Molecular evidence of male-to-female sexual transmission of hepatitis C virus after vaginal and anal intercourse

Hepatitis C Virus among Female Sex Workers: A Cross-Sectional Study Conducted along Rivers and Highways in the Amazon Region

Background: Previous studies found a high prevalence of pathogens among female sex workers (FSWs) in the Amazon region, and established their parenteral and sexual transmission. This study estimated the prevalence of hepatitis C virus (HCV) infection and associated risk factors, and the frequency of HCV genotypes and resistance-associated substitutions (RASs) in this vulnerable group. Methods: Distinct sampling methods were used to access 412 FSWs in cities and riverside communities in the Amazon region from 2015 to 2018. Three methods for HCV diagnosis were used to determine infection status. HCV genotypes and RASs were identified by sequencing and nucleotide fragment analysis. An association between HCV infection and exposure factors was determined by bivariate and multivariate analysis. Results: In total, 44 (10.7%) FSWs were exposed to HCV, and 32 (7.8%) of them had active infection. Nine socioeconomic characteristics and risky sexual behaviors were associated with HCV exposure, particularly unprotected sex and condom exemption for the clients who paid extra money. Genotype 1 (81.3%) and 3 (18.7%) were detected. The frequency of FSWs with RASs was 23.1% (6/26) for grazoprevir related to the occurrence of substitutions Y56F and S122G. Conclusions: HCV infection among FSWs is highly prevalent and dominated by genotype I. Urgent preventive and treatment measures are required to reduce HCV infection in FSWs and the general population.

QUENTIN: reconstruction of disease transmissions from viral quasispecies genomic data

Motivation

Genomic analysis has become one of the major tools for disease outbreak investigations. However, existing computational frameworks for inference of transmission history from viral genomic data often do not consider intra-host diversity of pathogens and heavily rely on additional epidemiological data, such as sampling times and exposure intervals. This impedes genomic analysis of outbreaks of highly mutable viruses associated with chronic infections, such as human immunodeficiency virus and hepatitis C virus, whose transmissions are often carried out through minor intra-host variants, while the additional epidemiological information often is either unavailable or has a limited use.

Results

The proposed framework QUasispecies Evolution, Network-based Transmission INference (QUENTIN) addresses the above challenges by evolutionary analysis of intra-host viral populations sampled by deep sequencing and Bayesian inference using general properties of social networks relevant to infection dissemination. This method allows inference of transmission direction even without the supporting case-specific epidemiological information, identify transmission clusters and reconstruct transmission history. QUENTIN was validated on experimental and simulated data, and applied to investigate HCV transmission within a community of hosts with high-risk behavior. It is available at https://github.com/skumsp/QUENTIN.

Contact

pskums@gsu.edu or alexz@cs.gsu.edu or rahul@sfsu.edu or yek0@cdc.gov.

Supplementary information

Supplementary data are available at Bioinformatics online.

Sexual Transmission of Hepatitis C Virus Between HIV Infected Subjects and Their Main Heterosexual Partners

BACKGROUND

Overall, 60-70% of the hepatitis c virus (HCV) transmission routes is parenteral, and in 30-40% of the cases is unknown (e.g. sexual route). Knowing these routes in HIV infected dyads is very important due to clinical and methodological reasons.

OBJECTIVES

The present study aimed to identify and quantitatively investigate HIV-infected individuals and their main heterosexual partners regarding the risk factors of HCV transmission.

PATIENTS AND METHODS

One hundred sixty eight of 984 couples were chosen through random generated numbers using a computer program from behavioral consultation center in Shiraz, Iran. We used actor partner independent model (APIM) and multilevel analysis to assess multiple risk factors for HCV, while partitioning the source of risk at the individual and couple levels.

RESULTS

Age of the index samples was 38.71 ± 7 years, and 33.2 ± 6.3 for their main heterosexual partners; the mean duration of sexual relationship for couples was 11.9 (median = 8.5) years. Multivariate analysis showed that actor risk factor of intravenous drug using (IDU) (AOR= 13.03; 95% CI: 3.9- 43.82) and actor cofactors of HIV positivity (AOR = 7.1; 95% CI: 1.37- 36.97), razor sharing (AOR = 4.81; 95% CI: 1.84- 12.55), sex (AOR = 8.83; 95% CI: 3.16- 24.87), and condom use in sexual activity with main partner (AOR = 0.15; 95% CI: 0.02- 0.44) were associated with actor HCV positivity.

CONCLUSIONS

Health care providers need to pay special attention to sexual transmission of HCV among HIV-infected individuals, and should recommend control/preventive measures for HCV sexual transmission.

Hepatitis C virus and human immunodeficiency virus transmission routes: Differences and similarities

Bouare et al found that hepatitis C virus (HCV) infection in Malian women is mainly transmitted through medical procedures with contaminated supplies, and that human immunodeficiency virus (HIV) transmission is predominantly sexual. The results of this study confirm those of a recent case-control study in New York and Oregon which demonstrated that healthcare exposures represent an important source of new HCV infections in United States. HCV seroprevalence was only 0.2% in pregnant, young Malian women, indicating that hygiene improved in healthcare facilities over time. Heterosexual transmission of HCV is exceptional, and can occur, from males to females, in extremely rare occasions in case of vaginal mucosal damage or less rarely through anal intercourse. The Malian study did not show an association between HIV infection and hospitalization, transfusion, tattoo, dental care. Transmission by needle-stick injury occurs in 0.9%-2.2% of exposures from HCV-infected subjects and in 0.1%-0.3% of exposures from HIV-infected individuals. HCV is therefore more transmissible through percutaneous exposure.

Acute hepatitis C virus in an HIV clinic: a screening strategy, risk factors, and perception of risk

Acute hepatitis C virus (HCV) infection is being acquired undetected among HIV-infected individuals. A practical way to regularly screen HIV-infected patients for acute HCV irrespective of perceived risk or symptoms is needed. We piloted implementation of an acute HCV screening strategy using routine HIV clinical care schedules and the least costly blood tests, in a Rhode Island HIV care center. Study participants had ongoing HCV risk, completed questionnaires encompassing risk behaviors and perception of risk, and were screened with quarterly alanine aminotransferase (ALT). ALT rise triggered HCV RNA testing, with pooled rather than individual specimen HCV RNA testing for underinsured participants. Participants were primarily older, college-educated men who have sex with men (MSM) with history of sexually transmitted infection other than HIV. One of 58 participants developed acute HCV in 50 person-years of observation for an annual incidence of 2.0% per year (95% confidence interval [CI] 0.05-11.1%). The majority (54%) of MSM did not perceive that traumatic sexual and drug practices they were engaging in put them at risk for HCV. Unprotected sex often occurred under the influence of drugs or alcohol. Self-reported HCV risk and participation in several risk behaviors declined during the study. It was possible to collect frequent ALTs in a busy HIV clinic with 71% of total projected ALTs obtained and 88% of participants having at least one ALT during the 9-month follow-up period. All instances of ALT rise led to reflexive HCV RNA testing. Tracking quarterly ALT for elevation to systematically prompt HCV RNA testing before seroconversion is a promising approach to screen for acute HCV in a real-world HIV clinical setting.

Cellular immune responses and occult infection in seronegative heterosexual partners of chronic hepatitis C patients

It is unknown whether hepatitis C virus (HCV)-specific cellular immune responses can develop in seronegative sexual partners of chronically HCV-infected patients and whether they have occult infection. Thirty-one heterosexual partners of patients with chronic HCV were studied, fifteen of them with HCV transmission risks. Ten healthy individuals and 17 anti-HCV seropositive patients, without viremia, were used as controls. Virus-specific CD4+ and CD8+ T-cell responses were measured by flow cytometry against six HCV peptides, situated within the nonstructural (NS) proteins NS3, NS4 and NS5, through intracellular detection of gamma interferon (IFN-γ) or interleukin 4 (IL-4) production and CD69 expression. Sexual partners had a higher production of IFN-γ and IL-4 by CD4+ cells against NS3-p124 (P = 0.003), NS5b-p257 (P = 0.005) and NS5b-p294 (P = 0.012), and CD8+ cells against NS3-p124 (P = 0.002), NS4b-p177 (P = 0.001) and NS3-p294 (P = 0.004) as compared with healthy controls. We observed elevated IFN-γ production by CD4+ T cells against NS5b-p257 (P = 0.042) and NS5b-p294 (P = 0.009) in the sexual partners with HCV transmission risks (sexual, professional and familial altogether) than in those without risks. RNA was extracted from peripheral blood mononuclear cells (PBMC), and detection of HCV-RNA positive and replicative (negative) strands was performed by strand-specific real-time PCR. In four sexual partners, the presence of positive and negative HCV- RNA strands in PBMC was confirmed. Hence, we found an HCV-specific cellular immune response as well as occult HCV infection in seronegative and aviremic sexual partners of chronically HCV-infected patients.

Characteristics of HIV-infected women and factors associated with HCV seropositivity in the Republic of Georgia

BACKGROUND

The aim of this study was to describe the extent of the HIV epidemic among women in the Republic of Georgia and to identify factors associated with HCV co-infection in this population.

FINDINGS

All women aged ≥18 years who were diagnosed with HIV between 1989 and 2006 were identified through the National HIV/AIDS surveillance database. Medical records were reviewed for demographic characteristics, risk factors and HCV serostatus. A total of 249 women were identified. Only 4% declared injection drug use (IDU); sex work was reported by 9%. Substantial risk factors were identified among the women's sexual partners, nearly 69% of whom were IDUs, 84% were HIV positive and 66% HCV positive. Seventeen percent of women were seropositive for HCV. Factors significantly associated with HCV seropositivity in bivariate analyses among non-IDU women were partner IDU+ [Prevalence ratio (PR): 4.5 (95% CI: 1.4, 14.2)], and partner HCV+ [PR: 7.2 (95% CI: 1.8, 29.5)].

CONCLUSIONS

The HIV epidemic in the Republic of Georgia is closely tied to the IDU community. Evidence-based interventions targeting IDU and partners of IDU are urgently required to halt the spread of the HIV epidemic in the country.

Hepatitis C virus resistance to protease inhibitors

Recent advances in molecular biology have led to the development of novel small molecules that target specific viral proteins of the hepatitis C virus (HCV) life cycle. These drugs, collectively termed directly acting antivirals (DAA) against HCV, include a range of non-structural (NS) 3/NS4A protease, NS5B polymerase, and NS5A inhibitors at various stages of clinical development. The rapid replication rate of HCV, along with the low fidelity of its polymerase, gives rise to generations of mutations throughout the viral genome resulting in remarkable sequence variation in the HCV population, known as a quasispecies. The efficacy of DAAs is limited by the presence of those mutations that give rise to amino-acid substitutions within the targeted protein, and that affect the viral sensitivity to these compounds. Thus, due to the high genetic variability of HCV, variants with reduced susceptibility to DAA can occur naturally even before treatment begins, but usually at low levels. Not surprisingly then, these changes are selected in patients either breaking through or not responding to potent DAA treatment. In vitro or in vivo, six major position mutations in the NS3 HCV protease (36, 54, 155, 156, 168, and 170) have now been reported associated with different levels of resistance. The amino acid composition at several of the drug resistance sites can vary between the HCV genotypes/subtypes, resulting in different consensus amino acids leading to a reduction in replicative fitness as well as reduced DAA sensitivity. Different amino acid diversity profiles for HCV genotypes/subtypes suggest differences in the position/type of immune escape and drug resistance mutations. Also, different pathways of resistance profiles based on the chemical scaffold (linear or macrocyclic) of the protease inhibitors have been described. This review first describes how resistance to a protease inhibitor can develop and then provides an overview of the mechanism of how particular mutations confer varying levels of resistance to protease inhibitor, which have been identified and characterized using both genotypic and phenotypic tools. Future potential therapeutic strategies to assist patients who do develop resistance to protease inhibitors are also outlined. The challenge developing new HCV protease inhibitors should take into consideration not only the antiviral potency of the drugs, the occurrence and importance of side effects, the frequency of oral administration, but also the resistance profiles of these agents.

Is sexual contact a major mode of hepatitis C virus transmission?

Medical opinion varies considerably regarding the transmission of hepatitis C virus (HCV) through sexual contact. Based on the study design, representativeness of the study population, and the methods used for case ascertainment, we analyzed 80 qualifying reports regarding the evidence for or against sexual transmission. Regarding heterosexual transmission, the weight of evidence is that there is no increased risk of sexual transmission of HCV among heterosexual couples in regular relationships. This risk increases among persons with multiple sexual partners (adjusted odds ratio [aOR] 2.2-2.9), but this association may be confounded by increased likelihood of injection drug use with increased number of partners. There appears to be a real increased risk for women coinfected with human immunodeficiency virus (HIV) or other sexually transmitted infections (aOR 3.3-3.9) and especially for HIV-infected gay men who are having sex with one another compared with HIV-uninfected men (aOR 4.1-5.7). HIV-infected gay men increase their risk of such transmission in association with practices that lead to mucosal trauma (multiple sexual partners, fisting, use of sex toys) and the presence of genital ulcerative disease.

CONCLUSION

This review should inform, and not distract from, recommendations to reduce the risk of HCV transmission. Health care providers need to pay special attention to sexual transmission of HCV among HIV-infected individuals.

Acute hepatitis C infection with evidence of heterosexual transmission

A 62-year-old woman acquired acute hepatitis C virus (HCV) infection after heterosexual contact with a known HCV positive former injecting drug user. There were no known sexual or other risk factors for HCV acquisition. Phylogenetic analysis confirmed the case and index were infected with identical genotype 3a strains, consistent with heterosexual transmission in the absence of specific risk factors.

Seminal fluid ribavirin level and functional semen parameters in patients with chronic hepatitis C on antiviral combination therapy

BACKGROUND & AIMS

Due to the possible teratogenic effect of ribavirin, effective contraception is mandatory during antiviral therapy in patients with chronic hepatitis C (CHC). The aim of this study was to evaluate seminal parameters and ribavirin and HCV-RNA concentrations in seminal fluid and serum prior to and during antiviral treatment.

PATIENTS AND METHODS

Fifteen male patients (age: 42+/-9 (years+/-SD)) with CHC treated with pegylated interferon-alpha-2a and ribavirin were investigated. Seminal fluid (sperm concentration, motility, and morphology) was analysed morphologically. HCV-RNA and ribavirin concentration were determined by quantitative PCR and HPLC, respectively. Examinations were carried out at baseline, week 4, and week 12.

RESULTS

Ribavirin concentration was higher in seminal fluid than in serum (week 4: 5.2+/-2.5 vs. 2.1+/-0.3; week 12: 4.4+/-1.8 vs. 2.0+/-0.3 (microg/ml, mean+/-SD; p<0.001)). Semen abnormalities were common at baseline (asthenoteratozoospermia: n=6; asthenozoospermia: n=3; teratozoospermia: n=3). Sperm density (BL: 67+/-33x10(6)/ml; week 4: 42+/-25 (p<0.05); week 12: 49+/-33 (n.s.)), percentage of sperm with progressive motility (BL: 40+/-26%; week 4: 27+/-25; week 12: 31+/-20 (n.s.)), and percentage of sperm with normal morphology (BL: 25+/-15; week 4: 20+/-11; week 12: 16+/-9; p<0.05 for both) further decreased during antiviral therapy. HCV-RNA was detectable in the seminal fluid of only two patients prior to antiviral therapy and was undetectable in all patients during combination therapy.

CONCLUSION

Semen abnormalities were common in CHC patients, with further impairment during antiviral therapy. Ribavirin concentration was elevated twofold in seminal fluid compared to serum levels, which reinforces the need for contraception during antiviral combination therapy.

Factors associated with prevalent hepatitis C infection among HIV-infected women with no reported history of injection drug use: the Women's Interagency HIV Study (WIHS)

Although the primary mode of hepatitis C virus (HCV) transmission is exposure to blood products or injection drug use (IDU), studies have found varying independent risk factors for HCV infection among persons with no history of IDU or exposure to blood products. For HIV-infected women, sexual transmission may be another potential source of HCV infection. HIV-infected and HIV-negative women at risk for HIV enrolled in the Women's Interagency HIV Study (WIHS) during October 1994 to November 1995 and again between October 2001 and November 2002 were studied. Clinical and demographic factors associated with HCV seroprevalence were assessed in multivariate logistic regression models controlling for history of blood transfusion and IDU. Among 3636 women with HCV results, 31.5% were HCV antibody positive (HCV+) including 13.5% with no reported history of IDU or blood transfusions. Multivariate logistic regression analyses stratified on IDU showed that among women with no history of IDU, sex with an IDU male was independently associated with HCV positivity (odds ratio [OR] = 2.8, 95% confidence [CI] = 2.1, 3.8, p < 0.0001) after controlling for blood transfusion, age, HIV infection, unemployment, birth in the United States, history of hepatitis B infection, and current smoking status. Further stratification on HIV status showed that the association was significant only for the HIV+ (OR = 1.9, 95% CI = 1.3, 2.7, p = 0.0007) compared to the HIV- women (OR = 1.1, 95% CI = 0.4, 2.7) although these odds ratios were not significantly different (p = 0.25). For HIV-positive women with no reported history of IDU, sex with an IDU male was independently associated with HCV suggesting that sexual transmission may be an important mode of HCV transmission for these high-risk women.

Molecular analysis of transmission of hepatitis C virus in a nurse who acquired acute hepatitis C after caring for a viremic patient with epistaxis

A 23-year-old nurse (HC-IP) developed acute hepatitis C. Intrafamilial transmission of hepatitis C virus (HCV) was suspected initially because her parents were carriers of HCV of the same genotype (1b) as that of Patient HC-IP. However, the HCV isolate from Patient HC-IP and those from her parents shared identities of only 92.4-92.7% in the 1,087-nucleotide (nt) sequence within the NS5B region. It was then suspected that she contracted HCV infection during medical practice. Sixteen patients with antibodies to HCV (anti-HCV) were hospitalized 1-3 months before she became positive for anti-HCV. Upon analysis of stored serum samples, 14 of the 16 patients were found to be positive for HCV RNA, and 9 of the 14 viremic patients had genotype 1b HCV. Although the shared identities between the HCV isolate from Patient HC-IP and those from eight of the nine patients were merely 90.6-93.9% within the 1,087-nt NS5B sequence, the HCV isolate from the remaining one patient (HC-P12) was 99.7% identical to that from Patient HC-IP. Upon analysis of the E1 and E2 junctional region including hypervariable region 1 (283 nt), there was a close relationship (99.3-100%) between clones obtained from Patients HC-IP and HC-P12. Although the nurse HC-IP had a finger injury, she took care of Patient HC-P12, a 70-year-old man with HCV-related cirrhosis and recurrent epistaxis, occasionally without wearing protective gloves. This study indicates the occurrence of HCV transmission by exposure of nonintact skin to blood in health care settings.

Sexually transmitted hepatitis C virus superinfection in HIV/hepatitis C virus co-infected men who have sex with men

We report two cases of sexually transmitted hepatitis C virus (HCV) superinfection in HIV/HCV-co-infected patients with high-risk sexual behaviour. The two patients had chronic HCV and a history of sexually transmitted infections. HCV superinfection was confirmed by phylogenetic analysis. No risk factors for HCV were found except unprotected anal sex with multiple casual male partners. HCV serology and serum HCV RNA should be examined periodically in HIV-infected men who have sex with men engaging in high-risk sexual behaviours.

Complete genomes for hepatitis C virus subtypes 6f, 6i, 6j and 6m: viral genetic diversity among Thai blood donors and infected spouses

In this study, the first complete genome sequences for hepatitis C virus (HCV) subtypes 6f, 6i, 6j and 6m, obtained from infected blood donors in Chiang Mai, Thailand, are reported. Pairwise genome-wide nucleotide similarities between some of these isolates were higher than the 75-80% value used previously to define different HCV subtypes. To investigate further, the entire genomes of four prototype isolates, Th602 (6i), Th553 (6j), B4/92 (6m) and D86/93 (6n), were sequenced. Pairwise comparison of these sequences gave a similar range of nucleotide similarities, thereby providing new information for HCV subtype classification. In order to study the hypothesis of interspousal HCV transmission, four additional complete HCV genome sequences were obtained from two infected Thai blood donors and their spouses, C-0044 and C-0046 (6f), and C-0192 and C-0185 (6m). Pairwise comparison of the sequences revealed that C-0044 and C-0046 share a nucleotide similarity of 98.1%, whilst C-0185 and C-0192 have a similarity of 97.8%. Several other studies of partial HCV sequences of different genomic regions from HCV-infected couples have shown nucleotide similarities ranging from 96.3 to 100%. The similarities of the complete genome sequences from the two couples in the current study are consistent with HCV transmission between spouses.

Hepatitis C virus infection among methamphetamine-dependent individuals in outpatient treatment

Research on the relationship between illicit drug use and infectious diseases have primarily focused on the major problem of heroin injection and HIV transmission. Over the past decade, however, research have shown that rates of hepatitis C infection among injection drug users have surpassed those of HIV infection. There has been little systematic study on the relationship between hepatitis C virus (HCV) and the role of methamphetamine (MA) use in the transmission of the virus. This study examined the prevalence of hepatitis C infection among a sample of 723 MA-dependent individuals who sought outpatient treatment from 1999 through 2005. Roughly 15% of the total sample and 44% of the injectors were found to be infected with HCV. Controlling for participant characteristics, we found through multiple logistic regression analyses that HCV infection was more associated with injection use, older age, and female sex. Findings suggest a need for targeted education and prevention efforts about hepatitis C among high-risk MA users, including HCV testing coupled with referrals to HCV treatments.

Increase in hepatitis C virus incidence in HIV-1-infected patients followed up since primary infection

BACKGROUND

An increase in the incidence of sexually transmitted infections and hepatitis C virus (HCV) infections in HIV-infected men who have sex with men (MSM) has recently been reported.

OBJECTIVE

To estimate HCV incidence and risk factors among HIV-1-infected patients followed up since primary HIV infection in the French PRIMO Cohort between 1996 and 2005.

PATIENTS AND METHODS

All patients with at least 18 months of follow-up were studied. HCV antibody tests were performed on baseline plasma samples and repeated on the latest available sample when negative at baseline.

RESULTS

In total, 402 patients with a median follow-up of 36 (range 18-104) months were eligible. HCV seroconversion was observed in 6 patients (4 men and 2 women), corresponding to an HCV incidence rate of 4.3 per 1000 person-years. Incidence rates in men and women were 3.5 and 7.8 per 1000 person-years, respectively. The incidence rate was 1.2 per 1000 person-years before January 2003 and 8.3 per 1000 person-years after January 2003 (p = 0.06). The classic risk factors for HCV infection were found in women (intravenous drug use, and body piercing), whereas the only identified risk factor for HCV acquisition was unsafe sex in the four men.

CONCLUSIONS

Increase in the incidence of acute HCV infection in recently HIV-infected patients confirms the shift in sexual behaviour in the recent years, especially in HIV-infected MSM. Repeated testing for HCV antibodies should be carried out in HCV-negative HIV-infected patients and specific recommendations about protected sex should be clearly provided.

Use of a novel washing method combining multiple density gradients and trypsin for removing human immunodeficiency virus-1 and hepatitis C virus from semen

OBJECTIVE

To determine the effectiveness of a novel treatment designed to remove human immunodeficiency virus (HIV) -1 and hepatitis C virus (HCV) from spiked semen and to evaluate sperm motility and viability after treatment.

DESIGN

A prospective clinical laboratory-based study.

SETTING

The human studies were conducted in academic and national research environments. The bovine study was conducted in an accredited research facility.

PATIENT(S)

Healthy volunteers provided the semen samples used in the human studies; abattoir-derived material was used for the bovine embryo production study.

INTERVENTIONS(S)

None.

MAIN OUTCOME MEASURE(S)

Cytopathic, reverse transcriptase-polymerase chain reaction, and branched DNA assays were used to test the efficacy of the procedure for inactivating or removing viruses from spiked semen; standard semen evaluation criteria were used to assess the effects of the procedures on sperm motility and viability.

RESULT(S)

Trypsin exposure significantly reduced the infectivity of HIV-1. The triple density gradient treatment, with or without trypsin, had no detrimental affect on fresh or cryopreserved/thawed sperm 2-48 hours after treatment. The treatment of semen spiked with HIV-1 or HCV indicated that the procedure was effective for reducing viral copies to undetectable levels or below levels of clinical relevance.

CONCLUSION(S)

The procedure was effective for significantly inactivating or reducing HIV-1 and HCV in spiked semen without adversely affecting sperm quality.

Medically assisted procreation and transmission of hepatitis C virus: absence of HCV RNA in purified sperm fraction in HIV co-infected patients

OBJECTIVE

The risk of hepatitis C virus (HCV) transmission in medically assisted procreation (MAP) is debated and some researchers have proposed to exclude MAP for HCV-positive infertile patients. The objectives of this study were to assess the presence of viral RNA in the final preparation of density gradient semen fractions collected from men with chronic HCV and HIV co-infection participating in a MAP program, and to assess whether HIV co-infection influences the rate of the presence of HCV RNA in the semen.

DESIGN AND METHODS

The study was based on a cohort of 170 HCV-infected male patients (93 HIV co-infected) participating in a MAP program in a French center. Semen samples were subjected to standard MAP sperm preparation, using density-gradient centrifugation with 40 and 90% layers. All aliquots were tested with a commercially available HCV RNA assay (Roche Monitor), adapted for use with semen after a nucleic HCV RNA extraction modification (Organon Technika).

RESULTS

Seminal plasma samples from 19 (11%) patients were HCV RNA positive. The positive HCV viral load in semen was less than 600 IU/ml. None of the 90% fractions from HCV-infected patients were HCV RNA positive. Among the 93 co-infected patients, 10 were positive for HCV RNA in semen and three were HIV/HCV RNA positive in semen.

CONCLUSIONS

Although HCV RNA was found in the semen of 11% of patients, no purified sperm fraction, or spermatozoa used in MAP were HCV RNA positive. The 90% purified sperm fraction discards the virus and must be used with care in MAP.

Sexually transmitted acute infection with a clustered genotype 4 hepatitis C virus in HIV-1-infected men and inefficacy of early antiviral therapy

BACKGROUND

Recent studies have suggested an increased risk of acute hepatitis C (HCV) infection in homosexual HIV-infected men and that early treatment with standard or pegylated interferon-alfa, alone or associated with ribavirin, significantly reduces the risk of chronic evolution in HIV-infected patients.

METHODS

A retrospective analysis of 12 HIV-infected patients who were consecutively diagnosed as developing acute HCV infection, defined by both seroconversion of anti-HCV antibodies and detection of serum HCV RNA in those with previous negative results. Ten of these patients received early antiviral treatment with standard or pegylated interferon-alfa, alone or associated with ribavirin.

RESULTS

The only risk factor in these patients was unprotected sexual intercourse with men. Acute HCV infection was asymptomatic in 10 patients, and the HCV genotype was 4d in 10 patients. The 10 genotype 4d viruses formed a monophylogenetic group and clustered separately from other local sequences of HCV genotype 4d, suggesting a common source of infection. None of the 10 patients who were treated early with antiviral therapy had a sustained virological response, as defined by undetectable HCV RNA 6 months after therapy.

CONCLUSIONS

There is a risk of sexual transmission of HCV in HIV-infected men who have sex with men; the cluster of HCV genotype 4d suggested a common source of infection and a failure in prevention counselling. Early treatment with standard interferon-alfa failed to prevent chronic evolution of HCV infection in this particular group of HIV-infected patients who had acquired this peculiar cluster of genotype 4 strains.

Molecular epidemiology of hepatitis C virus (HCV) in Greece: temporal trends in HCV genotype-specific incidence and molecular characterization of genotype 4 isolates

This study aimed to estimate the overall HCV genotype distribution and to reconstruct the HCV genotype-specific incidence in Greece during the recent decades. It also focused at the identification of genotype 4 subtype variability in Greek isolates. A total of 1686 chronically infected HCV patients with detectable serum HCV RNA by RT-PCR, belonging to different risk groups were studied. Amplified products from the 5'-noncoding region were typed using a commercially available assay based on the reverse hybridization principle. The HCV genotype-specific incidence was estimated using a previously described back calculation method. HCV genotype 1 was the most prevalent (46.9%) followed by genotype 3 (28.1%), 4 (13.2%), 2 (6.9%) and 5 (0.4%). A high prevalence of genotype 1 (66.3%) in haemophilia patients was recorded whereas HCV genotype 3 was found mainly among patients infected by I.V. drug use (58.2%). Data on the temporal patterns of HCV genotype-specific incidence in Greece revealed a moderate increase (1.3-1.6 times) for genotypes 1 and 4, and a decrease (1.5 times) for genotype 2 from 1970 to 1990, whereas there was a sharp (13-fold) increase for genotype 3. The molecular characterization of 41 genotype 4 HCV isolates belonging to various risk groups revealed that, subtype 4a was the most frequently detected (78%). Phylogenetic comparison of the Greek 4a isolates with all HCV-4a isolates reported worldwide so far revealed a topology which does not discriminate Greek isolates from the others. HCV-4 does not represent a recent introduction in Greece.

Hepatitis C virus in the semen of men coinfected with HIV-1: prevalence and origin

OBJECTIVE

To compare the prevalence of hepatitis C (HCV) RNA in semen from men infected with HCV and those coinfected with HIV-1/HCV and to study the origin of HCV shed in semen.

DESIGN

Two prospective studies (HC EP09 and BINECO) included 120 HCV-positive men, 82 coinfected with HIV-1; all had positive HCV RNA detection in blood.

METHODS

Paired blood and semen samples were collected for HCV RNA detection and quantification in seminal plasma and in blood serum; repeated semen samples were obtained for 45 men. HCV RNA was sought in spermatozoa and non-sperm cells. Phylogenetic analysis of the HVR-1 region of HCV compared the quasispecies in blood serum and seminal plasma of two men.

RESULTS

HCV RNA was more frequently found in the semen of men coinfected with HIV-1 (37.8%) than in those with only HCV infection (18.4%) (P = 0.033). HCV RNA detection in semen was intermittent and was positive in at least one semen sample of 42.8% of HIV-1/HCV-coinfected men who provided repeated samples. Men with HCV-positive semen had significantly higher HCV load in blood than men with HCV-negative semen (P = 0.038). Phylogenetic comparison of HCV quasispecies in blood and in semen showed no evidence of HCV replication in genital leukocytes; however, a phenetic structure was observed between compartments (P < 0.001).

CONCLUSIONS

HCV particles in semen originate from passive passage from blood, with preferential transfer of some variants. Nearly half of HIV-1/HCV-coinfected men may intermittently harbour HCV in their semen. Recommendations of protected sex for HIV-infected individuals should be reinforced.

[Sexual transmission of hepatitis C virus]

Hepatitis C virus (HCV) is usually transmitted parenterally, but sexual transmission is considered likely in the 20% of cases with no other risk factors. Retrospective cohort studies conducted among persons who have never injected drugs show that factors predictive of HCV seropositivity include the number of lifetime sexual partners, high-risk sexual practices, other sexually transmitted infections, and HIV seropositivity. Persons in long-term monogamous heterosexual relationships with a partner seropositive for HCV are at lower risk of HCV acquisition (0 to 0.6% peryear) than persons with multiple partners or those at risk for sexually transmitted diseases (0.4 to 1.8% per year). HCV RNA is detectable in genital fluids, but there is not yet any proof that the HCV RNA in genital secretions represents infectious virus. HCV can be transmitted by sexual intercourse but much less efficiently than other sexually transmitted viruses, such as HBV and HIV. Sexual transmission of HCV may be enhanced by other concomitant sexually transmitted infections with genital erosive lesions or via traumatic sexual intercourse with abrasion of the genital mucosa.

Presence of hepatitis C virus (HCV) RNA in the genital tracts of HCV/HIV-1-coinfected women

BACKGROUND

Hepatitis C virus (HCV)-infected women--in particular, those coinfected with human immunodeficiency virus type 1 (HIV-1)--can transmit infection to their children and sex partners.

METHODS

The present study was conducted to analyze the presence of HCV RNA in cervicovaginal lavage (CVL) fluid from 71 women (58 HCV/HIV-1-coinfected women and 13 HCV-infected, HIV-1-uninfected women) enrolled in the Women's Interagency HIV Study.

RESULTS

HCV RNA was detected (by a commercial polymerase chain reaction assay) in CVL fluid from 18 (29%) of the HIV-1-infected women and from none of the HIV-1-uninfected women (P<.05). Multivariate analysis revealed that risk factors for the presence of HCV RNA in CVL fluid were HCV viremia (odds ratio [OR], 16.81; P=.02) and HIV-1 RNA in CVL fluid (OR, 19.87; P=.02). This observation suggests local interactions between HIV-1 and HCV in the genital tract compartment. There was no correlation between HCV RNA in CVL fluid and CD4, CD8, or CD3 cell counts, HIV-1 RNA viremia, the number of leukocytes in CVL fluid, or HIV-1 therapy. Furthermore, in 3 of 5 analyzed patients who had a detectable CVL HCV RNA load, we found viral variants differing in the 5' untranslated region that were present neither in plasma nor in peripheral-blood mononuclear cells.

CONCLUSIONS

Our observations point to the importance of the genital tract compartment, in which local HCV replication could be facilitated by local HIV-1 replication.

A cluster of acute hepatitis C virus infection among men who have sex with men--results from contact tracing and public health implications

OBJECTIVE

An acute hepatitis C virus (HCV) infection in an HIV-positive man who had sex with men (MSM) was notified. In the period of his seroconversion he was also diagnosed with a rectal lymphogranuloma venereum (LGV) infection, and was part of a cluster of 15 LGV cases in 2003. Our aim was to investigate HCV transmission and to search for potential spread among sexual contacts and known LGV patients.

METHODS

Our case series included the index, two recent contacts, and 14 LGV cases. They were interviewed about parenteral exposure for HCV, history of sexually transmitted diseases(STDs), sexual behaviour and drug use. Laboratory investigations included anti-HCV antibodies, HCV-polymerase chain reaction, and HCV genotyping.

RESULTS

Seven out of 17 MSM recently seroconverted for HCV (41%). Three genotypes were found. Parenteral risk factors were excluded. Six out of seven had LGV proctitis coinciding with HCV seroconversion, six (86%) were HIV infected. Unprotected anal contact was practised by both HCV uninfected and infected cases. Unprotected active and passive fisting was reported by all seven HCV infected men, compared with two of nine uninfected men (P = 0.003). Non-intravenous drug use during sexual activities was common among all MSM. Numerous, often anonymous, sexual contacts in various European countries were reported.

CONCLUSIONS

A cluster of acute HCV infection is reported among mostly HIV-positive MSM, with multiple partners throughout Europe. Sexual techniques potentially leading to mucosal damage (fisting), concomitant STDs such as LGV and drug use seem facilitating factors for spread. Extensive case finding and partner tracing is advocated as well as targeted prevention messages.

Prevalence of hepatitis C infection in a population of asymptomatic people in a checkup unit in Mexico city

Hepatitis C virus (HCV) infection has an estimated prevalence of 3% around the world. Unfortunately, many persons with HCV infection are asymptomatic. The aim of this study was to determine the prevalence of hepatitis C Virus infection in asymptomatic persons. This study was carried out in a population-based cross-sectional study in the Checkup Unit of University Hospital in Mexico City. Patients with two or more HCV risk factors were studied. Serum specimens from all patients were screened for HCV RNA by qualitative polymerase chain reaction (PCR). HCV RNA-positive serum was also screened by quantitative PCR and for HCV genotype. Three hundred asymptomatic people were included, 194 men and 106 women, with a mean age of 46.8+/-11.9. Six (2%) of the 300 people were positive and viremic. The most common risk factors in positive patients were manicures or pedicures with a nonpersonal instrument and more than three sexual partners. We concluded that hepatitis C is frequent in asymptomatic people, and those people are often viremic. In addition, this study suggests that the spectrum of liver disease in asymptomatic and newly diagnosed HCV-positive persons is broad.

Lack of evidence of sexual transmission of hepatitis C virus in a prospective cohort study of men who have sex with men

OBJECTIVES

We studied the prevalence and incidence of hepatitis C virus (HCV) infection in the ongoing Omega Cohort Study of men who have sex with men (MSM).

METHODS

From January to September 2001, consenting men (n = 1085) attending a follow-up visit to the ongoing Omega Cohort Study were tested for HCV. If the test results were positive for HCV, we compared them with test results from previous serum samples collected from the time of entry into the original cohort study to determine the time of infection.

RESULTS

HCV prevalence at entry was 2.9% and was strongly associated with injection drug use (32.9% vs 0.3%, P<.0001). Only 1 seroconversion was identified in 2653 person-years of follow-up (incidence rate = 0.038 per 100 person-years). The seroconverter was an active injection drug user who reported needle sharing.

CONCLUSIONS

Sexual transmission of HCV among MSM appears to be rare.

Transmission risk of hepatitis C virus via semen during assisted reproduction: how real is it?

The risk of viral transmissibility in assisted reproduction is still a much-debated issue, especially for hepatitis C virus (HCV). HCV is a common causative agent for parenterally transmitted viral hepatitis. In addition, it has been incriminated in other routes of transmission, including sexual transmission and nosocomial infections. The management of infertility, in association with HCV, has sparked debates about the potential risk of spread of infection to virus-free individuals, embryos and/or semen. The lack of worldwide-accepted screening policies has helped to fuel this debate. Today, it is evident that there is a potential risk of spread of HCV through biological fluids, including semen, to other individuals. This risk can only be marginalized by the use of well-established criteria for safety in infertility centres, and by the use of proper initial detection and segregation of potentially hazardous materials. Techniques and protocols have been established to help the andrologist and embryologist to safeguard patients against such dangers, and should be imposed in all centres, allowing HCV-positive males to enter their assisted reproduction programmes.

[Sporadic transmission of hepatitis C in dental practice]

Percutaneous contact with contaminated blood is the principal mode of transmission of the hepatitis C virus (HCV). However, the diagnosis of infection in patients in whom no parenteral risk factor can be identified allows speculation on the existence of other routes of transmission. In the field of dentistry, the role of saliva has still not been defined as a potential vehicle for infection nor the role of dental treatment as a possible occult factor in the sporadic transmission of hepatitis C. HVC-RNA is detectable in the saliva of over 50% of patients with chronic hepatitis C. The infectivity of the HVC particles detected in the saliva has not been determined, though it may be deduced from epidemiological studies that their potential for transmission, if it exists, is extremely limited. There has been no documented case of HVC transmission in a dental clinic. Studies which propose a history of dental treatment as a risk factor for HVC infection have not achieved conclusive results. The age distribution of the prevalence of HVC could indicate that a risk of iatrogenic transmission existed in the past, before the systematic application of universal barriers. The transmission of HVC in dental clinics may be considered a very infrequent occurrence as long as the norms for the control of cross-infection are respected.

Acute hepatitis C in HIV-infected men who have sex with men

BACKGROUND

Hepatitis C virus (HCV) is usually transmitted via the parenteral route, but there are widely discrepant findings on its possible sexual transmission. Thus there are no recommendations concerning protected sex for couples in which only one partner is HCV-infected. Whether HIV or other sexually transmitted diseases could favour HCV transmission remains unclear, but recent data suggesting an increasing incidence of acute HCV in HIV-infected men underline the major public health implications of this issue.

CASE REPORTS

Between June 2002 and July 2003, five HIV-infected homosexually active men presented with primary (n=4) and secondary (n=1) syphilis and concomitant abnormal liver function tests revealing acute asymptomatic HCV seroconversion. Other causes of acute viral hepatitis were inquired into and excluded. Highly at-risk sexual behaviour, including unprotected anal intercourse and unsafe oral sex, with concomitant syphilis, was found to be the only identifiable important risk factor for transmission of HCV.

CONCLUSIONS

Sexual transmission may be fuelling a significant increase in HCV seroconversions among HIV-infected men who have highly risky sexual behaviours. Given the recent data suggesting the spread of sexually transmitted infections among HIV-infected gay men, specific recommendations concerning safe sex are urgently needed.

[Risk factors for hepatitis C virus infection]

INTRODUCTION

Hepatitis C viral infection represents a major health problem in the world. The estimated global incidence is about 3%, whereas the number of chronic hepatitis C virus (HCV) carriers worldwide is estimated to be between 150-300 million people.

MATERIAL AND METHODS

This retrospective analysis included 82 patients whose diagnosis of viral hepatitis C infection was based upon the following criteria: case history, physical examination, laboratory and abdominal ultrasound examination, histological examination of the liver, radiological examination, serological analysis and viral analysis. Descriptive statistics were used to describe general data on patients of the study group, risk factor analysis and follow-up results.

RESULTS

The most prominent risk factor in our study group was intravenous use of drugs in 37 patients (37%), and blood transfusion in 13 patients (13%). Less important risk factors of viral hepatitis C infection included: promiscuity (8%), sexual contact with hepatitis C carriers (5%), surgical intervention (5%), hemodialysis (3%), intranasal use of cocaine (2%).

DISCUSSION

Hepatitis C viral infection has become the illness of young and middle-aged population. This is due to the epidemic profile of this illness, due to intravenous use of drugs as the most prominent risk factor.

CONCLUSION

Due to the number of infected, numerous risk factors and complications of viral hepatitis C, hepatitis C virus has become the most prominent hepatotrophic virus.

Hepatite C: prevalência e fatores de risco entre portadores do VIH/SIDA em Belém, Pará, na Amazônia brasileira

Este trabalho objetivou investigar a prevalência de infecção pelo vírus da hepatite C e identificar possíveis fatores de risco para sua transmissão, em 406 indivíduos portadores do vírus da imunodeficiência humana, maiores de dezoito anos de idade, atendidos na rede pública de saúde da cidade de Belém, Pará, situada na Amazônia brasileira. Os exames referentes ao anti-VHC foram realizados pelo método de Elisa e a pesquisa do VHC RNA através da reação de polimerase em cadeia. A prevalência de infecção, atual ou pregressa, pelo vírus da hepatite C foi de 16% (IC: 12,4 - 19,6). A análise multivariada mostrou associação do vírus C com as variáveis idade, cujo risco significante recaiu no grupo com cinqüenta ou mais anos (OR=9,75), antecedente de transfusão de sangue (OR=4,74) e uso de droga ilícita injetável (OR=149,28). A prevalência do vírus da hepatite C entre os usuários de drogas injetáveis foi de 83,7% e de 22,1% na população de transfundidos. Estes resultados indicam a efetiva transmissão do vírus C através da exposição percutânea e reafirmam o grande potencial de risco para hepatite C contido no uso injetável de drogas ilícitas.

Molecular investigation of interspousal transmission of hepatitis C virus in two Japanese patients who acquired acute hepatitis C after 40 or 42 years of marriage

A 65-year-old woman (C1I) and a 65-year-old man (C2I) contracted acute hepatitis C 40 or 42 years after marriage, respectively, in Japan. They had no discernible risk factors for acquiring hepatitis C virus (HCV) infection, except that they had monogamous sexual relationships with their spouses (C1S [66-year-old] with hepatocellular carcinoma and C2S [64-year-old] with liver cirrhosis, respectively) who were infected with HCV of the same genotype (1b) and had a high-titer HCV RNA in the serum (bDNA probe assay, 17 Meq/ml [C1S] and 15 Meq/ml [C2S]). The HCV isolates from Patients C1I and C1S and those from Patients C2I and C2S shared identity of 99.9% and 99.1%, respectively, in the 1,087-nucleotide (nt) sequence of the NS5B region, although these four isolates were only 91.7%-96.2% identical to the 94 reported genotype 1b isolates including those from Japanese patients. To confirm the high degree of genetic relatedness among ten HCV clones from each spouse within each pair of spouses, the E1 and E2 junctional region sequence (268 or 271 nt) including hypervariable region 1 (HVR-1) was analyzed. There was a close relationship between clones obtained from each spouse within each couple. Regarding the HVR-1 amino acid sequence, nine of the ten C1I clones were 100% identical with six of the ten C1S clones, and one each of the C2I and C2S clones differed by only one amino acid residue. This study indicates that two Japanese patients with acute hepatitis C had acquired HCV infection most probably by interspousal sexual transmission during a long-lasting marriage.

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.

Association of hepatitis C virus infection with sexual exposure in southern India

To determine the association between sexual exposure and hepatitis C virus (HCV) infection in urban Chennai, India, a random sample of adults who live in a slum community completed interviews and provided samples to test for HCV, herpes simplex virus type 2 (HSV-2), and other sexually transmitted infections (STIs). All analyses excluded recent and current injection drug users. HCV infection was not associated with the reported number of sex partners for men or women. Women were more likely to be HCV infected if they reported previous genital ulcer disease (adjusted odds ratio [AOR], 3.88; 95% confidence interval [95% CI], 0.94-16.0; marginally statistically significant). Men were more likely to be HCV infected if they were HSV-2 infected (AOR, 3.85; 95% CI, 1.18-12.6) or reported having had sex with men (AOR, 3.61; 95% CI, 1.00-13.1). Sexual transmission of HCV infection may be facilitated by ulcerative STIs and male-male sexual practices, but it appears to occur infrequently in this population.

Sexual transmission of hepatitis C virus from a patient with chronic disease to his sex partner after removal of an intrauterine device

BACKGROUND

Approximately 40% of patients infected with hepatitis C virus (HCV) have no history of blood transfusion or other high-risk practice. Other causes should be considered.

GOAL

The goal was to describe sexual transmission of HCV from a chronic carrier to his female partner during unprotected vaginal intercourse after removal of an intrauterine device.

STUDY DESIGN

A heterosexual woman who was a regular blood donor acquired acute HCV infection from her sex partner, who was chronically infected. The study included an interview and phylogenetic analysis of sequences of virus obtained from the couple.

RESULTS

Risk factors other than vaginal sexual relations with her partner were ruled out. Phylogenetic analysis showed that sequences from the couple clustered together in all trees generated, in comparison with local and GenBank controls.

CONCLUSION

The temporal relationship between removal of the intrauterine device and the acute hepatitis suggests that vaginal mucosal damage might have favored transmission of HCV. Barrier precautions should be suggested whenever damage of the vaginal tract has occurred.

Intermittent detection of hepatitis C virus (HCV) in semen from men with human immunodeficiency virus type 1 (HIV-1) and HCV

HCV is usually transmitted via the blood, but HCV RNA has been detected recently in seminal fluid. This study was done to study HCV seminal shedding and factors that could influence the presence of HCV in the seminal fluid of men coinfected with HCV and HIV-1. HCV and HIV-1 genomes were assayed in multiple paired blood and semen samples obtained from 35 men enrolled in an assisted medical procreation protocol. HCV RNA was found intermittently in semen samples from 9 patients (25.7%). Samples from 9 men with HCV RNA in their semen and 26 men without were compared to further analyze these parameters. No correlation was found between HCV RNA in the seminal fluid and age, HCV virus load, the duration of HIV-1 infection, HIV treatment, the CD4(+) cell count, HIV-1 virus load or HIV-1 detection in the semen. The intermittent detection of HCV RNA in semen samples support the systematic search for HCV RNA in semen and the use of processed spermatozoa in assisted medical procreation of infertile HCV serodiscordant couples.

Multicenter quality control for the detection of hepatitis C virus RNA in seminal plasma specimens

The discrepant results available in the literature about the presence of hepatitis C virus (HCV) RNA in seminal plasma of men chronically infected by this agent are related, at least in part, to the molecular techniques used and particularly to the wide range of protocols dedicated to RNA extraction. In order to evaluate these protocols and to standardize the method of detection of HCV RNA in this fluid, a panel of coded specimens was tested blindly in 12 French laboratories; it included 14 seminal plasma specimens and four water controls spiked with HCV RNA ranging from 10 to 20000 IU/ml and two HCV-negative seminal plasma specimens. The extraction step was performed according to methods using either silica beads (NucliSens [Organon Teknika S.A., Fresnes, France]; RNA viral kit [Qiagen, Courtaboeuf, France]) or guanidinium thiocyanate (Amplicor HCV assay; Roche Diagnostics, Meylan, France), preceded or not by a centrifugation of the seminal plasma. For the amplification step, all the laboratories performed the same reverse transcription-PCR technique (Amplicor HCV Cobas assay). The percentage of correct results ranged from 53.3 to 100, the poorest results being obtained when no centrifugation step preceded the Amplicor extraction protocol. The rate of correct results was significantly higher in laboratories using a preliminary centrifugation of the specimen (P = 0.034 by chi-square test). By contrast, the overall number of correct results was not correlated to the initial volume of sample used for the test. These results allowed us to validate standardized techniques adapted to the performance of this test on a routine basis, especially in men infected with HCV and involved in programs of medically assisted reproduction.

Sexual activity as a risk factor for hepatitis C

The accumulated evidence indicates that hepatitis C virus (HCV) can be transmitted by sexual contact but much less efficiently than other sexually transmitted viruses, including hepatitis B virus and human immunodeficiency virus (HIV). However, because sex is such a common behavior and the reservoir of HCV-infected individuals is sizable, sexual transmission of HCV likely contributes to the total burden of infection in the United States. Risk of HCV transmission by sexual contact differs by the type of sexual relationship. Persons in long-term monogamous partnerships are at lower risk of HCV acquisition (0% to 0.6% per year) than persons with multiple partners or those at risk for sexually transmitted diseases (0.4% to 1.8% per year). This difference may reflect differences in sexual risk behaviors or differences in rates of exposure to nonsexual sources of HCV, such as injection drug use or shared razors and toothbrushes. In seroprevalence studies in monogamous, heterosexual partners of HCV-infected, HIV-negative persons, the frequency of antibody-positive and genotype-concordant couples is 2.8% to 11% in Southeast Asia, 0% to 6.3% in Northern Europe, and 2.7% in the United States. Among individuals at risk for sexually transmitted diseases (STDs), the median seroprevalence of antibody to HCV (anti-HCV) is 4% (range, 1.6% to 25.5%). HIV coinfection appears to increase the rate of HCV transmission by sexual contact. Current recommendations about sexual practices are different for persons with chronic HCV infection who are in steady monogamous partnerships versus those with multiple partners or who are in short-term sexual relationships.

Sexual activity as a risk factor for hepatitis C

The accumulated evidence indicates that hepatitis C virus (HCV) can be transmitted by sexual contact but much less efficiently than other sexually transmitted viruses, including hepatitis B virus and human immunodeficiency virus (HIV). However, because sex is such a common behavior and the reservoir of HCV-infected individuals is sizable, sexual transmission of HCV likely contributes to the total burden of infection in the United States. Risk of HCV transmission by sexual contact differs by the type of sexual relationship. Persons in long-term monogamous partnerships are at lower risk of HCV acquisition (0% to 0.6% per year) than persons with multiple partners or those at risk for sexually transmitted diseases (0.4% to 1.8% per year). This difference may reflect differences in sexual risk behaviors or differences in rates of exposure to nonsexual sources of HCV, such as injection drug use or shared razors and toothbrushes. In seroprevalence studies in monogamous, heterosexual partners of HCV-infected, HIV-negative persons, the frequency of antibody-positive and genotype-concordant couples is 2.8% to 11% in Southeast Asia, 0% to 6.3% in Northern Europe, and 2.7% in the United States. Among individuals at risk for sexually transmitted diseases (STDs), the median seroprevalence of antibody to HCV (anti-HCV) is 4% (range, 1.6% to 25.5%). HIV coinfection appears to increase the rate of HCV transmission by sexual contact. Current recommendations about sexual practices are different for persons with chronic HCV infection who are in steady monogamous partnerships versus those with multiple partners or who are in short-term sexual relationships.