Epidemiological changes in hepatitis C virus genotypes in France: evidence in intravenous drug users

Hepatitis C virus (HCV) genotypes are distributed differently depending on geography and route of infection. We characterized the distribution of genotypes in a large cohort of patients with chronic hepatitis C in the South-east of France and evaluated the relative prevalence according to time of acquisition. One thousand, one hundred-and-eighty-three patients who were anti-HCV-positive were studied. HCV genotype distribution has changed significantly from the 1960s to 2000. The prevalence of genotype 1b decreased from 47% before 1978 to 18.8% in the 1990s while the prevalence of genotype 1a and 3a increased during the same period from 18% and 15.3% to 28.8% and 26.3%, respectively. The logistic regression model showed that genotype 1a was significantly more common in patients infected through intravenous drug injection odds ratio ((OR): 2.08, P  < 0.01) and after 1990 (OR: 1.98, P  < 0.05). Genotype 1b was significantly less frequent in patients infected through intravenous drug injection (OR: 0.17, P  < 0.001) and has decreased since 1978 (OR: 0.27, P  < 0.001). Genotype 3a was independently associated with intravenous drug injection (OR: 6.1, P  < 0.001) and tattooing (OR: 8.01, P  < 0.001) and was more frequent in the 1979–90 period (OR: 2.05 and 1.74, P  < 0.001 and P  < 0.05). Our results show a modification of HCV genotypes distribution over the last four decades due to an increase of intravenous drug use (IVDU) contamination and an evolution of HCV genotypes distribution only in IVDU population characterized by a decrease of genotype 1b, an increase of genotype 3a from 1970 to 1990 and a higher increase of genotype 1a which is currently the predominant genotype in our population.     

Seroprevalence, Viremia and Genotype Distribution of Hepatitis C Virus: A Community-Based Population Study in Northern Italy

Background: Our aim was to define the burden of HCV infection and the related risk factors in a sample of the general population of northern Italy Materials and Methods: This is a survey on the prevalence of hepatitis C virus (HCV) infection carried out in a cohort (861 males and 1,293 females aged 17–67 years) from the general population of northern Italy. Results: The crude HCV seroprevalence rate was 3.3%, higher in females than in males (p < 0.01) and with a clear age-related effect (test for linear trend: p < 0.01). When adjusted for sex and age in relation to the reference population, the prevalence was 3.7% )95% CI: 2.9–4.5%). In the univariate analysis, HCV infection was related to intravenous drug use (IVDU) (p < 0.001); transfusion (p < 0.001); tattooing (p = 0.02); chiropodist/manicure (p < 0.001); number of children (p < 0.01); educational level (p < 0.001). In the multivariate analysis sex, age over 50 years, transfusion, IVDU and tattooing were confirmed as risk factors, while the educational level seems to be a protective factors. Separate multivariate analysis for males and females points out that the age shift, the protective effect of education and the number of children as risk factor were present only in females. HCV viremia was detected in the 71.8% of the seropositive, resulting in an infection rate of 2.4% (95% CI: 1.7–3.0%). Genotype 1b accounted for 64.7% of isolates. Conclusion: In the general population of our area, HCV infection is mesoendemic and current infections are mostly sustained by genotype 1b. Received: November 29, 2000 · Revision accepted: October 7, 2001     

Correlation of Genotypes and Route of Transmission with Histologic Activity and Disease Stage in Chronic Hepatitis C

Our objective was to evaluate the histopathological features of chronic hepatitis C of 64 liver biopsies and to correlate this with the route of transmission of hepatitis C virus, the genotype of HCV, and the patient's age. Moderate chronic hepatitis was the most frequently observed (62.5%). Cirrhosis was observed in 14 patients (21.9%) and was more frequently found among patients over 40 years of age (34.3% vs 6.9%, P = 0.025). The mean histopathological activity index (HAI) was significantly higher in the sporadic (10 ± 3.1) than the posttransfusional (7.5 ± 3.7) and the intravenous drug use (IVDU) groups (6.3 ± 2.8) (P < 0.02). Moreover the sporadic group showed more fibrosis (P < 0.04) than the posttransfusional group. No liver cirrhosis was found in the IVDU group. The overall prevalence of HCV variants was: 54.7% type 1b, 4.6% type 1a, 37.5% type 2c, 1.6% type 2b, 1.6% type 2. The genotype distribution showed no relation to the HAI, hepatitis activity (grade), and fibrosis (stage) of the liver disease. In conclusion, the sporadic route of transmission of HCV was related to a more severe chronic hepatic disease, a finding that could influence future antiviral therapies. The predominance of HCV type 1b in this study reflects the higher frequency of this variant in our area. Our data suggests that the ultimate consequence of HCV chronic infection depends on patient age rather than on HCV genotype.     

Epidemiology of hepatitis C in Croatia in the European context

We analyzed prevalence, risk factors and hepatitis C virus (HCV) genotype distribution in different population groups in Croatia in the context of HCV epidemiology in Europe, with the aim to gather all existing information on HCV infection in Croatia which will be used to advise upon preventive measures. It is estimated that 35000-45000 of the Croatian population is chronically infected with HCV. Like in other European countries, there have been changes in the HCV epidemiology in Croatia over the past few decades. In some risk groups (polytransfused and hemodialysis patients), a significant decrease in the HCV prevalence was observed after the introduction of routine HCV screening of blood/blood products in 1992. Injecting drug users (IDUs) still represent a group with the highest risk for HCV infection with prevalence ranging from 29% to 65%. Compared to the prevalence in the Croatian general population (0.9%), higher prevalence rates were found in prison populations (8.3%-44%), human immunodeficiency virus-infected patients (15%), persons with high-risk sexual behavior (4.6%) and alcohol abusers (2.4%). Low/very low prevalence was reported in children and adolescents (0.3%) as well as in blood donors (0%-0.009%). In addition, distribution of HCV genotypes has changed due to different routes of transmission. In the general population, genotypes 1 and 3 are most widely distributed (60.4%-79.8% and 12.9%-47.9%, respectively). The similar genotype distribution is found in groups with high-risk sexual behavior. Genotype 3 is predominant in Croatian IDUs (60.5%-83.9%) while in the prison population genotypes 3 and 1 are equally distributed (52.4% and 47.6%). Data on HCV prevalence and risk factors for transmission are useful for implementation of preventive measures and HCV screening.     

Hepatitis C virus genotypes in north eastern Algeria: A retrospective study

AIM: To determine the frequency of various hepatitis C virus (HCV) genotypes present in patients from north eastern Algeria. METHODS: This is a retrospective cross-sectional study of 435 HCV infected patients from northeast Algeria, detected in the Sadelaoud laboratory and diagnosed between January 2010 and December 2012. The patients were diagnosed with HCV infection in their local hospitals and referred to be assessed for HCV genotype before the antiviral treatment. Demographic information (sex, age and address), genotype, subtype and viral load were retrieved from the patient medical records. The serum samples were tested by the type-specific genotyping assay.RESULTS: The majority of the patients (82.5%) were from the central part of the examined region (P = 0.002). The mean age of the patients studied was 53.6 ± 11.5 years. HCV genotype 1 was the most frequent (88.7%), followed by genotypes 2 (8.5%), 4 (1.1%), 3 (0.9%) and 5 (0.2%). Genotype 6 was not detected in these patients. Mixed infection across the HCV subtypes was detected in twenty patients (4.6%). The genotype distribution was related to age and region. Genotype 1 was significantly less frequent in the ≥ 60 age group than in the younger age group (OR = 0.2; 95%CI: 0.1-0.5, P < 0.001). Furthermore, genotype 1 was more frequent in the central part of the examined region than elsewhere (P < 0.01). CONCLUSION: The HCV genotype (type 1b was dominant) distribution in Algeria is different from those in other northern countries of Africa.     

Acute Hepatitis B in Western Sweden – Genotypes and Transmission Routes

A retrospective study of acute hepatitis B (AHB) during 1995-1996 in G?teborg, Sweden, was carried out to investigate whether the increasing number of hepatitis B virus (HBV) carriers due to immigration in northwestern Europe has influenced the incidence or genotype heterogenicity. 24 cases of AHB were identified, the probable transmission route of which was intravenous drug use (IVDU) in 11 (46%), heterosexual in six (25%), homosexual in one, hemodialysis in two and unknown in four cases. In no case was the source an immigrant with chronic HBV infection. Genotype D was seen in 12 patients, seven being anti-HCV-positive IVD users, two probably infected heterosexually and three with an unknown source. Genotype A was found in six patients: three IVD users, a sexual partner of an IVD user and two dialysis patients. Genotype B was found in one patient infected during travel to Vietnam, and genotype C in one patient, probably infected sexually from a previously identified chronic carrier. In conclusion, genotype D is the main genotype and IVDU still the major risk factor for AHB in Goteborg, while transmission from immigrants appears to be of minor importance despite the fact that this group comprises over 90% of the young, highly infectious carriers.     

Hepatitis C virus genotypes in a non-cirrhotic Italian population with chronic hepatitis C: correlation with clinical, virological and histological parameters. Results of a prospective multicentre study

To identify correlations between the distribution of hepatitis C virus (HCV) genotypes and demographic, pathological and virological parameters of HCV-infected patients, we prospectively recruited 650 patients with biopsy-proven chronic hepatitis C without histological aspects of cirrhosis; none had been treated with antiviral therapy. Data regarding gender, age, mode of HCV transmission, alanine aminotransferase (ALT) and HCV RNA levels, immunoglobulin M (IgM) anticore values, liver histology and histological activity were obtained from each patient and correlated on multivariate analysis with infecting HCV genotype. Fifty-five per cent of the patients were infected with HCV genotype 1, 20% with HCV genotype 2, 18% with HCV genotype 3 and 7% with HCV genotype 4. Non-transfusional HCV transmission, low ALT levels, IgM anticore reactivity and a low histological grading score were independent variables associated with HCV genotype 1. Older age, female gender, post-transfusional transmission and a high histological grading score were related to HCV genotype 2, whilst younger age, history of current/previous drug abuse, high ALT values, low IgM anticore reactivity and high viraemic levels were associated with HCV genotype 3. History of illicit use of intravenous drugs and low HCV RNA levels were the only independent variables correlated with HCV genotype 4. Genotype 1 remains predominant in Italy but the prevalence of HCV genotypes is changing in relation to age and mode of transmission: Italian patients with HCV genotype 3 are younger and exhibit higher levels of ALT and HCV RNA than patients with other genotypes.     

Risk Factors Associated With Chronic Hepatitis C Virus Infection: Limited Frequency of an Unidentified Source of Transmission

Objective: Risk factors have been studied in patients with acute non-A, non-B hepatitis, and approximately 40–50% have no known risk factor for viral acquisition. A significant undefined source of viral transmission has been suggested. We sought to clearly delineate the risk factors in a population of patients with documented chronic hepatitis C virus (HCV) infection to assess the magnitude of HCV transmission without known risk factors.
Methods: Risk factor profiles were carefully assessed in 301 consecutive patients with chronic HCV infection. Patients were classified by gender and age. Overall risk factor distributions were calculated and comparisons were made between groups to detect differences in mode of HCV acquisition.
Results: One hundred ninety-six men and 105 women were studied; 223 were age ≤ 45 yr and 78 were > 45 yr. Overall, 25% of patients had a history of transfusion and 49% had a history of intravenous drug use (IVDU). Only 12% had no history of risk factor exposure. Men were more likely to have a history of IVDU and less likely to have a history of blood transfusion or sexual exposure/household contact. Younger patients were more likely to have a history of IVDU and older patients were more likely to have a history of blood transfusion and to deny all risk factor exposure. Conclusions: A careful history delineated a potential risk factor for HCV acquisition in 88% of patients with chronic HCV infection. Men and younger patients had different risk factor profiles than women and older patients, respectively. It is likely that an important unknown mode of HCV transmission occurs in a significant minority of patients.     

Chronic hepatitis C in Sweden: genotype distribution over time in different epidemiological settings.

Hepatitis C virus (HCV) strains are divided into 6 genotypes and several subtypes. Recent studies reported a change in the relative frequency of genotypes within certain regions. We studied the HCV genotype in 312 Swedish patients with chronic hepatitis C, using a core region primer-specific PCR, and grouped the patients according to parenteral risk factors. The date of infection could be estimated in 127 cases. Genotypes 1a (35%) and 3 (31%) were the most common genotypes, followed by genotype 2 (17%), while only 6% had genotype 1b. Genotype 3 was relatively more frequent among subjects infected sexually or by intravenous drug use. The genotype distribution was different from that in studies from other parts of the world, with a lower frequency of genotype 1 (especially 1b) and a higher frequency of genotype 3. The frequency of genotype 1b has decreased and genotype 3 increased over time. The reasons for a different distribution of genotypes in Sweden, compared with other countries, might be a relatively recent introduction of HCV into the population, or a different pattern of transmission.     

Replacement of hepatitis C virus genotype 1b by genotype 2 over a 10-year period in Venezuela

BACKGROUND: Changes in hepatitis C virus (HCV) genotype distribution with time have been reported in several countries. GOALS: To explore eventual changes in HCV genotype distribution in Venezuela over a 10 years period. STUDY: HCV genotype was determined by direct sequencing of the 5' noncoding region, in 236 isolates circulating in patients treated during years 2005 to 2006. Genotype distribution was compared with the one observed in 43 patients followed during years 1994 to 1996. RESULTS: The prevalence HCV genotype 1 and 2 was 70% and 26%, respectively, in patients followed during years 1994 to 1996. The frequency of genotype 2 was significantly increased to 41% (P=0.04) in patients treated during years 2005 to 2006. A significant reduction in HCV genotype 1b prevalence (48% to 27%, P=0.01) was also observed after this 10 years period, whereas the prevalence of HCV genotype 1a did not change over time (22% vs. 27%, NS). Transfusion was more significantly associated with infection with HCV genotype 1b than with other genotypes (52% vs. 20%, P=0.002). CONCLUSIONS: HCV subtype 1b seems to have been displaced by HCV genotype 2 in a relatively short period, without increase in the frequency of genotype 3. The low frequency of HCV genotype 3 in Venezuela might be due to the fact that intravenous drug use in Venezuela is less common than in other countries. The implementation of anti-HCV testing in blood banks since 1994 in Venezuela, might have contributed to the reduction in the frequency HCV genotype 1b infection.     

Interleukin-10 - 1082 GG polymorphism influences the occurrence and the clinical characteristics of hepatitis C virus infection

BACKGROUND/AIMS: In this study, we determined the genotypic and allelic frequencies of the Interleukin (IL)-10(-1082G/A) IL-10(-592A/C), and IL-10(-819C/T) polymorphisms, and their association with the risk to develop B cell Non Hodgkin Lymphoma (NHL) in hepatitis virus C (HCV) carriers. RESULTS: Genetic polymorphisms in the IL-10 gene promoter were studied in 250 consecutive patients with B-cell NHL with no clinical and/or laboratory findings of cryoglobulinemia, 142 NHL/HCV- and 108 NHL/HCV+ with chronic hepatitis (CH), 120 consecutive subjects with HCV-related CH, and 110 age, sex-matched healthy blood donors. The frequency of the IL-10(-1082GG) genotype vs remaining genotypes (IL-10(-1082GA/AA)) was higher in NHL/HCV+ patients than HCV-related CH patients (P=0.0002, OR=2.89, CI: 1.62-5.15) and in NHL/HCV+ than NHL/HCV- patients (P=0.0001, OR=2.99, CI: 1.72-5.19). Moreover, the IL-10(-1082GG) genotype was more prevalent in indolent NHL/HCV+ cases than aggressive NHL/HCV+ (P=0.0004, OR=4.97, CI: 2.10-11.79). Finally, we confirmed that IL-10(-1082GG) genotype is associated with higher IL-10 production compared to AA homozygous (P=0.037). CONCLUSIONS: The high IL-10 production, due to IL-10(-1082GG) genotype, influences the clinical expression of the HCV infection by increasing susceptibility to develop NHL and might contribute to the indolent form of the disease.     

Hepatic Steatosis in Hepatitis C Virus Genotype 3 Infection: Does It Correlate with Body Mass Index, Fibrosis, and HCV Risk Factors?

Hepatic steatosis is a recognized feature of hepatitis C viral infection, particularly in genotype 3. The demographics and the associations contributing to moderate to severe steatosis in genotype 3 are not very well studied. The aim of this study is to determine the demographics and association of steatosis with fibrosis, obesity, diabetes, lipid levels, and risk factors among patients with hepatitis C virus (HCV) genotype 3. Two hundred ninety-three consecutive HCV patients (genotype 1, n = 218; genotype 2, n = 43; genotype 3, n = 32) at our institution were studied retrospectively. Demographic information such as height, weight, genotype, risk factors, serum cholesterol and triglyceride, and liver biopsy was collected. Steatosis was graded using the Brunt classification. HCV genotype 3-infected patients were younger (P < 0.04) and had lower serum cholesterol levels (P < 0.02) compared to nongenotype 3 patients. Moderate to severe steatosis was more prevalent in HCV genotype 3 patients (P < 0.001) with intravenous drug abuse as a risk factor (P = 0.04). Genotype 3 was the independent predictor of steatosis in all patients. There was no statistical association between grade of steatosis and body mass index, fibrosis, necroinflammation, or hyperlipidemia when only HCV genotype 3 patients were included in the multivariate logistic model. Hepatic steatosis is a feature of genotype 3. Patients with HCV genotype 3 are younger and have lower serum cholesterol levels. Genotype 3 is the independent predictor for steatosis in HCV patients. HCV genotype 3 patients with moderate to severe steatosis are more likely to have intravenous drug use as a risk factor.     

Prospective study of risk factors for hepatitis C virus acquisition by Caucasian, Hispanic, and Asian American patients

Commonly known risk factors for infection with hepatitis C virus (HCV) include blood transfusion, injection drug use, intranasal cocaine use, and body tattoos. We hypothesized that Asian Americans infected with HCV may not identify with these established risk factors present in Caucasians and Hispanics, and our aim was to conduct a survey of risk factors in HCV-infected patients in these ethnic groups. In this prospective study, 494 patients infected with HCV completed a detailed risk assessment questionnaire at a liver centre in Northern California from 2001 to 2008. Among subjects participating in this study, 55% identified themselves as Caucasian, 20% as Hispanic, and 25% as Asian. Asian Americans were older, less likely to smoke or consume alcohol, and have a family history of cancer compared with Caucasians and Hispanics. The laboratory profiles were similar, and genotype 1 was the most common infection in all groups (74-75%). The great majority of Caucasians (94%) and Hispanics (86%) identified with commonly known risk factors, which was in contrast to 67% of Asians (P < 0.0001). The most common risk factors in Asians were blood transfusions (50%) and acupuncture (50%). Furthermore, 74% of Caucasians and 66% of Hispanics identified more than one major risk factor, while only 20% of Asians reported having more than one risk factor (P < 0.0001). Survey for established risk factors for acquisition of HCV may be more appropriate for risk assessment of Caucasians and Hispanics, but not for Asian Americans. These findings may guide the development of HCV screening in our increasingly diverse population.     

Hepatitis C virus genotypes in France: relationship with epidemiology, pathogenicity and response to interferon therapy. The GEMHEP

The aim of this study was to investigate the following in a large population of French patients with chronic hepatitis C: the geographical distribution of hepatitis C virus (HCV) genotypes; the relationship between HCV genotypes and epidemiological characteristics; severity of the disease; and response to interferon (IFN) therapy. Data from 14 tertiary referral centres, corresponding to 1872 patients with chronic hepatitis C, were prospectively collected from 1989 to 1997. HCV genotyping was performed using the line probe assay (LiPA). HCV genotypes 1b, 3, 1a, 2, 4 and a mixed infection were found in 41%, 22%, 16%, 11%, 4% and 4% of our population, respectively. HCV genotype distribution was homogeneous, except for genotype 2 that was found more frequently in the southwest than in the other regions (21% vs 9.2%) ( P =0.001). HCV distribution was associated with gender, age, and source and duration of infection. In multivariate analysis, these correlations were related to the source of infection, which was the only independent factor significantly associated with genotype ( P =0.001). Genotype 1b was significantly more common in patients with cirrhosis, but in multivariate analysis cirrhosis was independently related to older age at exposure and longer duration of infection ( P =0.001). A sustained response to IFN therapy was observed in 11% of patients infected with genotypes 1a or 1b vs 32% of those infected with genotypes 2 or 3 ( P =0.001). This study shows that HCV genotype is mainly related to the source infection, but not to the intrinsic pathogenicity of HCV, and is a strong predictor of sustained response to therapy.     

Distribution frequency of hepatitis C virus genotypes in 2231 patients in Iran

Aim: Given the importance of frequency distribution of HCV genotypes, we studied genotypic distribution of HCV in Iran. In this cross-sectional study, 2231 patients with hepatitis C who presented in hepatitis clinics in Tehran were investigated for HCV genotypes. Methods: Genotyping was performed by genotype specific primers. Results: The highest frequency was for genotype 1a, with 886 (39.7%) of subjects. Genotype 3a and 1b were the other frequent genotypes, with 613 (27.5%) and 271 (12.1%) subjects, respectively. Of the samples, 401 (18%) had an undetermined genotype. Mixed genotypes were also found in 33 samples (1.6%). Genotype 1b frequency in patients under 20 years old was 10.2%, while its frequency in patients over 60 years old was 18.5%. Genotype 1b frequency significantly increased by age (P = 0.02). Conclusion: This study indicates that the dominant HCV genotype among patients living in Tehran was 1a.     

The role of diabetes in hepatocellular carcinoma: a case-control study among United States Veterans

OBJECTIVE: Diabetes mellitus (DM) has been reported to increase the risk of hepatocellular carcinoma (HCC). We carried out a case-control study to examine the role of DM while controlling for several known risk factors of HCC. METHODS: All hospitalized patients with primary liver cancer (PLC) during 1997-1999 were identified in the computerized database of the Department of Veterans Affairs, the Patient Treatment File. Controls without cancer were randomly assigned from the Patient Treatment File during the same time period. The inpatient and outpatient files were searched for several conditions including DM, hepatitis C virus (HCV), hepatitis B virus (HBV), alcoholic cirrhosis, autoimmune hepatitis, hemochromatosis, and nonspecific cirrhosis. Adjusted odds ratios (OR) were calculated in a multivariable logistic regression model. RESULTS: We identified 823 patients with PLC and 3459 controls. The case group was older (62 yr [+/-10] vs 60 [+/-11], p < 0.0001), had more men (99% vs 97%, 0.0004), and a greater frequency of nonwhites (66% vs 71%, 0.0009) compared with controls. However, HCV- and HBV-infected patients were younger among cases than controls. Risk factors that were significantly more frequent among PLC cases included HCV (34% vs 5%, p < 0.0001), HBV (11% vs 2%, p < 0.0001), alcoholic cirrhosis (47% vs 6%, p < 0.0001), hemochromatosis (2% vs 0.3%, p < 0.0001), autoimmune hepatitis (5% vs 0.5%, p < 0.0001), and diabetes (33% vs 30%, p = 0.059). In the multivariable logistic regression, diabetes was associated with a significant increase in the adjusted OR of PLC (1.57, 1.08-2.28, p = 0.02) in the presence of HCV, HBV, or alcoholic cirrhosis. Without markers of chronic liver disease, the adjusted OR for diabetes and PLC was not significantly increased (1.08, 0.86-1.18, p = 0.4). There was an increase in the HCV adjusted OR (17.27, 95% Cl = 11.98-24.89) and HBV (9.22, 95% CI = 4.52-18.80) after adjusting for the younger age of HCV- and HBV-infected cases. The combined presence of HCV and alcoholic cirrhosis further increases the risk with an adjusted OR of 79.21 (60.29-103.41). The population attributable fraction for HCV among hospitalized veterans was 44.8%, whereas that of alcoholic cirrhosis was 51%. CONCLUSION: DM increased the risk of PLC only in the presence of other risk factors such as hepatitis C or B or alcoholic cirrhosis. Hepatitis C infection and alcoholic cirrhosis account for most of PLC among veterans.     

Geographical distribution of HCV genotypes in Mexico

Chronic hepatitis C (CHC) is the second cause of endstage liver disease in our country and one of the main indications of liver transplantation. Hepatitis C virus (HCV) genotype is the principal prognostic factor and the determinant of the therapeutic scheme. In our country few data exist regarding the prevalence of HCV infection and genotype distribution in the Mexican Republic has not been determined. The aim of this study was to characterize the prevalence of the different HCV genotypes and to explore their geographical distribution. Methods: Mexican patients with hepatitis C infection, detected throughout the country between 2003 and 2006, were included. All samples were analyzed by a central laboratory and Hepatitis C genotype was identified by Line Immuno Probe Assay in PCR positive samples (Versant® Line Probe Assay Quest Diagnostics Nichols Institute, San Juan Capistrano CA). Data were analyzed according to the four geographical areas in Mexico. Results: One thousand three hundred and ninety CHC patients were included. The most frequent genotype detected was genotype 1 (69%) followed by genotype 2 (21.4%) and genotype 3 (9.2%). Genotype 4 and 5 were infrequent. There was no subject infected with genotype 6. Genotype 1 and 2 exhibit very similar distribution in all geographical areas. Genotype 3 infected patients were more frequent in the North region (52%) compared with other areas: center-western (30%), center (17%), South-South east (1%) (p < 0.001). Conclusions: The most prevalent HCV genotype in Mexico is genotype 1. Geographical distribution of HCV genotypes in the four geographical areas in Mexico is not homogenous with a greater frequency of genotype 3 in the north region. This difference could be related to the global changes of risk factors for HCV infection.     

High prevalence of hepatitis C virus infection in Belgian intravenous drug users and potential role of the "cotton-filter" in transmission: the GEMT Study

AIMS: To estimate viral seroprevalences for HCV, HBV and HIV among belgian intravenous (IVDU) and non intravenous (non-IVDU) drug users; to assess risk factors for HCV infection in IVDU; to assess feasibility of chronic hepatitis C follow-up in this population. DESIGN: Cross-sectional study. Demographic and behavioural characteristics were obtained by a standardized questionnaire. Serum samples were tested for HCV, HBV and HIV. SUBJECTS AND SETTING: 329 patients (244 IVDU and 85 non-IVDU) attending ten general practitioners in 1995. RESULTS: HCV seroprevalence was 78.3%; it was 35.7% for HBV and 0.9% for HIV in IVDU, vs 2.4%, 8.3% and 0%, respectively, in non-IVDU. In logistic regression analysis, independent risk factors for HCV infection were: 1/sharing of syringes and/or of "cottons" used as filters (adjusted prevalence odds ratio [POR] = 31.7; 95% confidence interval [CI] = 9.8-102.5), 2/duration of injecting upper than one month (adjusted POR = 8.6; CI = 3.0-24.7) and 3/age (adjusted POR = 1.2 by year of difference; CI = 1.0-1.3). A biochemical follow-up was obtained in 70% of HCV seropositive users; 79.5% of them had chronic hepatitis C (mean value of ALT = 3.5 times upper normal value, range 1.1-23.0). Among these, 24.7% went through liver biopsy during the three years follow-up period of the study. CONCLUSIONS: HCV seroprevalence is very high among belgian IVDU. Prevention strategies have to focus on neophytes injectors. They must be urgently revisited for what concern needles/syringes exchange programs: "cottons" must be included. Follow-up and treatment of chronic hepatitis C seem to be poorly effective among drug users.     

A Comparison of Risk Factors for HCV-mono-infection,HIV-mono-infection,and HCV/HIV-co-infection in a Community Setting

The prevalence of HIV infection in HCV patients is much lower than the prevalence of HCV infection in HIV patients. Whereas the higher prevalence of HCV infection in HIV is clearly related to drug abuse, the reasons for the lower prevalence of HIV infection in HCV patients has not been reported. The prevalence of non-sexual and sexual risk factors associated with acquisition of hepatitis C and HIV were studied in HIV-mono-infected, HCV-mono-infected, and HCV/HIV-co-infected individuals. None of the 114 HCV-mono-infected patients tested positive for HIV and this finding was associated with a significantly lower number of men who have sex with men (MSM) among the HCV-mono-infected subjects than among either the HIV-mono-infected or HCV/HIV-co-infected individuals. Unprotected anal intercourse and sex for money or drugs were reported less often by HCV-mono-infected individuals than by HIV-mono-infected and HCV/HIV-co-infected subjects. Having sex with an intravenous-drug user (IVDU) was reported more frequently by both HCV-mono-infected and HCV/HIV-co-infected individuals than by HIV-mono-infected individuals. Sub-analysis of the group of MSM revealed that IVDU differentiated between HIV-mono-infected and HCV/HIV-co-infected subjects. These results reveal that the lower prevalence of HIV in HCV patients is related to a lower number of MSM in this group and that sex with an IVDU is a surrogate marker for drug abuse related to acquiring HCV but not HIV. The guidelines should include strategies for testing for HCV and HIV in patients with these infections.