Unexpected high prevalence of hepatitis C virus genotype 4 in Southern Spain

Changes in the epidemiology and distribution of the hepatitis C virus genotypes in North-Eastern Spain over the last 35 years

BACKGROUND

Genotypic distribution and epidemiology of HCV infection in Western Europe countries has changed over the last decades.

AIM

To establish the local genotypic profile and characterize the associated demographic variables.

MATERIAL AND METHOD

All the genotyping from 1988 to 2015 were considered. Associated demographic variables were included in logistic regression models. Genotyping was carried out with updated commercial kits.

RESULTS

Genotype 1b was the most prevalent (42.4%) followed by 1a (22.5%), 3 (18.6%), 4 (10.6%) and 2 (4.6%). The prevalence of 1a was higher in males, in patients younger than 45 and in intravenous drug users (IDU). 1b was more frequent in older than 45, with transfusion-associated and parenteral/nosocomial infections and in immigrants from Eastern Europe. Genotype 2 was highly prevalent in the postransfusional route (54.9%). Genotype 3 prevalence was high in males, in patients younger than 45, in IDU (69.3%) and in Asian and Eastern European immigrants. Genotype 4 was high in males, in patients younger than 45, and in IDU (63.5%). 1a, 3, 4 were the most prevalent genotypes in HIV-coinfected patients. There was a significant decline in genotype 1b and an increase in genotypes 3 and 4 over time.

CONCLUSIONS

There has been a decline of genotype 1b, associated with transfusion or parenteral/nosocomial infections, and increases in the prevalence of genotypes 1a, 3 and 4 associated with male gender and IDU, now the most prevalent infection route. Immigration contributed with genotype 2 infections from Africa and genotype 1b and 3 infections from Eastern Europe and Asia.

Prevalence and distribution of hepatitis C virus genotypes in Spain during the 2000-2015 period (the GEHEP 005 study)

We report the largest study on the prevalence and distribution of HCV genotypes in Spain (2000-2015), and we relate them with clinical, epidemiological and virological factors. Patients from 29 hospitals in 10 autonomous communities (Andalusia, Aragon, Castilla-Leon, Catalonia, Galicia, Canary Islands, Madrid Community, Valencian Community, Murcia Region and Basque Country) have been studied. Annual distribution of HCV genotypes and subtypes, as well as gender, age, transmission route, HIV and/or HBV coinfection, and treatment details were recorded. We included 48595 chronically HCV-infected patients with the following characteristics: median age 51 years (IQR, 44-58), 67.9% male, 19.1% HIV-coinfected, 23.5% HBV-coinfected. Parenteral transmission route was the most frequent (58.7%). Genotype distribution was 66.9% GT1 (24.9% subtype 1a and 37.9% subtype 1b), 2.8% GT2, 17.3% GT3, 11.4% GT4 and 0.1% GT5 and 0.02% GT6. LiPA was the most widely HCV genotyping test used (52.4%). HCV subtype 1a and genotypes 3 and 4 were closely associated with male gender, parenteral route of infection and HIV and HBV coinfection; in contrast, subtype 1b and genotype 2 were associated with female gender, nonparenteral route and mono-infection. Age was related to genotype distribution, and different patterns of distribution and biodiversity index were observed between different geographical areas. Finally, we describe how treatment and changes in transmission routes may have affected HCV genotype prevalence and distribution patterns. We present the most recent data on molecular epidemiology of hepatitis C virus in Spain. This study confirms that genotype distributions vary with age, sex, HIV and HBV coinfection and within geographical areas and epidemiological groups.

Geographic integration of hepatitis C virus: A global threat

AIM

To assess hepatitis C virus (HCV) geographic integration, evaluate the spatial and temporal evolution of HCV worldwide and propose how to diminish its burden.

METHODS

A literature search of published articles was performed using PubMed, MEDLINE and other related databases up to December 2015. A critical data assessment and analysis regarding the epidemiological integration of HCV was carried out using the meta-analysis method.

RESULTS

The data indicated that HCV has been integrated immensely over time and through various geographical regions worldwide. The history of HCV goes back to 1535 but between 1935 and 1965 it exhibited a rapid, exponential spread. This integration is clearly seen in the geo-epidemiology and phylogeography of HCV. HCV integration can be mirrored either as intra-continental or trans-continental. Migration, drug trafficking and HCV co-infection, together with other potential risk factors, have acted as a vehicle for this integration. Evidence shows that the geographic integration of HCV has been important in the global and regional distribution of HCV.

CONCLUSION

HCV geographic integration is clearly evident and this should be reflected in the prevention and treatment of this ongoing pandemic.

Injecting drug use: A vector for the introduction of new hepatitis C virus genotypes

Hepatitis C virus (HCV) genotypes’ monitoring allows real-time insight into the dynamic changes that occur in the global epidemiological picture of HCV infection. Intravenous drug use is currently the primary driver for HCV transmission in developed and developing countries. The distribution of HCV genotypes/subtypes differs significantly between people who inject drugs (PWID) and the general population. HCV genotypes that previously exhibited a limited geographical distribution (3a, 4) are becoming more prevalent in this high-risk group. Immigration from HCV-endemic countries and the evolving networks of HCV transmission in PWID influence HCV genotypes distribution in Europe. Social vulnerabilities (e.g., unemployment, homelessness, and limited access to social and healthcare insurances systems) are important triggers for illicit drug use, which increases the associated risks of HCV infection and the frequent emergence of less prevalent genotypes. Genotype/subtype determination bears important clinical consequences in the progression of liver disease, susceptibility to antiviral therapies and the emergence of resistance-associated variants. An estimated half of the chronically HCV-infected PWID are unaware of their infection, and only one in ten of those diagnosed enter treatment. Nevertheless, PWID exhibit high response rates to new antiviral regimens, and the level of HCV reinfection is unexpectedly low. The focus of the healthcare system must be on the early detection and treatment of infection, to avoid late presentations that are associated with high levels of viremia and liver fibrosis, which may diminish the therapeutic success rate.

Hepatitis C virus genotype 4 in England: diversity and demographic associations

HCV strains belonging to genotype 4 may be gaining endemicity across Continental Europe but the extent of their spread in the United Kingdom is unknown. Sera referred from patients attending hospitals in England between 2004 through 2008 were characterised. A total of 243 sera carried HCV genotype 4. The most common subtypes were 4a (33%) and 4d (35%). Compared to patients infected by 4d, those infected by 4a were 20 times more likely to be Middle Eastern than English, and those infected by non-4a/4d were older, tended to be female, and 50 or 12 times more likely to be Middle Eastern or South Asian, respectively, than English. Persons infected by 4d tended to be English rather than Middle Eastern or South Asian. One group of 4d strains clustered with strains reported from persons in Europe engaged in male homosexual activity. Surveillance of trends in the importation and subsequent spread of HCV genotype 4 and its subtypes is advocated.

Review article: the epidemiology and therapy of chronic hepatitis C genotypes 4, 5 and 6

BACKGROUND

The global burden of hepatitis C (HCV) infection is mostly found in Africa, the Middle East and Asia, where HCV genotypes 4, 5 and 6 are common. The literature on these genotypes is sparse and this synopsis will review characteristics of patients infected with these genotypes.

AIM

To review characteristics of patients infected with HCV genotypes 4, 5 and 6.

METHODS

PubMed search for 'hepatitis C' AND 'genotype 4', 'hepatitis C' AND 'genotype 5', and 'hepatitis C' AND 'genotype 6' was conducted and relevant articles were reviewed.

RESULTS

Intravenous drug use is generally responsible for HCV genotype 4 infection in developed countries, but unsafe medical practices cause most cases of HCV genotypes 4, 5 and 6 in endemic countries. The sustained virological response (SVR) rate for patients with HCV genotype 4 who receive pegylated interferon and ribavirin for 48 weeks ranges from 40% to 70% in various small studies. The SVR rate is in the 60-70% range for HCV genotype 5 and 70-80% range for HCV genotype 6 following 48 weeks with pegylated interferon and ribavirin. Preliminary data suggest that a shorter course of 24 weeks of pegylated interferon and ribavirin may be acceptable for HCV genotype 6, with an SVR rate of approximately 70%.

CONCLUSIONS

The current standard-of-care therapy for HCV genotypes 4, 5 and 6 is pegylated interferon and ribavirin for 48 weeks. A shorter course with 24 weeks of therapy may be considered for patients with genotype 6. Newer and much more effective therapies may be forthcoming in the next few years.

Epidemiological features and specificities of HCV infection: a hospital-based cohort study in a university medical center of Calabria region

The epidemiological status of HCV in Europe, and in particular in Mediterranean countries, is continuously evolving. The genotype distribution is related to improvement of healthcare conditions, expansion of intravenous drug use and immigration. We review and characterize the epidemiology of the distribution of HCV genotypes within Calabria, an area of Southern Italy. We focus on the pattern of distinct HCV genotype changes over the last 16 years; particularly subtype 1b and genotype 4. We collected data by evaluating a hospital-based cohort of chronic hepatitis C patients; in addition, we report an update including new patients enrolled during last eight months.

The future for the treatment of genotype 4 chronic hepatitis C

Hepatitis C virus genotype 4 (HCV-4) is the most common type of hepatitis C virus (HCV) in the Middle East and Africa, in particular Egypt. Since the development of new protease inhibitors, the response of HCV-4 to the standard regimen of treatment (pegylated interferon/ribavirin) lags behind other genotypes and has become the most resistant type to treat. The development of therapeutic strategies for all patients with HCV-4 whether they are naïve, have experienced a virological breakthrough, are relapsers or non-responders is still a considerable challenge. New types of interferon (Consensus Interferon, Y-shaped, Albinterferon...) and new direct action antiviral drugs (Nitazoxanide, Vit.D, other) may improve the treatment of patients with HCV-4. The IL28B CC polymorphism may be associated with sustained virological response.

Molecular and epidemiological profiles of hepatitis C virus genotype 4 in Denmark

The prevalence of hepatitis C virus (HCV) genotype 4 has increased throughout Europe. This is an epidemiological study of patients infected chronically with HCV genotype 4 in Denmark. The HCV strains analyzed originated from patient samples collected between 1999 and 2007 as part of the national Danish hepatitis B and C network, DANHEP. Sequence analyses were based on the envelope 1 region of HCV. Results from a total of 72 patients indicated a high degree of genetic heterogeneity. Fifty-six patients (78%) were infected with one of the three dominating subtypes: 4d, 4a, or 4r. The remaining 16 patients (22%) were infected with subtypes 4h, 4k, 4l, 4n, 4o, or 4Unclassified. Three epidemiological profiles were identified: (1) patients infected with HCV by intravenous drug use were infected solely with subtype 4d. They were all of European origin, and 15 of the 16 patients were ethnic Danes. No single transmission event could be confirmed, but the pairwise nucleotide identity within the patients of Danish origin was relatively high (∼95%), suggesting a recent introduction into Denmark. (2) The 21 patients infected with subtype 4a all came from Northern Africa, Egypt, Pakistan, or the Middle East. (3) Patients from Southern Africa dominated among patients infected with subtype 4r (10 of 12 patients). This study demonstrates that HCV genotype 4d has been introduced in and spread among Danish intravenous drug users. The remaining subtypes show restricted distribution, infecting almost exclusively patients from geographical areas with a relatively high prevalence of HCV genotype 4 infections.

An overview about hepatitis C: a devastating virus

Hepatitis C (HCV) is the disease that has affected around 200 million people globally. HCV is a life threatening human pathogen, not only because of its high prevalence and worldwide burden but also because of the potentially serious complications of persistent HCV infection. Chronicity of the disease leads to cirrhosis, hepatocellular carcinoma and end-stage liver disease. HCV positive hepatocytes vary between less than 5% and up to 100%, indicating the high rate of replication of viral RNA. HCV has a very high mutational rate that enables it to escape the immune system. Viral diversity has two levels; the genotypes and Quasiaspecies. Major HCV genotypes constitute genotype 1, 2, 3, 4, 5 and 6 while more than 50 subtypes are known. All HCV genotypes have their particular patterns of geographical distribution and a slight drift in viral population has been observed in some parts of the globe.

The neglected hepatitis C virus genotypes 4, 5 and 6: an international consensus report

Abstract Hepatitis C virus (HCV) genotypes 4, 5 and 6 represent >20% of all HCV cases worldwide. HCV-4 is mainly seen in Egypt, where it represents 90% of all HCV cases. Antischistosomal therapy was the main cause of contamination there, followed by procedures performed by informal providers and traditional healers such as dental care, wound treatment, circumcision, deliveries, excision and scarification. It is also highly prevalent in sub-Saharan Africa and in the Middle East. In Europe, its prevalence has recently increased particularly among intravenous drug users and in immigrants. HCV-5 is mainly found in South Africa, where it represents 40% of all HCV genotypes, but four pockets of HCV-5 were found in France, Spain, Syria and Belgium and sporadic cases were found elsewhere. The mode of transmission is mainly iatrogenic and transfusion. HCV-6 is found in Hong Kong, Vietnam, Thailand and Myanmar and also in American and Australian from Asian origin. The response to treatment in HCV-4 is intermediate between HCV-1 and HCV-2 and HCV-3. A sustained viral response is achieved in 43-70% with pegylated interferon and ribavirin. It is higher in Egyptians than Europeans and Africans and is negatively related to insulin resistance and to the severity of fibrosis. It increases to >80% with 24 weeks of therapy only if a rapid virological response is achieved. In HCV-5, a sustained virological response is achieved in >60% with 48 weeks of therapy. HCV-6 is also considered an easy-to-treat genotype, leading to a response in 60-85% of cases.

Emergence of hepatitis C virus genotype 4: phylogenetic analysis reveals three distinct epidemiological profiles

Hepatitis C virus (HCV) genotype 4 (HCV-4) infection is considered to be difficult to treat and has become increasingly prevalent in European countries, including The Netherlands. Using a molecular epidemiological approach, the present study investigates the genetic diversity and evolutionary origin of HCV-4 in Amsterdam, The Netherlands. Phylogenetic analysis of the NS5B sequences (668 bp) obtained from 133 patients newly diagnosed with HCV-4 infection over the period from 1999 to 2008 revealed eight distinct HCV-4 subtypes; the majority of HCV-4 isolates were of subtypes 4d (57%) and 4a (37%). Three distinct monophyletic clusters were identified, with each one having a specific epidemiological profile: (i) Egyptian immigrants infected with HCV-4a (n = 46), (ii) Dutch patients with a history of injecting drug use infected with HCV-4d (n = 44), and (iii) Dutch human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) infected with HCV-4d (n = 26). Subsequent molecular clock analyses confirmed that the emergence of HCV-4 within these three risk groups coincided with (i) the parenteral antischistosomal therapy campaigns in Egypt (1920 to 1960), (ii) the popularity of injecting drug use in The Netherlands (1960 to 1990), and (iii) the rise in high-risk sexual behavior among MSM after the introduction of highly active antiretroviral therapy (1996 onwards). Our data show that in addition to the influx of HCV-4 strains from countries where HCV-4 is endemic, the local spread of HCV-4d affecting injecting drug users and, in recent years, especially HIV-positive MSM will further increase the relative proportion of HCV-4-infected patients in The Netherlands. HCV-4-specific agents are drastically needed to improve treatment response rates and decrease the future burden of HCV-4-related disease.

Hepatitis C virus genotypes in 1,504 patients in Slovenia, 1993-2007

In order to identify the main routes of hepatitis C (HCV) transmission and to determine the HCV genotype distribution and its dynamics during a 15-year period in Slovenia, HCV genotypes were detected using the INNO-LiPA HCV II (Innogenetics) test for serum samples obtained from 1,504 patients representing 72.6% of all patients with chronic hepatitis C diagnosed from 1993 to 2007. HCV genotype 1 was predominant (56%), followed by genotypes 3, 2, and 4, with a prevalence of 37.8%, 5%, and 1.2%, respectively. HCV genotypes 5 and 6 were not detected in any patient. Patients infected with HCV genotype 3 were significantly younger (mean age 28.9 +/- 8.5 years) than those infected with genotype 1 (mean age 38.9 +/- 14.8 years; P < 0.0001) and those infected with HCV genotype 2 (mean age 50.3 +/- 18.2 years; P < 0.0001). Intravenous drug use was identified as the most frequent possible HCV transmission route (34.3%), followed by medical-related transmission such as transfusion of HCV-contaminated blood or blood products, and hemodialysis (12.5%). Being an intravenous drug user was found to be strongly associated with HCV genotype 3 (OR, 3.71 [95% CI, 2.97-4.65]; P < 0.0001) and reporting infection by transfusion of blood or blood products was found to be strongly associated with HCV genotype 1 (OR, 3.28 [95% CI, 2.18-4.95]; P < 0.0001). During the 15-year period, the proportion of genotype 3 increased substantially, reflecting the fact that the HCV epidemic in Slovenia is driven mostly by intravenous drug use.

[Chronic hepatitis C virus infection and associated liver disease among the inmates of a Spanish prison]

OBJECTIVE

The objective of this study was to determine the prevalence and genotype distribution of chronic hepatitis C virus (HCV) infection in a penitentiary population. The secondary objective was to describe histological findings in liver of the biopsied population, and identify risk factors associated with liver fibrosis and inflammatory activity.

METHODS

Among 800 inmates, 730 accepted HCV antibody screening and PCR confirmation. Sociodemographic, behavioral, and incarceration-related variables were analyzed. Liver biopsy was offered to individuals with chronic HCV infection. Advanced liver disease was defined as fibrosis 3 and/or an inflammatory activity index score 8).

RESULTS

HCV antibodies were found in 279 inmates. PCR confirmed HCV infection in 250 inmates, yielding a prevalence of 34.2% (95% confidence interval [CI]: 30.8-37.8). Intravenous drug use was independently associated with HCV infection, odds ratio (OR) 51.7 (95% CI: 31-86). Genotypes were 1a 32.9%, 3 29.7%, 1b 18.4% and 4 17.1%. Fifty-one liver biopsies were performed; advanced liver disease was found in 7 patients (13.7%) based on fibrosis and in 31 patients (60.7%) based on the inflammatory activity index. High AST and ALT levels were associated with advanced liver disease established on both fibrosis and inflammatory activity (P<.05). Lengthy intravenous drug use was associated with inflammatory activity (P=.02; OR 1.2; 95% CI: 1.03-1.7).

CONCLUSIONS

Persistent HCV infection is highly prevalent among prison inmates and is associated with intravenous drug abuse. HCV genotype diversity is higher in prison inmates than in the general population. Higher transaminase levels are associated with advanced liver disease.

Response to pegylated interferon plus ribavirin in HIV-infected patients with chronic hepatitis C due to genotype 4

Hepatitis C virus (HCV) genotypes 1 and 4 respond less well to pegylated interferon (pegIFN) plus ribavirin (RBV) therapy. For this reason most studies merge these two genotypes when assessing virological response. However, in most trials the HCV genotype 4 population is rather small, and conclusions are mainly derived from what occurs in HCV-1 patients. All HCV-4 patients coinfected with HIV who received pegIFN plus RBV in two different multicentre studies, PRESCO and ROMANCE, conducted respectively in Spain and Italy, were retrospectively analyzed. Baseline plasma HCV-RNA, proportion of patients with HCV-RNA <10 IU / mL at week 4 (rapid virological response), and HCV-RNA declines >2 logs at week 12 (early virological response, EVR) were all assessed as predictors of sustained virological response (SVR). Overall, 75 patients (60 men) were evaluated. Median age was 40 years and median CD4 count 598 cells / mm(3); 49% had plasma HIV-RNA <50 copies / mL; 71% had elevated liver enzymes and 31% had advanced liver fibrosis (Metavir F3-F4). Median serum HCV-RNA was 5.7 log IU / mL. Rapid virological response was attained by 10 (20%) patients and EVR by 26 (42%). Using intention-to-treat and on-treatment (OT) analyses, SVR was achieved by 21 / 75 (28%) and 21 / 62 (34%) of HCV-4 patients, respectively. In the multivariate analysis (OT), baseline HCV-RNA (OR 0.09 for every log increment; 95% CI: 0.01-0.7) and EVR (OR: 7.08; 95% CI: 1.8-27.2) were significantly and independently associated with SVR. This is the largest series of HIV-infected patients with chronic hepatitis C due to HCV-4 treated with pegIFN plus RBV examined so far and the results show that HCV-4 behaves similarly to HCV-1. Therefore, these patients should be considered as difficult to treat population. Baseline serum HCV-RNA and EVR are the best predictors of SVR in HCV-4 / HIV-coinfected patients.

Very Early Viral Kinetics on Interferon Treatment in Chronic Hepatitis C virus Genotype 4 Infection

Background

Interferon (IFN)-resistant hepatitis C virus strains limit efficacy of antiviral combination therapy in patients infected with genotypes 1 and 4. A single test dose of IFN was useful to identify non-responders to IFN-α2b/ribavirin (RBV) or likely non-responders to pegylated (PEG)-IFN-α2a/RBV therapy in genotype 1 patients. Our aim was to investigate this approach in genotype 4 patients.

Methods

Viral load was measured in 46 patients before and 24 h after 10 megaunits (MU) IFN-α2b, and before and during 2 weeks of daily 5 MU IFN-α2b administration. Thereafter, patients received 48 weeks combination therapy with either 180 μg PEG-IFN-α2a/week ( n=33), 1.5 μg/kg PEG-IFN-α2b/week ( n=7) or 5 MU IFN-α2b/2 days ( n=6), along with 1–1.2g RBV/day. For prediction analysis the largest group (PEG-IFN-α2a) was evaluated only.

Results

Median 24 h log10 change after 10 MU IFN-α2b was 1.15 (range 0.08–2.48) and after 5 MU IFN-α2b was 0.81 (-0.12–2.22; P<0.0001). Log10 changes after 2 weeks on 5 MU IFN-α2b daily and 24 h after 10 MU were the best predictors of early virological response (defined by negativity of a standard qualitative PCR) to PEG-IFN-α2a/RBV combination therapy (area under curve [AUC]=0.97; P<0.001, receiver operating characteristics), 24 h log10 change after 10 MU was the best predictor of sustained virological response (SVR; AUC=0.91, P=0.001).

Conclusion

As in genotype 1 patients, there is large variation in IFN responsiveness, including the presence of resistant strains, in genotype 4 patients. A 24 h log10 change after 10 MU IFN-α2b is an excellent predictor of SVR on PEG-IFNα2a/RBV combination therapy. This test may be useful to obtain homogeneous groups for clinical studies and could help in clinical decision making.

The changing epidemiology of hepatitis C virus infection in Europe

The epidemic of hepatitis C virus (HCV) infection in Europe is continuously evolving and epidemiological parameters (prevalence, incidence, disease transmission patterns and genotype distribution) have changed substantially during the last 15 years. Four main factors contribute to such changes: increased blood transfusion safety, improvement of healthcare conditions, continuous expansion of intravenous drug use and immigration to Europe from endemic areas. As a result, intravenous drug use has become the main risk factor for HCV transmission, prevalent infections have increased and genotype distribution has changed and diversified. Hence, prevalence data from studies conducted a decade ago may not be useful to estimate the current and future burden of HCV infection and additional epidemiological studies should be conducted, as well as new preventive strategies implemented to control the silent epidemic. This review summarizes recently published data on the epidemiology of HCV infection in Europe focusing on the factors currently shaping the epidemic.

Improving outcome in patients with hepatitis C virus genotype 4

Several factors influence treatment outcomes among patients with chronic hepatitis C. A trend is growing to adapt an individualized treatment approach to optimize treatment outcomes among chronic hepatitis C patients. Hepatitis C virus (HCV) genotype is an important factor that determines treatment outcomes among patients with chronic hepatitis C. HCV has six genotypes, and genotype 4 (G4) accounts for 20% of all global HCV infections. Patients with G4 are underrepresented in clinical trials involving patients with chronic hepatitis C because most patients infected with G4 are in Egypt, Africa, and Middle Eastern countries. Therefore, there is little information about the predictors of response to standard treatment among chronic hepatitis C patients with HCV G4. Initial evidence suggested that patients with G4 HCV are as difficult to treat as patients with G1; however, recent evidence suggests that the response rates to treatment among patients with G4 may be better than those with G1 but not those with G2 or G3. This review discusses the clinical data among patients with G4 and assesses the impact of an individualized approach on improved treatment outcomes in these patients.

Clinical and pathological characteristics and response to combination therapy of genotype 4 chronic hepatitis C patients: experience from a spanish center

This observational study evaluated the characteristics of genotype 4 chronic hepatitis C (CHC) patients and their response to combination therapy in Spain. 383 patients with CHC, 44 with genotype 4-HCV infection, were investigated. Nineteen genotype 4-HCV infected patients received IFNalpha-2b (3 MU three times weekly) plus ribavirin (1-1.2 g/day) and ten received Peg-IFNalpha-2b (1.5 microg/kg/week) plus ribavirin (1-1.2 g/day) for 12 months. A sustained virological response (SVR) was evaluated. Genotype 4-HCV was detected in 11.5% of patients, and was significantly associated with a higher proportion of infection through intravenous drug use (46% vs 11%; p<0.001), a higher alcohol intake (35% vs. 7%; p<0.001), higher proportion of anti-HBc positivity (41% vs. 22%; p<0.05), lower ALT (87+/-50 vs. 139+/-142 IU/L; p<0.001) and AST (53+/-30 vs. 85+/-126 IU/L; p<0.001) levels, lower viremia (4.1 +/- 7.7 (x 10(5)) vs . 7.3 +/- 9.8 IU(x 10(5) )/mL) p<0.05) and less fibrosis (stage 3-4 in 21% vs. 32%; p<0.06). Sixteen (55%) out of the 29 patients treated with combination therapy achieved a sustained virological response (SVR) while 10 (36%) were non-responders and 3 (9% relapsed. In conclusion, the lower stage of fibrosis, lower viremia and higher SVR rate than genotype 1 suggest a less aggressive pattern of diseased caused by this genotype.

Characterization of full-length hepatitis C virus genotype 4 sequences

Over 85% of the world's nearly 170 million hepatitis C virus (HCV)-infected subjects exist in regions of Africa, Southeast Asia and Middle Eastern countries where genotypes 4-6 are very common. In particular, HCV genotype 4 is highly prevalent in Egypt with more than 19% of the population infected and chronic HCV representing one of the top five leading causes of death, due in part to ineffective interferon alpha treatment against this genotype. Despite this, very little work has been carried out to characterize the sequence diversity of genotype 4, which will be critical to the development of effective vaccines and antiviral therapies against this genotype. As a result of the paucity of sequence data available for HCV genotype 4, for which only one full genome sequence is currently available, we were interested in characterizing additional genotype 4 sequences and to provide reagents for amplification of this genotype. Here we describe seven unique HCV genotype 4a full genomes, in addition to a single genotype 4d genome, and characterize their sequence diversity in relation to other more closely characterized HCV genotypes.

Tratamiento de las hepatitis víricas (II). Tratamiento de la hepatitis crónica C

Hepatitis C virus infection is the principal cause of chronic liver disease, cirrhosis and hepatocellular carcinoma in the Western World. Chronic hepatitis C is often silent, most of the times discovered only by routine serologic or biochemical testing and the interval between infection and the development of cirrhosis exceed 30 years. Interestingly the complications of chronic hepatitis C virus infection can be prevented by antiviral therapy. At present, the combination of pegylated interferon-alfa and ribavirina has become the standard treatment of chronic hepatitis C. The management of HCV infection in "special populations" (HIV coinfection and HCV therapy-experienced patient) has improved significantly over the past few years, through a better knowledge of the disease and the publication of several clinical trials performed in these patients. At presents, a number of new anti-HCV therapies are in development. Future drugs for HCV infection might make possible to eradicate HCV in future.

HCV genotype 4 in Belgium: three distinct patterns among patients from European and African origin

BACKGROUND

Considered uncommon in western countries some years ago, hepatitis C virus of genotype 4 is now spreading in some areas of Europe. This is assumed to be due to immigration from a region of high prevalence for this genotype and to propagation among drug users. In the south of Belgium, genotype 4 currently accounts for 10% of hepatitis C virus patients and its prevalence is increasing with time.

OBJECTIVE

To better define the genotype 4 carriers' characteristics.

METHODS

In a database comprising 1726 viraemic hepatitis C virus patients, the files of 85 genotype 4 carriers were reviewed.

RESULTS

Beside the African (58%) and European drug user (15%) subgroups classically described, a third subgroup consisting of European nondrug users (26%) was identified as peculiar: these patients were older, had been mostly contaminated sporadically, presented a great diversity of subtypes, and were mainly of Italian origin. In this subgroup, contamination was supposed to be ancient, having occurred probably in Italy before immigration into Belgium. By contrast, European drug users were infected with only two subtypes (4c/4d and 4), an observation in favour of recent spread. Africans had a great diversity of subtypes, were young, and were mostly contaminated sporadically in their home countries. Despite their epidemiological differences, the clinical management, and in particular the rates of eligibility for treatment, were similar for these three groups.

CONCLUSIONS

Three different patterns of genotype 4 carriers were observed, corresponding to three different spreading profiles. They did not induce, however, different clinical management.

Changes in the distribution of hepatitis C virus (HCV) genotypes over time in Spain according to HIV serostatus: implications for HCV therapy in HCV/HIV-coinfected patients

BACKGROUND

Changes in the prevalence of distinct hepatitis C virus (HCV) genotypes and subtypes over time have not been explored in detail.

METHODS

A retrospective analysis was carried out in all specimens from subjects with chronic hepatitis C sent for testing to a reference laboratory in Spain since 1998-2004.

RESULTS

A total of 1226 distinct subjects were analyzed. The most frequent HCV genotype was 1 (64.1%), followed by 3 (20.9%) and 4 (11.7%). The most frequent HCV subtype was 1b (32.4%). A total of 797 patients (65%) were HIV-positive. Although genotype 1 was the most frequent, it represented 74.6% of HIV-negative and 58.5% of HIV-positive patients (p<0.01). While HCV subtype 1a was the most frequent among HIV-positive subjects (32.1%), 1b was the most common in HIV-negative patients (53.8%). There was a significant increase in the prevalence of genotype 4 and conversely a decline in genotype 3 among HIV-positive patients over time.

CONCLUSION

Genotype 1 is the most frequent HCV variant circulating in Spain. Genotypes 3 and 4 are significantly more prevalent in HIV/HCV-coinfected than in HCV-monoinfected patients. However, HCV-3 has declined and HCV-4 is increasing in the former group. These findings are relevant given their different susceptibility to interferon-based therapies.

Distribution of hepatitis C virus genotypes in the Middle East

It is well established that hepatitis C develops into cirrhosis of the liver and hepatocellular carcinoma (HCC) both of which are fatal diseases. The World Health Organization estimates that there are at least 21.3 million hepatitis C virus (HCV) carriers in the Eastern Mediterranean countries, which is close to the number of carriers estimated in the Americas and Europe combined. With such a high disease burden of HCV infection in this part of the world, and in light of the new evidence that genotypes may influence the outcome of antiviral therapy, the focus of this review is on the epidemiology and distribution of HCV genotypes in the Eastern Mediterranean countries. Accumulated data show that there are two main patterns for the distribution of HCV genotypes in the Middle East: in the first pattern, genotype 4 is prevalent in most of the Arab countries, and in the second pattern, genotype 1a or 1b predominates in the non-Arab countries. Results from the limited number of clinical trials on the treatment of chronic HCV genotype 4 using peginterferon alfa-2b in combination with ribavirin are encouraging. However, efforts to develop more effective antiviral therapies and the establishment of an effective HCV vaccine remain the largest challenges for the near future.

Genetic diversity of HCV genotype 2 strains in South Western France

Hepatitis C virus (HCV) is a major cause of chronic hepatitis and liver disease worldwide. The genetic heterogeneity of HCV and its spread among infected patients can be examined accurately by nucleotide sequencing. The diversity of HCV genotype 2 strains (HCV-2) was studied in a large cohort of patients in the Midi Pyrénées area of southern France. Phylogenetic analysis was performed on 344 NS5B sequences from patients infected with HCV-2. These included 145 strains whose E2 region was also analyzed, and epidemiological data were collected for the corresponding patients. HCV-2 accounts for 11.3% of HCV infections in this area. Phylogenetic analysis of NS5B sequences revealed eight subtypes, while that of the E2 region provided congruent results for 100% of strains. The most frequent subtypes were 2i (24.7%), 2k (22.4%) 2c (17.4%), and 2a (10.8%). The mean age of HCV-2-infected patients was 55.5 years. Epidemiological data showed that blood transfusion is the major route of infection, but it was not associated with any particular subtype. By contrast, intravenous drug users were infected predominantly with genotype 2a. HCV-2a-infected patients were younger than patients infected with other subtypes (48 vs. 56.5 years, P < 0.01). This study shows substantial genetic diversity of HCV-2 subtypes in the south of France and the spread of 2a strains via intravenous drug users.

High prevalence of hepatitis C virus subtypes 4c and 4d in Malaga (Spain): Phylogenetic and epidemiological analyses

Hepatitis C virus (HCV) is a major aetiological agent of chronic hepatitis and it may lead to the development of liver cirrhosis and hepatocellular carcinoma. HCV has been classified into six clades as a result of high genetic variability. A commercial procedure to genotype HCV in 678 patients from Carlos Haya Regional University Hospital, Malaga was used to study the distribution of HCV genotypes in Malaga, southern Spain. A high prevalence of HCV-4 (10.2%) was found. This genotype is found more commonly in Egypt, Central Africa and the Middle East. The distribution of the different subtypes in the 69 patients with HCV-4 was as follows: 4.3% subtype 4e, 7.2% subtype 4a, 11.5% not subtypable, and 76.8% subtype 4c/4d. Of the 53 4c/4d patients, 69% were intravenous drug users and 31% non-intravenous drug users. In order to characterise further the HCV-4c/4d patients, sequences of the non-structural 5B gene (393 bp) were obtained from 36 HCV-4c/4d-infected untreated patients. Phylogenetic tree topologies distinguished clearly the two subtypes: 11 patients were infected by subtype 4c and 25 by 4d. This phylogenetic analysis, reinforced by the epidemiological characteristics, suggests the extension of the HCV-4c and -4d subtypes in the area of Malaga among both intravenous drug users and non-intravenous drug users.

Follow-up of the prevalence of hepatitis C virus genotypes in Spain during a nine-year period (1996-2004)

BACKGROUND

Recent data suggest that the prevalence of genotype 4 HCV strains among Spanish carriers is increasing.

OBJECTIVE

To assess changes in the prevalence of HCV genotypes in Spain during the last nine years.

METHODS

HCV RNA was amplified by the polymerase chain reaction from 3161 serum samples from unselected, anti-HCV-positive individuals, and the HCV genotype was identified by a reverse hybridisation assay (line probe assay, LiPA). Samples came from 17 different regions of Spain and were obtained between January, 1996 and December, 2004.

RESULTS

The overall prevalence of HCV genotypes was: 1b, 41.3%; 1a, 24.1%; 3, 19.6%; 4, 11.6%; 2, 3.1%; and 5, 0.3%. The prevalence of genotypes 1a, 3 and 4 increased significantly among patients born after 1950, and that of genotype 1b decreased among them. These significant differences in regard to age were also observed among patients lacking notified high-risk factors. A main switch-up in prevalence of genotypes 1a and 3 was found when patients born in 1941-1950 were compared with those born in 1951-1960, but the same finding in genotype 4 was delayed to patients born in 1961-1970.

CONCLUSIONS

Two separate epidemics of HCV seem to have occurred in Spain during the last 30 years. The former one involved the spread of HCV genotypes 1a and 3. The second was more recent, and involved the spread of genotype 4.

Chronic hepatitis C: genotypes 4 to 9

Infection with hepatitis C virus (HCV) genotypes 1, 2, or 3 is widely distributed throughout the world and has been the focus of the majority of studies on the epidemiology and treatment of chronic hepatitis C. Infection with HCV genotypes 4 through 9 is prevalent in some geographic areas where the disease burden of chronic hepatitis C approaches endemic levels (eg, HCV genotype 4 in Egypt where there is an HCV infection prevalence of approximately 18%). This article reviews the existing literature, which suggests that chronic hepatitis C with genotypes 4 through 9 may exhibit epidemiologic, clinical, and treatment outcome differences from infection with genotypes 1, 2, or 3.

Heterogeneity of hepatitis C virus genotype 4 strains circulating in south-western France

Hepatitis C virus (HCV) is a major cause of liver disease. Knowledge of HCV variability is crucial for clinical and epidemiological analysis. HCV genotype 4 (HCV-4) has become increasingly prevalent in European countries, including France, in recent years. The present study investigates the heterogeneity of HCV-4 in south-western France by phylogenetic analysis of NS5B sequences from 166 patients. The E2 region of 90 strains was also analysed. Genotype 4 accounts for 7·4 % of HCV infections in this area. Analysis of the NS5B region revealed 12 subtypes and the NS5B and E2 phylogeny data were congruent, except for one strain. The epidemiological data indicated two main groups of patients. One included intravenous drug users (IVDUs) of French origin, who were infected by homogeneous strains of subtypes 4a or 4d. The second group comprised non-IVDU patients who were infected with heterogeneous strains. This group was subdivided into patients of French origin, who were infected with eight subtypes, and patients from non-European countries (Central Africa or the Middle East), who were mainly infected with 4f, 4k, 4r and other subtypes; they showed the greatest genetic heterogeneity. This study of a large cohort of patients shows the great diversity of HCV-4 strains, and that these subtypes have spread differently.

Management of hepatitis C virus genotype 4

Hepatitis C virus (HCV) genotype 4 is predominantly found in the Middle East and North Africa. Because most of the large randomized controlled trials of antiviral therapy for chronic hepatitis C were conducted in North America and Europe, little is known about management of patients with this particular genotype. Based on the available data, sustained virological response rates to interferon-based therapies appear to be intermediate between the relatively resistant HCV genotype 1 and the readily responsive genotypes 2 and 3. Several large prospective studies of pegylated interferon plus ribavirin combination therapy, the current gold-standard treatment, have recently been completed and will be reviewed.

High prevalence of hepatitis C virus type 5 in central France evidenced by a prospective study from 1996 to 2002

From 1996 to 2002, hepatitis C virus (HCV) typing was prospectively performed for 1,281 unselected HCV-infected and viremic patients, irrespective of their clinical status. Eighty-three patients (6.5%) were coinfected with human immunodeficiency virus (HIV) and HCV. A total of 1,195 strains were identified by a serotype screening (Murex HCV Serotyping 1-6 assay) and/or genotyping (Inno-LiPA HCV II) test. The distribution of HCV types showed an unusually high rate of type 5 (14.2%) that was stable over time and was the third most frequent type, after type 1 (59.1%) and type 3 (15.1%). HCV type 5 was more frequent in patients who were older than 50 (P = 10(-6)), but its frequency did not differ significantly by gender (P = 0.21). Serotyping was performed for 1,160 strains but failed for 30.2% of them. The efficiency depended on HIV status (for HCV-HIV-coinfected patients, half of the strains were untypeable) and HCV type. Genotyping was performed for 428 samples, with an overall efficiency of 99.3%. It failed in three cases, which were subsequently identified as HCV type 2. Serotyping and genotyping results for 39 patients showed discrepancies between the two methods for 4 patients, who had HCV type 2, type 6, or mixed infections. Thus, HCV type 5 may also be encountered frequently in Western countries. Its apparent confinement to a restricted area raises the question of how it emerged and underscores the need for further studies of HCV type prevalence, routes of transmission, pathogenicity, and responses to treatment.

High prevalence of hepatitis C virus type 5 in central France evidenced by a prospective study from 1996 to 2002

From 1996 to 2002, hepatitis C virus (HCV) typing was prospectively performed for 1,281 unselected HCV-infected and viremic patients, irrespective of their clinical status. Eighty-three patients (6.5%) were coinfected with human immunodeficiency virus (HIV) and HCV. A total of 1,195 strains were identified by a serotype screening (Murex HCV Serotyping 1-6 assay) and/or genotyping (Inno-LiPA HCV II) test. The distribution of HCV types showed an unusually high rate of type 5 (14.2%) that was stable over time and was the third most frequent type, after type 1 (59.1%) and type 3 (15.1%). HCV type 5 was more frequent in patients who were older than 50 (P = 10(-6)), but its frequency did not differ significantly by gender (P = 0.21). Serotyping was performed for 1,160 strains but failed for 30.2% of them. The efficiency depended on HIV status (for HCV-HIV-coinfected patients, half of the strains were untypeable) and HCV type. Genotyping was performed for 428 samples, with an overall efficiency of 99.3%. It failed in three cases, which were subsequently identified as HCV type 2. Serotyping and genotyping results for 39 patients showed discrepancies between the two methods for 4 patients, who had HCV type 2, type 6, or mixed infections. Thus, HCV type 5 may also be encountered frequently in Western countries. Its apparent confinement to a restricted area raises the question of how it emerged and underscores the need for further studies of HCV type prevalence, routes of transmission, pathogenicity, and responses to treatment.

Infection with hepatitis C virus genotype 4 in the United States

BACKGROUND

Hepatitis C virus genotype differences seem to be of considerable clinical significance because they affect responses to antiviral therapy. HCV genotype 4 is rare in the United States and there are few published data regarding response to therapy in patients with HCV genotype 4 infection.

OBJECTIVES

To assess epidemiologic factors associated with HCV genotype 4 infection in United States and to describe the response rate to therapy with the combination of alpha interferon and ribavirin.

METHODS

All hepatologists in our Division were asked for information about patients they had treated with HCV genotype 4. In addition, we searched the computer database from Saint Louis University Hospital in the last 40 months (1999 to 2002). Twenty HCV genotype 4 patients were identified. A retrospective chart review was performed to collect information about their demographics, risk factors for acquisition of infection, baseline laboratory studies and response to antiviral therapy.

RESULTS

A risk factor for exposure to HCV was noted in 14 cases (70%); 12 patients had a history of illicit drug use, whereas a history of blood transfusion was detected in three cases; 1 patient had both risk factors. Only 4 of 20 individuals had fibrosis stage 3 or 4 on liver biopsy. Seventeen patients were treated, 14 of whom completed therapy; 10 patients were sustained responders.

CONCLUSIONS

As with other HCV genotypes, most patients with HCV genotype 4 in the United States acquire the infection through intravenous drug use, liver disease is often mild to moderate in severity and 59% of our patients had a sustained virologic response after combination therapy with interferon and ribavirin.

Genomic and phylogenetic analysis of hepatitis C virus isolates: a survey of 535 strains circulating in southern France

The present study examines the distribution of Hepatitis C virus (HCV) genotypes in Marseille, France in 2001-2002 and evaluates the efficiency of two in house direct sequence PCR protocols based on 5'NC analysis or NS5B analysis. By 5'NC sequencing, the distribution of 535 HCV strains derived from patients attending gastroenterology and AIDS referral centers, or dialysis units was as follows: 33% were infected by genotype 1a; 26% by 1b; 7% by 2; 22% by 3a; 10.7% by 4. In univariate analysis, HCV distribution was associated with age and source of infection, whereas in multivariate analysis only injecting drug use was an independent determinant for genotype distribution. Among the 535 specimens submitted to 5'NC direct sequencing, 18% could not be classified accurately into subtypes. A subset of 187 samples was amplified efficiently and sequenced by targeting the NS5B region of the viral genome. The two methods yielded concordant results in 70% of cases. Specimens unsubtypeable or misclassified most frequently by 5'NC analysis were type 1b and subtypes 2a/2c and 4a/4c. The data show that 5'NC direct sequence analysis is a sensitive method to identify genotypes in all cases, but that it can lead to subtyping misclassification (in particular, subtype 1b and 1a) or doubtful results (in particular subtypes 2a/2c and 4a/4c). Conversely, NS5B direct sequence assay, based on phylogenetic analysis, allowed better discrimination between subtypes. These two approaches are complementary and should be made available in clinical laboratories to ensure a reliable survey of HCV strains.

[Genetic variability of hepatitis C virus in the health area of Elche (Spain). Correlation between core antigen and viral load]

We investigated the prevalence of the various genotypes of hepatitis C virus (HCV) in 281 patients evaluated between March, 2000 and March, 2002 in the health area of Elche. Of these patients, 55 were coinfected with human immunodeficiency virus (HIV). The genotype was related to viral load and the co-existence of HIV infection. Likewise, the relationship between these parameters and the presence of the HCV core antigen was established. The results indicate that genotype 1b was the most prevalent (38.4%) followed by genotype 3a (23.1%). Patients coinfected with HIV presented fewer infections due to group 1 genotypes (p < 0.05).Patients with HIV presented a greater viral load in all the genotypes, with genotype 3 presenting a high viral load. Detection of the HCV core antigen showed a close correlation with viral load determinations. Although not yet sufficiently assessed, determination of the HCV core antigen constitutes a simple technique that could eventually contribute to improving the management of patients with chronic HCV hepatitis.

Seroprevalence of hepatitis C markers among intravenous drug users in western European countries: a systematic review

Currently, the most important risk factor for hepatitis C virus (HCV) infection in Europe is intravenous drug use. To establish a better insight into the epidemiology of hepatitis C among intravenous drug users (IVDUs) in western European countries a systematic review on the prevalence of hepatitis C markers and their determinants was performed. Reports were identified by searches on Medline and on the internet and by screening reference lists of selected papers. The prevalence rates of anti-HCV in western European IVDUs reported in the 66 studies selected for analysis, ranged between 37 and 98%. No relation was found between prevalence rates and mean age, mean duration of intravenous drug use, geographical area, setting of the study, method of recruitment or the year(s) of collection of samples. Eleven studies concerning the prevalence of HCV-RNA in hepatitis C-infected IVDUs were selected for analysis. Prevalence rates ranged from 26 to 86%. Based on five studies, a statistically significant positive linear relation was found between the mean age of study population and the prevalence of HCV-RNA. Our analysis revealed considerable variation in prevalence rates of hepatitis C markers among IVDUs in western Europe. We found no conclusive explanation for this variability. Further research investigating the dynamics of the hepatitis C epidemic in IVDUs is necessary.

Changes in the prevalence of hepatitis C virus (HCV) genotype 4 in Calabria, Southern Italy

The aim of this study was to assess changes in the prevalence of hepatitis C virus (HCV) genotypes, focusing on genotype 4, by surveying population of chronic hepatitis C patients within an area of Southern Italy. HCV-RNA was detected in serum using two commercial hepatitis C RNA PCR assays (Amplicor Roche Diagnostic System, and AmpliSensor HCV, Nuclear Laser Medicine). PCR products were analyzed for genotyping using a reverse hybridization of the amplified product by a line probe assay (INNO LIPA, Innogenetics). In our Institution we have previously observed, in a period of 18 months (January 1997-May 1998) an initial increase of the genotype 4 which appeared in 3.3% of HCV patients versus a percentage of 1.3%, during 1996. Later data obtained from 702 HCV-RNA positive patients, collected from June 1998 until December 1999 indicated a 3.7% of genotype 4. This percentage increased until to 4.7% in the most recent period studied (January 2000-February 2001). Drug addiction, blood transfusion and sporadically acquired infections represented the most frequent risk factors. In the Calabria region, genotype 1b, the most prevalent isolate (53.3%) and genotype 2a/2c (26.2%) were associated with older age, confirming our previous study. Genotype 4 was the fifth most prevalent genotype observed, just after 3a and 1a subtypes. Spread of genotype 4 in Calabria region is mostly associated to older age when compared to genotype 3a and 1a, but is statistically associated with a younger group of patients when compared with genotype 1b. In conclusion we demonstrated a fourfold increased prevalence of HCV genotype 4 during the last 5 years.

Phylogenetic characterization of genotype 4 hepatitis C virus isolates from Argentina

Among 114 patients infected with hepatitis C virus, three genotype 4 isolates, unusual in Argentina, were detected by phylogenetic analysis over different genomic regions. The patients were not related. One sample was associated with Egyptian sequences, and the others were associated with a Zairean isolate, a fact which reinforces the idea that they are from independent sources.

Phylogenetic analyses confirm the high prevalence of hepatitis C virus (HCV) type 4 in the Seine-Saint-Denis district (France) and indicate seven different HCV-4 subtypes linked to two different epidemiological patterns

Hepatitis C virus (HCV) has been classified into six clades as a result of high genetic variability. In the Seine-Saint-Denis district of north-east Paris, the prevalence of HCV-4, which usually infects populations from Africa or the Middle East, is twice as high as that recorded for the whole of continental France (10.2 versus 4.5%). Although the pathogenicity of HCV-4 remains unknown, resistance of HCV-4 to therapy appears to be similar to that observed for HCV-1. In order to characterize the epidemiology of HCV-4 in Paris, sequences of the non-structural 5B gene (332 bp) were obtained from 38 HCV-4-infected patients. Extensive phylogenetic analyses indicated seven different HCV-4 subtypes. Moreover, phylogenetic tree topologies clearly distinguished two epidemiological profiles. The first profile (52.6% of patients) reflects the intra-suburban emergence of two distinct HCV-4 subclades occurring mainly among intravenous drug users (65% of patients). The second profile shows six subclades [HCV-4a, -4f, -4h, -4k, -4a(B) and a new sequence] and accounts for patients from Africa (Egypt and sub-Saharan countries) who have unknown risk factors (77.8% of patients) and in whom no recent diffusion of HCV-4 is evident. This study indicates the high diversity of HCV-4 and the extension of HCV-4a and -4d subclades among drug users in FRANCE: