Donor Hepatitis C Virus Research Articles

HCV in Patients With End-Stage Renal Disease

Chronic hepatitis C virus (HCV) infection remains an important cause of liver disease in patients with end-stage renal disease (ESRD) and conversely, renal failure has a significant impact on morbidity and mortality throughout the natural history of chronic HCV and its treatment. With improved awareness within dialysis units of the potential for spread and the institution of preventative measures, the prevalence of HCV infection in the hemodialysis-dependent population has continued to decline since 1995. Use of HCV (+) donor kidneys is associated with an increase in the prevalence of liver disease, but when compared with continued hemodialysis, transplantation using these kidneys is associated with improved survival. Overall, survival in patients with chronic HCV infection appears to be better after renal transplantation when compared with maintenance hemodialysis, and transplant should be considered for these patients. Data support the use of interferon and the improved efficacy of pegylated interferon formulations for treatment of chronic HCV infection in ESRD patients, although tolerability continues to be troublesome. The newest and most promising data regarding the treatment of HCV in ESRD involve the combination of reduced dose ribavirin with interferon or pegylated interferon suggesting similar enhancements in sustained virologic response (SVR) as seen in non-ESRD patients, but caution is advised, as all studies to date used ribavirin plasma concentration monitoring in patient with ESRD. Finally, with regard to postrenal transplant treatment of HCV infection, there is no evidence to support treatment with interferon-based therapy and pretransplant treatment remains the best option whenever possible.

Immunostimulatory effects of three classes of CpG oligodeoxynucleotides on PBMC from HCV chronic carriers

BackgroundChronic hepatitis C virus (HCV) infection results from weak or absent T cell responses. Pegylated-interferon-alpha (IFN-α) and ribavirin, the standard of care for chronic HCV, have numerous immune effects but are not potent T cell activators. A potent immune activator such as TLR9 agonist CpG oligodeoxynucleotide (CpG) may complement current treatment approaches.MethodsPeripheral blood mononuclear cells (PBMC) obtained from HCV chronic carriers who failed previous treatment and from healthy donors were incubated in vitro with the three main CpG classes (A, B or C), recombinant IFN-α-2b (IntronA) and/or ribavirin. Proliferation and cytokine secretion (IFN-α, IL-10 and IP-10) were evaluated.ResultsCpG induced proliferation and cytokine secretion in patterns expected for each CpG class with similar group means for HCV and healthy donors. IntronA and ribavirin, alone or together, had no detectable effects. IntronA and C-Class CpG together induced more IFN-α than CpG alone in most subjects. IFN-α secretion was proportional to the number of plasmacytoid dendritic cells in PBMC from healthy donors but not HCV donors in whom responses were highly heterogeneous.ConclusionThe strong immune stimulatory effect of CpG on PBMC isolated from treatment-failed HCV patients suggests possible utility alone or in combination with current HCV antiviral treatment.

Hepatitis C Virus-Infected Donors in Liver Transplantation

Preliminary findings suggest that hepatitis C virus (HCV)-infected liver transplant recipients receiving livers from HCV-infected donors may have a slower rate of fibrosis progression at 1 year. According to a case-control study presented May 20, 2007 at Digestive Disease Week 2007 in Washington, DC, a trend was seen in survival advantage for those receiving HCV-positive donor grafts compared with standard donor controls. “The use of HCV positive donors may be considered as a first line therapy to increase the available donor pool of organs in those undergoing orthoptic liver transplantation for HCV-related cirrhosis,” say researchers led by Paul Y. Kwo, Associate Professor of Medicine in the Division of Digestive Diseases at Indiana University School of Medicine in Indianapolis. This study utilized a case-control design to compare transplant outcomes for 38 recipients of livers from HCV-infected donors with those for 76 standard, nonextended criteria (ECD) donors (1 case/2 controls). Data were extracted from the transplant center registry, UNOS data, and the original on-site donor data chart. Thirty percent of all donors met non-ECD criteria (standard donors) and were included as potential matches for the case-control study. Each HCV-positive liver donor recipient was matched with 2 standard donor recipients as matched standard donor controls (MSDC) by (1) recipient age ± 10 years; (2) primary diagnosis; (3) cancer stage for those with hepatocellular carcinoma; (4) recipient Model for End-Stage Liver Disease score ± 5; and (5) donor age ± 10 years. Outcomes included graft and patient survival at 3 months, 1 year, and 2 years; perioperative death; and HCV recurrence by 4-month and 1-year fibrosis (F0–F4). The HCV donor and MSDC groups did not differ for recipient or donor demographics or in cold and warm ischemia times. Survival results and fibrosis progression are shown in Table 1. Median follow-up time was 36 months. Kaplan–Meier actuarial survival demonstrated improved graft survival for HCV-infected donors with a trend toward significance (P = .10).Tabled 1Hepatitis C-infected donorMatched standard donor controls (MSDC)n-value*TOTALn = 38n = 7690-day survival Graft37/38 (97.4%)72/76 (94.7%)NS Patient37/38 (97.4%)72/76 (94.7%)NS1-year survival Graft30/31 (96.8%)62/72 (86.1%)NS Patient31/31 (96.8%)63/72 (87.5%)NS2-year survival Graft16/19 (84.2%)49/62 (79.0%)NS Patient17/19 (84.2%)52/62 (83.9%)NSGraft loss within 7 days1/38 (2.6%)1/76 (1.3%)NSMean fibrosis at 4 months (F0–F4)0.680.330.08Mean fibrosis at 12 months (F0–F4).0861.05NSPercent change in fibrosis26%69% Open table in a new tab

Mild donor liver steatosis has no impact on hepatitis C virus fibrosis progression following liver transplantation

This study examines the impact of donor liver macrovesicular steatosis on recurrence of hepatitis C virus (HCV) disease after liver transplantation. Between 1998 and 2004, 113 patients underwent liver transplantation for HCV-related cirrhosis. Time to histologic recurrence (fibrosis score >or=2) was the primary endpoint of the study. Recurrence was graded according to the system of Ludwig and Batts. A Cox's proportional hazard regression model was used to analyse the association between donor liver steatosis and HCV recurrence. Recurrence-free survival for patients who received steatotic grafts was 82% and 47% at 1 and 4 years, respectively, and 81% and 52% for patients who received a non-steatotic liver. Donor macrovesicular steatosis (5-45%) was found to have no impact on HCV recurrence (P=0.47). Donor age (P=0.02) and cold ischaemia time (P=0.01) were found to increase the relative risk of HCV recurrence. The estimated risk of HCV recurrence increased by 23% for every 10-year increase in donor age. Similarly the risk of recurrence increased by 13% for every 1-h increase in cold ischaemia time. Mild-moderate donor liver macrovesicular steatosis has no impact on HCV recurrence after liver transplantation for HCV-related cirrhosis. Cold ischaemia time and donor age increased the likelihood of HCV recurrence.

Hepatitis C Virus Seropositivity in Organ Donors and Survival in Heart Transplant Recipients

Although liberalization of donor criteria could expand the donor pool, the use of certain "marginal donors," such as those who are hepatitis C virus (HCV) positive, is controversial. Little is known about the effect of donor HCV positivity on survival in cardiac transplantation. To examine the association between donor HCV positivity and survival among heart transplant recipients and to determine the effects of recipient age and recipient HCV status on this association. A multicenter cohort study was performed using the US Scientific Registry of Transplant Recipients. Adult heart transplant patients who received their transplants between April 1, 1994, and July 31, 2003, were eligible for inclusion. All-cause mortality. Of 10 915 patients meeting entry criteria, 261 received an HCV-positive donor heart. Mortality was higher among recipients of HCV-positive donor hearts at 1 year (16.9% vs 8.2%; P<.001), 5 years (41.8% vs 18.5%; P<.001), and 10 years (50.6% vs 24.3%; P<.001). Using Kaplan-Meier methods, 1-, 5-, and 10-year survival rates were 83%, 53%, and 25%, and 92%, 77%, and 53% for recipients of HCV-positive and HCV-negative donor hearts, respectively (P<.001, log-rank test). Recipients of HCV-positive donor hearts were more likely to die of liver disease and coronary vasculopathy. After propensity matching, the overall hazard ratio (HR) associated with receipt of an HCV-positive donor heart was 2.10 (95% confidence interval [CI], 1.60-2.75). Stratified analyses showed that HRs did not vary by recipient HCV status or by recipient age (for recipients aged 18-39 years: HR, 1.75 [95% CI, 0.70-4.40]; for recipients aged 40-59 years: HR, 2.23 [95% CI, 1.42-3.52]; and for recipients aged 60 years and older: HR, 2.07 [95% CI, 1.32-3.27]; overall P value for interaction, >.10). Receipt of a heart from an HCV-positive donor is associated with decreased survival in heart transplant recipients. This association appears to be independent of recipient HCV status and age. Preferential allocation of HCV-positive donors to HCV-positive recipients and/or older recipients is not warranted.

Performance of ORTHO® HCV core antigen and trak‐C™ assays for detection of viraemia in pre‐seroconversion plasma and whole blood donors

Logistics and cost of nucleic acid amplification testing (NAT) screening preclude its current use in many developing countries. Development of hepatitis C virus (HCV) core antigen assays offer an alternative to NAT. We evaluated two specimen populations to assess the sensitivity, relative to NAT, of the HCV core antigen (HCVcAg) ELISA (enzyme-linked immunosorbent assay) test system and the trak-C assay: (1) plasma donor HCV NAT-conversion panels and (2) cross-sectional whole blood donor NAT yield specimens. Differential sensitivities among NAT (NGI; Chiron/Gen-Probe) and both HCVcAg assays (Ortho-Clinical Diagnostics, Rochester, NY) were evaluated using: (1) 102 serial ramp-up phase specimens from 37 plasma donor NAT-conversion panels (Alpha Therapeutic/BioClinical Partners); and (2) 42 cross-sectional whole blood donor NAT yield specimens (confirmed RNA positive, antibody negative) plus 54 NAT false-positive specimens (American Red Cross). Viral load among the plasma donor NAT-conversion panels at the cutoffs for HCVcAg and trak-C assays were 32 000 copies/ml (95% confidence interval [CI] 8000-120 000) and 8000 copies/ml (95% CI: 2200-28 000), respectively. The mean (95% CI) difference in window period reduction compared to routine mini-pool NAT screening (estimated sensitivity 100 copies/ml) was delayed 5.2 days (2.2-7.6 days) for HCVcAg assay and 3.8 days (2.1-5.5 days) for the trak-C assay. Among the 42 NAT yield specimens, the HCVcAg assay detected 31 (74%) as core antigen-positive while the trak-C assay detected 37 (88%) as core antigen-positive. Viral loads for the five specimens not detected by the trak-C HCVcAg assay ranged from 100 to 7770 copies/ml. All 54 NAT false-positive specimens were non-reactive on both HCV core antigen assays. These data indicate that the trak-C assay has sensitivity approaching routine mini-pool NAT screening for the detection of seronegative HCV infection. In the absence of routine NAT screening for early HCV infection, the use of an HCV core antigen assay should be considered.

Treatment of Recurrent Hepatitis C in Liver Transplant Recipients

The course of hepatitis C is accelerated after transplantation, with an average of 25% of patients developing cirrhosis within 5 years of transplantation. Consequently, the 5- and 10-year graft survival rates in hepatitis C virus (HCV)-infected patients are significantly lower than in HCV-uninfected patients. Therapeutic interventions to prevent HCV recurrence and/or alter the rate of disease progression after transplantation are desirable. Prophylactic therapy in the form of polyclonal HCV antibodies has not been effective at prevention of HCV re-infection, but one study suggests that higher-dose therapy may modify the severity of early disease recurrence. Pre-emptive antiviral therapy has modest efficacy and generally is poorly tolerated. Live donor liver transplant recipients and recipients with low model of end-stage liver disease scores pretransplantation may tolerate pre-emptive therapy best. The treatment of recurrent established disease with a combination of interferon and ribavirin has been the mainstay of management. Similar to pre-emptive therapy, tolerance is reduced and dose reductions are frequent. The sustained virologic response rates are less than 45% in studies to date. Histologic and biochemical improvements generally are more frequent than virologic responses. Overall, the treatment of HCV disease in transplant recipients leaves much to be desired and there is an urgent need of new HCV therapies in this patient population.

Serum Alanine Aminotransferase may not be a good surrogate marker of Hepatitis C Virus infection: A Study of Blood Donors in University of Maiduguri Teaching Hospital (UMTH), Maiduguri, Nigeria

Background: Prior to the identification of Hepatitis C virus (HCV) in 1989, raised serum alanine aminotransferase (ALT) was used as a surrogate marker for non-A, non-B (NANB) hepatitis agents to reduce the risk of post-transfusion hepatitis. Most of this NANB hepatitis was later found to be due to HCV infection. The absence of a national screening policy for HCV infection and the non-availability of screening facilities in most of our health institution may place many blood recipients at risk of HCV infection. Aim: This study was set to evaluate the usefulness of serum ALT as a surrogate marker of HCV infection in blood donors. Methodology: The study was conducted at the University of Maiduguri Teaching Hospital between August 2002 to November 2002. Ninety-six healthy, volunteer, blood donors were screened for anti-HCV using a third-generation ELISA test kits, and all had serum ALT levels measured. Result: Antibodies against HCV was detected in 10.4% of donors and the overall mean serum ALT level was 8.84 (±5.6) iu/L. The mean serum ALT level for anti-HCV positive and negative was 7.7 (±2.45) and 8.9 (±5.86) iu/L, respectively, of which, there was no statistically significant difference between the two groups. Conclusion: While the prevalence of antibodies against HCV in blood donors appears to be high in north-eastern Nigeria, serum ALT levels may not be a good surrogate marker for HCV infection in blood donors in this environment. Key Words: Blood donors, HCV, Serum ALT levels. Sahel Medical Journal Vol.7(3) 2004: 88-91

Transmission in vitro of hepatitis C virus from persistently infected human B-cells to hepatoma cells by cell-to-cell contact

Virus cell-to-cell spread has been reported for many different viruses and may contribute to pathogenesis of viral disease. The role played by cell-to-cell contact in hepatitis C virus (HCV) transmission was studied in vitro by cell co-cultivation experiments. A human lymphoblastoid B-cell line, infected persistently with HCV in vitro (TO.FE(HCV)), was used as HCV donor [Serafino et al., 2003]; recipient cells were the human hepatoma HepG2 cell line. Both cell types were co-cultured for 48 hr to allow the cell-to-cell contacts. The hepatoma HepG2 cells are not permissive to free-virus infection, but they were infected successfully using TO.FE(HCV) cells as source of virus. The kinetics of viral RNA synthesis and the percentage of infected cells were compared in cell-mediated-and cell-free-viral infection. After co-cultivation, a consistent proportion of hepatoma cells replicated HCV and stably expressed viral antigens. Virus produced was infectious as demonstrated by the ability to reinfect fresh B-cells. This cell model shows that permissiveness to HCV infection can be achieved in vitro in non-permissive hepatoma cells by direct cell-to-cell contacts with infected human B-cells. This mechanism of virus spread may also play a pathogenic role in vivo.

Hepatitis C virus infection in asymptomatic male volunteer blood donors in Karachi, Pakistan

The objectives of this study were to assess the proportion of hepatitis C virus (HCV) reactors and to identify risk factors associated with HCV infection in volunteer blood donors in Karachi, Pakistan. Between 1 January 1998 and 31 December 2002, consecutive blood donations tested at two blood banks were used to assess the proportion of HCV sero-reactors donors. To evaluate the potential risk factors, a case-control study design was implemented to select cases and controls between 15 October 2001 and 15 March 2002. The overall seroprevalence of HCV in these blood donors was 1.8% (6349/35 1309). Trend analysis revealed a significant (P < 0.001) linear increase in proportions of HCV-seropositive donors from 1998 to 2002. Final multivariate logistic regression model showed that the cases were more likely than controls to have reported past hospitalization or to have received multiple injections. When a glass syringe was used to give therapeutic injections, it increased the adjusted odds of being HCV seropositive significantly more among cases than in controls and this relationship was stronger when injection was given by general medical practitioner than if the injection was given in hospital setting. Cases were more likely than controls to have reported sexual contact with multiple sexual partners. Primary prevention programmes focused on identified risk factors might help to curtail the spread of HCV infection in this community and in other similar settings in developing countries.

Seroprevalence of common transfusion-transmitted infections among blood donors in Bangladesh

Transfusion-transmitted infections (TTIs) remain a major global public health problem and a challenge to transfusion services worldwide particularly in developing countries in managing transfusion-dependent children especially the thalassaemics. However developed countries are not exempt from TTIs despite multiple layers of protection in their advanced blood collection centres. The magnitude of this problem is directly related to the prevalence of TTIs among blood donors. To assess the global burden of TTIs the World Health Organization (WHO) estimated that 3% of the world’s population (.170 million people) are infected with hepatitis C virus (HCV). The global prevalence of HCV reported by the WHO ranges from 10 to 15% to as little as 0.04%. HCV in blood donors varies from 0.4 to 19% including 0.9% among Namibian first-time blood donors. The overall prevalence of HCV in Bangladesh as documented in the WHO’s records ranges between 1 and 2.5% whereas it was observed in 2.4% of professional donors (poor people who sell their own blood to make a living and who have had no evident disease) in Bangladesh. However in voluntary donors (healthy adults who only donate blood in emergencies) in India the prevalence of HCV ranged from 0.8 to 1.78%. In Japan and Germany figures of 0.6% and 0.2–0.8% respectively have been reported. (excerpt)

Liver transplantation with hepatitis C virus-infected graft: Interaction between donor and recipient viral strains

Superinfection of different viral strains within a single host provides an opportunity for studying host-virus and virus-virus interactions, including viral interference and genetic recombination, which cannot be studied in infections with single viral strains. Hepatitis C virus (HCV) is a positive single-strand RNA virus that establishes persistent infection in as many as 85% of infected individuals. However, there are few reports regarding coinfection or superinfection of HCV. Because of the lack of tissue culture systems and small animal models supporting efficient HCV replication, we explored these issues in the setting of liver transplantation where both recipient and donor were infected with different HCV strains and therefore represent a distinct model for HCV superinfection. Serial serum samples collected at multiple time points were obtained from 6 HCV-positive liver donor/recipient pairs from the National Institute of Diabetes and Digestive and Kidney Diseases liver transplantation database. At each time point, HCV genotype was determined by both restriction fragment length polymorphism analysis and phylogenetic analysis. Furthermore, we selectively sequenced 3 full-length HCV isolates at the earliest time points after liver transplantation, including both 5′ and 3′ ends. Detailed genetic analyses showed that only one strain of HCV could be identified at each time point in all 6 cases. Recipient HCV strains took over in 3 cases, whereas donor HCV strains dominated after liver transplantation in the remaining 3 cases. In conclusion, in all 6 cases studied, there was no genetic recombination detected among HCV quasispecies or between donor and recipient HCV strains. (H epatology 2003;38:25-33.)

Estimation of the risk of hepatitis B virus, hepatitis C virus and human immunodeficiency virus infectious donations entering the blood supply in England, 1993-2001.

The frequency of hepatitis B virus (HBV), hepatitis C virus (HCV) or human immunodeficiency virus (HIV) infectious donations entering the blood supply in England is too low to monitor using observational studies. The expected frequency of infectious donations can be estimated and these estimates may be used to contribute to monitoring of blood safety and used in the design of strategies to decrease the risk of transfusion-transmitted infections. The prevalence and incidence of hepatitis B surface antigen (HBsAg), and antibodies to HCV and HIV (anti-HCV and anti-HIV, respectively) in donors in England, between 1993 and 2001, were used together with data about the length of negative 'window-periods' of current assays for each of these markers and data about test performance, to estimate the number of infectious donations that enter the blood supply. The risks were calculated separately for donations from new donors and from repeat donors, and for the three time periods 1993-95, 1996-98 and 1999-01. The estimated frequency of infectious donations entering the blood supply in England, between 1993 and 2001 was 1 in 260,000 for HBV and 1 in 8 million for HIV. For HCV, the frequency of infectious donations was 1 in 520,000 during 1993-98 and fell to 1 in 30 million during 1999-2001 when all donations were tested for HCV RNA. The frequency of HBV- and HCV-infectious donations entering the blood supply fell over these 9 years: the frequency of HIV-infectious donations remained essentially unchanged. The risk from donations from new donors was found to be approximately sevenfold higher than the risk from donations from repeat donors. The risks of HBV-, HCV- or HIV-infectious donations entering the blood supply in England are very low, and have decreased since 1993. Although the accuracy of these estimates is imperfect, mainly owing to uncertainty in some assumptions and to small numbers of infections, they provide some quantification of the risk of HBV, HCV or HIV transmission by transfusion, and allow comparison of the magnitude of these risks for each infection and over time. The methods we have used have been developed and improved from previously published methods.

The outcome of liver grafts procured from hepatitis C-positive donors.

The growing prevalence of hepatitis C virus (HCV) infection in the general population has resulted in an increased frequency of potential organ donors that carry the virus. The survival of grafts from HCV+ donors has not been studied in detail. Two study populations were examined retrospectively to assess the survival of liver grafts procured from HCV+ donors. First, we evaluated the survival of all 13 HCV+ and 103 HCV- grafts that were transplanted at our institution to HCV+ recipients from January 1, 1995 to December 31, 1999. In parallel, we analyzed a subset of the United Network for Organ Sharing (UNOS) liver transplant database from the same 5-year time period that was comprised of 14,195 adult patients for whom donor and recipient HCV serologies were known. Kaplan-Meier graft survival for both patient populations was calculated based on donor and recipient HCV serologic status. A Cox proportional hazards analysis was performed on UNOS data to identify variables independently predicting graft survival. For transplants performed at our institution, we found no statistically significant difference in the Kaplan-Meier graft survival of HCV+ and HCV- grafts transplanted to HCV+ recipients (P=0.68). The incidence of biopsy-proven, recurrent HCV posttransplant was similar in recipients receiving either HCV+ or HCV- grafts (4/13 vs. 18/103, chi-square P=0.211). Analysis of UNOS data revealed that the survival of HCV+ grafts in HCV+ recipients was equivalent to the survival of HCV- grafts in HCV+ recipients. Unexpectedly, the survival of grafts in HCV+ recipients in general was significantly inferior to that of grafts in HCV- recipients. Multivariate analysis of all patients found recipient but not donor HCV status to be independently predictive of graft survival. Analysis of data from a single center and the national UNOS database suggests that transplantation of liver allografts from HCV+ donors to HCV+ recipients results in graft survival comparable to HCV- grafts transplanted to HCV+ recipients. In contrast, recipient HCV positivity is an independent predictor of graft failure compared with patients transplanted for other causes of liver disease.

DONOR HEPATITIS C VIRUS STATUS DOES NOT ADVERSELY AFFECT SHORT-TERM OUTCOMES IN HCV+ RECIPIENTS IN RENAL TRANSPLANTATION1

Recipient hepatitis C virus (HCV) seropositivity has been associated with inferior outcomes in renal transplantation (RTx). We sought to determine whether donor HCV+ status influenced the incidence of rejection, liver dysfunction, and graft survival in HCV+ recipients. We reviewed 44 HCV+ recipients (R+) receiving RTx from HCV+ (D+) and HCV- (D-) donors between February 1991 and September 1996. All patients were followed to the end of the study period (mean=36 months, range=12-60 months). We compared the R+ group with a demographically matched cohort of 44 HCV- recipients (R-). Of the 44 R+, 25 (57%) had a total of 48 rejection episodes. Among the 44 R-, 32 (73%) had 58 rejection episodes (P>0.1). Within the R+ group, 28 were D+/R+; of these 14 (50%) had 27 rejection episodes, whereas among the 16 D-/R+, 11 (68%) had 21 rejection episodes (P>0.3). Graft and patient survival was similar in both the groups (86.4% and 91%, respectively). Liver dysfunction was slightly increased in the R+ group (4/44 vs. 0/44, P>0.1), with one death due to liver failure in this group. Donor HCV+ status had no influence on outcomes in HCV+ recipients after kidney transplantation in the short term. The incidence of rejection, graft loss, and mortality was comparable between the D+/R+ and D-/R+ groups. Furthermore, rejection, graft loss, and death were identical in R+ and R-groups throughout the 5-year study period. We therefore conclude that HCV+ recipients can safely receive kidney transplants without concern about donor HCV status or fear of adverse events from their own HCV+ status.

High prevalence of hepatitis C infection among blood donors in northeastern Thailand.

Previous studies on the prevalence of hepatitis C virus (HCV) infection in Asian countries reported an average prevalence of less than 1.5%. In this study a combination of second- and third-generation enzyme immunoassays (EIAs), immunoblot analysis, and polymerase chain reaction was used to evaluate the prevalence of HCV infection in 3,255 volunteer blood donors in northeastern Thailand. Antibodies to HCV were detected in 6.5% of male blood donors and 0.9% of female blood donors, giving an overall prevalence of 5.6% in this population (gender-adjusted prevalence of 3.7%). The prevalence was higher in males than in females (P < 0.0001) and increased with age, reaching a peak at 31-40 years of age. More than 90% of the EIA-positive samples tested positive by immunoblot analysis, giving an estimated minimal prevalence of antibodies to HCV in the blood donors of 5.2%. Approximately 80% of the EIA-positive blood donors were viremic as determined by the presence of HCV RNA detected by the polymerase chain reaction, indicating that at least 4.5% of volunteer blood donors had detectable HCV RNA and were considered potentially infectious. The prevalence of HCV infection in this population was higher than that in previous reports for central and northern Thailand, while the prevalence of HBV infection was similar to that in other regions of the country. This study clearly demonstrated a very high prevalence of HCV infection in northeastern Thailand, especially in the male population.

The risk of transmitting HCV, HBV or HIV by blood transfusion in Victoria.

To report the incidence rate of hepatitis B virus (HBV), hepatitis C virus (HCV) and HIV in Victorian repeat blood donors and to derive the residual risk of transmission of the viruses by screened blood transfusion. The interval from the previous whole blood donation was extracted retrospectively from Victorian Red Cross Blood Bank records for each of the 358332 repeat donations given between March 1994 and December 1995. Records of repeat donors found positive for the viruses in this period were traced to the previous seronegative donation and accepted if screened by the same test. For each virus, the number of previous donations screened by the same test was calculated and the sum of all donation intervals used to derive the incidence of infection in the repeat donor population. Published intervals after infection (when a donation can be infective although seronegative) were used to calculate the risk of release of a seronegative unit which would be infective. Homologous blood donors at the Red Cross Blood Bank of Victoria. Incidence rate of HBV, HCV and HIV in regular blood donors and risk of infective donations being seronegative. The incidence of infection in repeat donors was: HBV: 1.67 per 100000 person-years; HCV: 1.89 per 100000 person-years; and HIV: 1.31 per 100000 person-years. The risk of a seronegative repeat donation being infective was: HBV: 2.71 per million donations (adjusted to 6.45 to account for viraemias which remain seronegative); HCV: 4.27 per million donations; and HIV: 0.79 per million donations. The risk of transmitting HCV, HBV or HIV by repeat blood donors is low and compares favourably with overseas data. Repeat donors have an incidence rate of HIV and HBV comparable to that of the general population, but the incidence rate of HCV is lower for repeat donors than in the general population.

A controlled study of hepatitis C transmission by organ transplantation

Hepatitis C virus (HCV) can be transmitted by transplantation of cadaver organs from donors with antibody to HCV (anti-HCV); therefore, transplantation of organs from anti-HCV positive donors to anti-HCV-negative recipients has been discouraged. We have looked at outcomes in recipients of organs from anti-HCV positive and negative donors to determine whether this advice is well-founded. Stored sera from 716 consecutive cadaver organ donors procured by the New England Organ Bank between 1986 and 1990 were tested for anti-HCV by a first-generation ELISA (ELISA1); 13 (1·8%) were positive. 29 recipients who received organs from these donors were the study group. 37 donors were randomly selected from 703 ELISA1-negative cadaver organ donors. 74 recipients of organs from these 37 donors were the control group. Clinical records were reviewed and recipient sera were tested for anti-HCV with a second-generation ELISA (ELISA2), and HCV RNA was tested for by polymerase chain reaction. Median post-transplant follow-up was 42 and 49 months for study and control groups. Post-transplantation prevalence of anti-HCV and HCV RNA was 67% and 96% among recipients from anti-HCV-positive donors, and 20% and 18% among recipients from anti-HCV-negative donors (p<0·001). Post-transplantation non-A, non-B hepatitis, graft loss, and death were observed in 55%, 52%, and 31% among recipients of organs from anti-HCV-positive donors, and 16%, 53%, and 33% among recipients from anti-HCV-negative donors. In a proportional hazards model, the relative risks for non-A, non-B hepatitis, graft loss, and death among recipients from anti-HCV-positive donors were 4·37 (95% Cl 1·97-9·70), 0·93 (0·51-1·70), and 0·89 (0·41-1·93). Transmission of HCV infection by organ transplantation increased the risk of liver disease among recipients. However, after 3·5 years, donor HCV infection did not adversely affect patient survival or graft survival.

The prevalence of hepatitis C virus (HCV) in infants and children after liver transplantation

Hepatitis C virus (HCV) is an important cause of liver injury following liver transplantation in adults. We hypothesized that the prevalence of HCV infection in children following liver transplantation would be lower than the prevalence in adults after liver transplantation because HCV-related liver disease leading to liver transplantation in children is low and children require less blood products than adults during transplantation. We therefore performed a cross-sectional study to determine the prevalence of HCV infection in children who had undergone liver transplantation. Serum samples were obtained from 62 of 65 (95.4%) consecutive patients surviving for more than six months after transplantation. Using a second-generation enzyme-linked, immunosorbent assay (ELISA-2) and a second-generation recombinant immunoblot assay (RIBA-II), antibodies to HCV were detected in 5.1% (3 of 59) of the subjects. Using a single-step, polymerase chain reaction (PCR), HCV RNA was detected in 6.2% (4 of 62). All HCV-positive children had undergone liver transplantation before the initiation of routine screening for HCV in blood donors; overall 30 patients were transplanted prior to routine screening of blood products for HCV. The prevalence of HCV in infants and children after liver transplantation in our study is substantially less than the rates reported in adults. This difference may be due, in part, to the lower volume of blood product exposure and to the fact that children, as opposed to adults, rarely have chronic HCV infection as a cause of end-stage liver disease.

Prevalence and epidemiological characteristics of hepatitis C in Scottish blood donors.

All blood donors in Scotland who were found to be infected with hepatitis C virus (HCV) in the first 6 months of routine testing of all donations for anti-HCV were contacted. Those who attended were counselled, a history of exposure to risk was sought, and blood was taken for alanine aminotransferase (ALT) level as a measure of liver function. The epidemiological features were then correlated with the virological findings and ALT. In the period under study between September 1991 and February 1992, 180,658 blood donors attended. The prevalence of HCV infection was 0.088%. Of the 151 donors who attended for counselling, 101 (68%) were male. Intravenous drug use was the most common risk activity (39%), followed by previous blood transfusion (15.2%), other parenteral exposure (11.2%) and heterosexual contact with a parenterally infected partner (8.6%); 29.1% of donors gave no history of possible exposure. Elevated ALT levels were found in 59%. ALT levels were higher in donors with HCV types 1 and 3 than in HCV type 2 or non-viraemic donors. The prevalence of HCV in Scottish blood donors is thus relatively low. This may relate to the effectiveness of donor selection procedures, but donors with risk activities which should debar them continue to donate. The combination of ALT and PCR appears to be useful in counselling and assessing infected donors.