circulated for hundreds of years. Going back a final step to the actual source of HCV infection in these endemic areas, non-human primates have been long suspected as harbouring viruses related to HCV with potential cross-species transmission of variants corresponding to the 7 main genotypes into humans. Although there is tempting analogy between this and the clearly zoonotic origin of HIV-1 from chimpanzees in Central Africa, no published evidence to date has been obtained for infection of HCV-like viruses in either apes or Old World monkey species. Indeed, a radical re-think of both the host range and host-specificity of hepaciviruses is now required following the very recent findings of a non-primate hepacivirus (NPHV) in horses and potentially in dogs. Further research on a much wider range of mammals is needed to better understand the true genetic diversity of HCV-like viruses and their host ranges in the search for the ultimate origin of HCV in humans.

Molecular epidemiology and genetic history of hepatitis C virus subtype 3a infection in Thailand

OBJECTIVE

Among all hepatitis C virus (HCV) infections, subtype 3a is the most common genotype in Thailand. This study investigates the molecular epidemiology and epidemic history of HCV subtype 3a in Thailand.

METHODS

Three hundred and fifty-six serum samples were collected from HCV-infected Thai patients. The virus was isolated, after which the core and NS5B regions were sequenced. Subsequently, the HCV genotype was classified by phylogenetic analysis based on the core and NS5B regions. Molecular evolution analysis of HCV subtype 3a was estimated using BEAST (Bayesian Evolutionary Analysis by Sampling Trees) v.1.5.4.

RESULTS

Based on our phylogenetic analyses, subtype 3a (38.5%) was the most prevalent, followed by 1a (21%), 1b (13.8%), genotype 6 (19.9%) [comprised of subtypes 6e (0.3%), 6f (11%), 6i (1.9%), 6j (1.9%) and 6n (4.8%)] and 3b (5.6%). Our phylogenetic tree indicates the existence of a specific group of HCV subtype 3a strains in the Thai population. Molecular evolutionary analysis dated the most recent common ancestor of the Thai HCV subtype 3a strains as existing approximately 200 ago, and a Bayesian skyline plot showed that this particular strain spread to Thailand during the mid-1970s and early 1980s. This period overlaps with the Vietnam War (1955-1975) and the widespread use of injection stimulants introduced by the US Army during this time.

CONCLUSION

The estimated history of HCV subtype 3a infection in Thailand may help to predict the future burden of HCV-related diseases and facilitate better public health control and surveillance.

Can brucellosis influence the course of chronic hepatitis C in dual infection?

Hepatitis C and brucellosis are infectious diseases that occur worldwide, and both are endemic in Egypt. Co-infection with both agents is possible, and this can involve the liver in various ways. In this study, we investigated serum tissue inhibitor metalloproteinase-1 (TIMP-1), viral load, and liver functions in patients co-infected with hepatitis C virus (HCV) before and after brucellosis treatment. Over 3 years, 241 consecutive HCV patients (before interferon therapy was received) with recurrent fever who had occupational contact with animals were tested for brucellosis co-infection by a standard tube agglutination test. In patients with dual infection, viraemia (RT-PCR), TIMP-1 measured by ELISA, and liver functions were assessed and re-evaluated 2 months after brucellosis treatment. The number of patients with HCV/brucellosis co-infection was 32 out of 241 (13.3%). TIMP-1, viraemia, AST, ALT and bilirubin showed significant decrease (improvement) after brucellosis treatment (p < 0.001) but an insignificant difference (p > 0.05) with regard to serum albumin and prothrombin concentration. The study revealed that brucellosis is an important infection in HCV-infected patients and can aggravate the course of disease, suggesting that early treatment and prevention are important.

Hepatitis C viremia and genotype distribution among a sample of nonmedical prescription drug users exposed to HCV in rural Appalachia

Research has demonstrated that hepatitis C (HCV) genotype distribution varies geographically and demographically. This exploratory study examines HCV viremia, viral concentration, and genotype distribution among anti-HCV positive, rural Appalachian nonmedical prescription drug users. The study population was randomly selected from a pool of 200 anti-HCV positive participants in a longitudinal study. Those randomly chosen were representative of the overall pool in terms of demographics, drug use, and other risk behaviors. Participants were tested serologically for HCV RNA, viral concentration, and genotype, and interview-administered questionnaires examined behavioral and demographic characteristics. Of the 81 participants, 69% tested RNA positive, 59% of which had viral loads exceeding 800,000 IU/ml. Approximately 66% of the RNA positive sample had genotype 1a; types 2b (16%) and 3a (13%) were less common. RNA positive participants were not significantly different than RNA negative participants demographically or behaviorally. Likewise, with the exception of education, genotype 1 participants were not significantly different than those with genotype 2 or 3. The prevalence of active HCV infection highlights a need for prevention and treatment in this population. However, the predominance of genotype 1 may present challenges due to its association with decreased responsiveness to drug treatment, although the novel class of direct-acting antivirals such as telaprevir and boceprevir offer new hope in this regard. The prevalence of genotype 1 may also foreshadow heightened burden of hepatocellular carcinoma and elevated healthcare expenditures. More research is needed to characterize HCV infection and genotype in this population.

Colonial history and contemporary transmission shape the genetic diversity of hepatitis C virus genotype 2 in Amsterdam

Evolutionary analysis of hepatitis C virus (HCV) genome sequences has provided insights into the epidemic history and transmission of this widespread human pathogen. Here we report an exceptionally diverse set of 178 HCV genotype 2 (HCV-2) isolates from 189 patients in Amsterdam, comprising 8 distinct HCV subtypes and 10 previously not recognized, unclassified lineages. By combining study subjects' demographic information with phylogeographic and molecular clock analyses, we demonstrate for the first time that the trans-Atlantic slave trade and colonial history were the driving forces behind the global dissemination of HCV-2. We detect multiple HCV-2 movements from present-day Ghana/Benin to the Caribbean during the peak years of the slave trade (1700 to 1850) and extensive transfer of HCV-2 among the Netherlands and its former colonies Indonesia and Surinam over the last 150 years. The latter coincides with the bidirectional migration of Javanese workers between Indonesia and Surinam and subsequent immigration to the Netherlands. In addition, our study sheds light on contemporary trends in HCV transmission within the Netherlands. We observe multiple lineages of the epidemic subtypes 2a, 2b, and 2c (together 67% of HCV-2 infections in Amsterdam), which cluster according to their suspected routes of transmission, specifically, injecting drug use (IDU) and contaminated blood/blood products. Understanding the epidemiological processes that generated the global pattern of HCV diversity seen today is critical for exposing associations between populations, risk factors, and specific HCV subtypes and might help HCV screening and prevention campaigns to minimize the future burden of HCV-related liver disease.

Hepatitis C virus infection in a Japanese leprosy sanatorium for the past 67 years

Oku-Komyo-En is one of the national leprosy sanatoria, located on a small island in Setouchi city, Okayama prefecture of Japan since 1938. Since autopsies were carried out routinely on almost all patients who had died in the sanatorium up to 1980, approximately 1,000 formalin-fixed autopsy tissue samples were available for analysis. When these samples were reviewed, the pathological data indicated a sharp rise in the death rate caused by cirrhosis of the liver and hepatocellular carcinoma (HCC) since 1960 and 1970, respectively. Hepatitis C virus (HCV) infection is a common cause of HCC in Japan. The presence of HCV RNA was demonstrated in paraffin sections prepared from the autopsied liver tissue fixed in formalin for a prolonged period of time, by employing nested RT-PCR using type-specific primers. The data showed that HCV RNA was detectable in samples of the liver archived as early as 1940, representing the liver tissues kept in formalin for up to 67 years. HCV genotypes 1b and 2a were found by RT-PCR at 85.7% and 14.3%, respectively, in patients with leprosy.

Phylogeography and molecular epidemiology of hepatitis C virus genotype 2 in Africa

Understanding the origin and nature of hepatitis C virus (HCV) genetic diversity is critical for improving treatment and vaccine design, and such diversity is the sole source of information about the virus' epidemic history prior to its identification 20 years ago. In this paper, we study the molecular epidemiology of HCV genotype 2 in its region of endemic origin, west and central Africa. Our analysis includes 56 new and highly diverse HCV isolates sampled from infected individuals in Guinea-Bissau. By combining phylogenetic, geographical and epidemiological information, we find a previously unappreciated geographical structure in the diversity of HCV genotype 2, pointing to a history of eastwards spatial spread from the west African coast to Cameroon that took place over several centuries. Molecular clock analysis dates the common ancestor of HCV in Guinea-Bissau to 1470 (1414-1582). The phylogenetic position of isolates from Madagascar and Martinique suggests a role for the historical slave trade in the global dissemination of HCV and of the epidemic subtypes 2a and 2c. Coalescent-based estimates of epidemic growth indicate a rapid 20th-century spread of HCV genotype 2 in Cameroon that is absent in Guinea-Bissau. We discuss this contrast in the context of possible parenteral HCV exposure during public-health campaigns undertaken during the colonial era.

HCV genetic variability: from quasispecies evolution to genotype classification

HCV is a ssRNA virus belonging to the Flaviviruses and is found worldwide worldwide in humans. Following primary infection, persistent infection develops in more than 85% of cases, which in up to 30% of cases, may progress to liver disease, cirrhosis and hepatocellular carcinoma. The virus presents a high degree of genetic variability owing to the combination of a lack of proofreading by the RNA-dependent RNA polymerase and a high level of viral replication. This genetic variability allows the classification of genotypes, subtypes, isolates and quasispecies to which epidemiological and pathogenetic significance may be associated. The features and biological implications of HCV variability and of quasispecies dynamics in infection transmission, mechanisms of chronicity and resistance to antiviral therapy are discussed.

The emerging importance of chronic hepatitis C infection in Asian Americans

OBJECTIVES

To study the demographics, epidemiology, and natural history of chronic hepatitis C in Asian Americans.

METHODS

This retrospective survey describes 260 Asian Americans with chronic hepatitis C referred to one tertiary center.

RESULTS

Ninety-two percent of patients were born in Asia. Fifty-one percent reported a history of unsafe therapeutic injections, which was a risk factor only in those with exposure outside the United States (p < 0.0001). A history of transfusion was reported in 41% of patients and was more frequent in those with exposure within the Unites States (p < 0.0001). Only 3.8% reported a history of intravenous drug abuse, which was more frequent in those with exposure within the United States (p < 0.0001). Hepatitis C genotype 1 was detected in 64.2% of patients, genotype 2 in 18.3%, and genotype 6 in 11.3%. Genotype 1 had a significantly lower sustained virologic response rate (32.8%) to interferon treatment, compared with genotype 2 (77.8%) or 6 (69.2%). During a mean follow-up of 6 yr, 26 patients developed hepatocellular carcinoma (HCC). Logistic regression model revealed fibrosis stage 4 (odds ratio [OR] 8.87, 95% confidence interval [CI] 2.97-26.48, p < 0.0001), age at presentation (55 vs 35 yr--OR 3.45, 95% CI 1.22-9.75, p= 0.0194), and baseline albumin level (3.0 vs 4.0 mg/dL--OR 3.47, 95% CI 1.02-11.76, p= 0.0464) were independent predictive factors for HCC development.

CONCLUSIONS

Asian Americans with a history of unsafe therapeutic injections must be screened for chronic hepatitis C. Antiviral treatment should be initiated prior to development of cirrhosis. Surveillance for HCC must be routinely performed in cirrhosis patients.

Transmission of hepatitis C virus by blood transfusions and other medical procedures: a global review

Hepatitis C virus (HCV) is a leading cause of chronic blood-borne infection and chronic liver disease. The global epidemic of HCV infection emerged in the second half of the 20th century, and several lines of evidence indicate that it was primarily triggered and fed iatrogenically by the increasing use of parenteral therapies and blood transfusion. In developed countries, the rapid improvement of healthcare conditions and the introduction of anti-HCV screening for blood donors have led to a sharp decrease in the incidence of iatrogenic hepatitis C, but the epidemic continues to spread in developing countries, where the virus is still transmitted through unscreened blood transfusions and non-sterile injections. This article reviews the published literature concerning HCV transmission through blood transfusions and other unsafe medical procedures. Given the substantial difference in current disease transmission patterns between the northern and southern hemispheres, the situation in developed and developing countries is separately analysed.