Transmission of hepatitis C virus by transfusion in Orebro County, Sweden, 1990-1992

Hepatitis C time trends in reported cases and estimates of the hidden population born before 1965, Denmark and Sweden, 1990 to 2020

BackgroundAccording to the World Health Organization, hepatitis C virus (HCV) infection should be under control by 2030.AimOur aim was to describe the size and temporal changes in reported cases of chronic HCV infection in Denmark and Sweden and to estimate the size of the hidden (undiagnosed) population born before 1965.MethodsWe extracted all HCV infections reported to national surveillance systems in Denmark and Sweden from 1990 to 2020. Prediction of the size of the hidden HCV-infected population was restricted to the cohort born before 1965 and cases reported up to 2017. We applied a model based on removal sampling from binomial distributions, estimated the yearly probability of diagnosis, and deducted the original HCV-infected population size.ResultsDenmark (clinician-based) reported 10 times fewer hepatitis C cases annually than Sweden (laboratory and clinician-based), peaking in 2007 (n = 425) and 1992 (n = 4,537), respectively. In Denmark, the birth year distribution was monophasic with little change over time. In recent years, Sweden has had a bimodal birth year distribution, suggesting ongoing infection in the young population. In 2017, the total HCV-infected population born before 1965 was estimated at 10,737 living persons (95% confidence interval (CI): 9,744-11,806), including 5,054 undiagnosed, in Denmark and 16,124 (95% CI: 13,639-18,978), including 10,580 undiagnosed, in Sweden.ConclusionsThe reporting of HCV cases in Denmark and Sweden was different. For Denmark, the estimated hidden population was larger than the current national estimate, whereas in Sweden the estimate was in line with the latest published numbers.

Transmission of viral hepatitis through blood transfusion in Sweden, 1968 to 2012

Introduction

Viral hepatitis remains a significant threat to transfusion safety, although largely mitigated by donor screening.

Aim

Our objective was to estimate the past and present burden of transfusion transmission of all types of viral hepatitis (A to E) and to find undiagnosed infections with hepatitis C virus (HCV).

Method

We performed a retrospective cohort study using a database of the entire computerised transfusion experience of Sweden from 1968 to 2012 and linking it to a nationwide database of notifiable infections. We then used two independent statistical approaches. Firstly, we tracked recipients of blood from donors with confirmed viral hepatitis. Secondly, we computed a donor-specific risk score, defined as the difference between the observed and the expected number of HCV infections among all previous recipients of all donors, where thresholds were determined using simulation.

Results

Among 1,146,307 transfused patients, more than 5,000 were infected with HCV. Transfusion transmission only occurred before 1992 when donor screening had been completely implemented. Overall, we found 44 donors and 1,180 recipients likely to be infected with HCV who were still alive but who remained undiagnosed.

Conclusion

There is still a substantial number of individuals in Sweden who have probably been infected with HCV through blood transfusion and who are still unaware of their infection. We recommend that a follow-up study should be conducted to validate the method we used by approaching these individuals and offer testing. This would also serve as an opportunity to offer treatment to those who remain infected.

Prevalence of chronic hepatitis C virus infection among childhood cancer survivors in Stockholm, Sweden

Background: Childhood cancer survivors treated before 1992, when blood donor screening for hepatitis C virus (HCV) infection was introduced, are at risk of transfusion-transmitted HCV infection. A national HCV screening campaign targeting blood transfusion recipients was launched in Sweden in 2007-2010. The aims of this study were to, among adult childhood cancer survivors in Stockholm County, investigate the prevalence of HCV infection, the natural course of infection, treatment outcome and anti-HCV testing frequency before, during and after the screening campaign and finally to actively screen the untested ones. Material and Methods: This was a combined retrospective register based and prospective screening study of adult childhood cancer survivors (n = 686) treated for malignancy in Stockholm before 1992. In the first part, we investigated the prevalence of HCV infection and previous anti-HCV testing, and in the second part, we actively traced and HCV-screened the remaining untested cohort living in Stockholm. Analysis of previous documented anti-HCV tests in medical records, laboratory records, and the national communicable disease registry was performed. In the second part, 231 presumably untested individuals were contacted by mail and offered an anti-HCV test. The natural course of HCV infection and treatment outcome was analyzed for those found to be chronically infected. Results: In total, 235 patients were tested and 11 were HCV-RNA positive. The overall prevalence of chronic HCV infection among the tested childhood cancer survivors was thus 4.7% (95% CI = 2.6-8.2%), which is almost 10 times higher than the national prevalence of 0.5%. Only 12% of the Stockholm cohort were tested during the screening campaign in 2007-2010, while the test uptake using active tracing screening within this study was 40% (p < .001). Conclusion: With today's effective treatment options, active tracing and HCV screening of childhood cancer survivors are recommended.

The future disease burden of hepatitis C virus infection in Sweden and the impact of different treatment strategies

OBJECTIVE. Recently, new highly effective direct-acting antivirals (DAAs) against hepatitis C virus (HCV) were introduced. Whether these will alleviate the anticipated increase of liver disease burden in Sweden is unknown, partly because high costs may restrict the use. The objectives were to model the HCV epidemic in Sweden, the burden of disease, and the potential impact of different treatment strategies.

MATERIAL AND METHODS

HCV disease progression was modeled to 2030. Scenarios were simulated using new DAAs with sustained annual treatment rate (n = 1130), reduced treatment rate (n = 380) to maintain budget, and increased treatment rates (n = 1430 or 2260) to reduce HCV infections.

RESULTS

With today's triple therapies, the estimated number of serious liver complications and death are expected to peak in 2021. Using new DAAs among F0-F4 patients, an unchanged annual treatment rate can reduce the number of HCV infections by 10% by 2030; however, hepatocellular carcinoma (HCC) and mortality will remain unchanged. By reducing to 380 treatments annually and focusing on patients with advanced fibrosis (F3-F4), serious complications will remain constant but the total number of HCV infections will increase. By doubling the number of DAA treatments, HCC-incidence and liver-related deaths would decrease by 65-70% by 2030.

CONCLUSION

Mortality and HCC can be reduced with new DAAs and sustained treatment uptake when restricted to F2-F4 patients, or with increased uptake in F0-F4 patients. Treatment restrictions to limit cost may reduce the positive effects and increase the burden of HCV infection. These results may be important for the future strategies of HCV management.

Impact of donor histology on survival following liver transplantation for chronic hepatitis C virus infection: a Scandinavian single-center experience

OBJECTIVE

Survival following liver transplantation for hepatitis C virus (HCV) infection is affected by several factors. The aims of this single-center study were to evaluate survival from 1992 to 2006 in HCV-infected liver transplant recipients and to identify factors influencing patient and graft survival, with particular focus on donor liver histopathology.

MATERIAL AND METHODS

Survival among 84 patients transplanted for HCV-related liver disease at the Sahlgrenska University Hospital during the above period was evaluated. Median follow-up time was 57 months (range 28-87). A perioperative liver biopsy from the donor liver graft was available in 68 cases. Biopsies were assessed for fibrosis, necroinflammatory activity, and degree of steatosis. Patient and graft survival according to relevant factors including donor histopathology were analyzed by Kaplan-Meier analysis.

RESULTS

We found an association between donor liver fibrosis and patient survival (p = 0.016) as well as between graft survival and portal inflammation in the donor liver (p = 0.026). Both these associations remained significant in multivariate analysis (p = 0.007 and 0.017 respectively). Moreover, recipient age over 60 was found predictive of patient survival and repeated steroid boluses or steroid-resistant rejection of graft survival. Donor age was high throughout the study period.

CONCLUSION

Histopathological features, especially portal inflammation and stage of fibrosis, in the donor liver may deleteriously affect graft and patient survival following HCV-related liver transplantation. Thus, pretransplant evaluation of donor histopathology may be of value in the selection of donors for transplantation of HCV-positive individuals, especially among donors older than 60 years.

The burden of hepatitis C in Sweden: a national study of inpatient care

The spread of hepatitis C virus (HCV) in Sweden in the 1970s indicated that serious liver complications (SLC) would increase in the 2000s. The aim of this study was to analyse the burden of HCV-associated inpatient care in Sweden, to demonstrate the changes over time and to compare the findings with a noninfected population. The HCV-cohort (n: 43,000) was identified from the national surveillance database 1990-2006, and then linked to national registers to produce an age-, sex-, and region-matched noninfected comparison population (n: 215,000) and to obtain information on demographics, cancers, inpatient care and prescriptions. Cox regression was used to estimate the likelihood (hazard ratios) for admission to hospital in the HCV compared with the noninfected cohort. The hazard ratios were 4.03 (95% CI: 3.98-4.08) for all care, 77.52 (71.02-84.60) for liver-related care and 40.74 (30.58-54.27) for liver cancer care. The admission rate in the HCV-cohort compared with the noninfected cohort, the rate ratio (age- and sex-adjusted) for all inpatient care was 5.91 (95% CI: 5.87-5.94), and the rate ratio for liver-related care was 70.05 (66.06-74.28). In the HCV-cohort, 45% of all episodes were for psychiatric, mostly drug-related, care. Inpatient care for SLC increased in the 2000s. To conclude, drug-related care was common in the HCV-infected cohort, the demand for liver-related care was very high, and SLC increased notably in the 2000s, indicating that the burden of inpatient care from serious liver disease in HCV-infected individuals in Sweden is an increasing problem.

Cause of death in individuals with chronic HBV and/or HCV infection, a nationwide community-based register study

Studies on chronic viral hepatitis and mortality have often been made on selected populations or in high-endemic countries. The aim of this study was to investigate the causes of death and the mortality rates in the nationwide cohorts of people chronically infected with hepatitis B virus (HBV) and/or hepatitis C virus (HCV) in Sweden, a low-endemic country. All notifications on chronic HBV infection and HCV infection 1990-2003 were linked to the Cause of Death Register. A total of 9517 people with chronic HBV infection, 34 235 people with HCV infection and 1601 with chronic HBV-HCV co-infection were included, and the mean observation times were 6.4, 6.3 and 7.9 years, respectively. The mortality in the cohorts was compared with age- and gender-specific mortality in the general population and standardized mortality ratios (SMR) were calculated. All-cause mortality was significantly increased, SMR 2.3 (HBV), 5.8 (HCV) and 8.5 (HBV-HCV), with a great excess liver-related mortality in all cohorts, SMR 21.7, 35.5 and 46.2, respectively. In HCV and HBV-HCV infected there was an increased mortality due to drug-related psychiatric diagnoses (SMR: 20.7 and 27.6) and external causes (SMR: 12.4 and 11.4), predominantly at younger age. To conclude, this study demonstrated an increased all-cause mortality, with a great excess mortality from liver disease, in all cohorts. In people with HCV infection the highest excess mortality in younger ages was from drug-related and external reasons.

Risk factors for hepatitis B and C in multi-transfused patients in Uruguay

BACKGROUND

In spite of the progress made in the prevention of transfusion-transmitted infections over the last years, these still occur. It was considered that infection by hepatitis B (HBV) and C (HCV) viruses could be a major problem in Uruguay, especially among high-risk individuals, such as multi-transfused patients.

OBJECTIVES

To assess the prevalence of HBV and HCV infection among multi-transfused Uruguayan patients and the impact of serological screening; to evaluate the role of number of transfusions and other potential risk factors for the acquisition of HBV and HCV infection.

STUDY DESIGN

Cross-sectional study of HCV antibodies, HBV surface antigen (HBsAg) and HBV core antibodies (HBcAc) in 409 multi-transfused patients.

RESULTS

Of 409 patients studied, 147 (35.9%) received blood products due to acute bleeding, 118 (28.9%) were hemato-oncological, 75 (18.3%) hemophiliacs, 64 (15.6%) were on hemodialysis and 5 (1.2%) suffered sickle cell anemia. Prevalence of HCV antibody was 12.7%. Of the HCV positive patients, 45 were hemophiliacs, for a prevalence rate of 60.0%. The prevalence rates for hemodialysis and acute bleeding patients were 6.3% and 2.0%, respectively. Prevalence of HBsAg was 1.0%; 16.6% of subjects were positive for HBcAc. The prevalence rates of HBcAc were 48.0%, 15.0% and 3.1% among hemophiliacs, acute bleeding and hemodialysis patients, respectively. There was a direct relationship between the number of products transfused and prevalence of both hepatitis C antibodies and HBcAc. Higher prevalence of HCV and HBcAc was observed among the group of patients who received transfusions before the systematic screening of blood donors.

CONCLUSIONS

Exposure to blood transfusions was the main risk factor for HCV and HBV infection. The systematic serological screening of blood donors was highly effective in reducing transfusion transmitted infections.

Diagnosis and procedure-specific survival among transfusion of recipients in 1993 and 2000, Orebro County, Sweden

BACKGROUND AND OBJECTIVES

Survival rates in patients transfused in 1993 and 2000 were compared in relation to diagnoses and surgical interventions.

MATERIALS AND METHODS

Blood centre and hospital records of all patients transfused from March to May in Orebro County in 1993 (n = 932) and 2000 (n = 990), were matched with the national register of deaths.

RESULTS

Relative risk of death within 1 year, adjusted for diagnoses, operations and other confounders in patients transfused in 2000 compared to 1993 was 0.78 (CI 0.66-0.91). Among those transfused 1993, 39% were alive after 7 years.

CONCLUSION

The improved survival among those transfused in 2000 could not be accounted for by differences in ages or case-mix.

Uses and sources of data on long-term survival after blood transfusion

Several public policy decisions in transfusion medicine require information on the long-term (> or =10-year) survival of transfused patients. This information is needed (1) to estimate the number of surviving transfusion recipients who have contracted a particular infection through transfusion, (2) to assess the cost-effectiveness of measures introduced to further improve the safety of the allogeneic blood supply, (3) to estimate the total anticipated number of transfusion-transmitted cases of disease when a novel transfusion-transmitted infection with a long incubation period emerges, and (4) determine the scope of any proposed lookback investigation in terms of the length of time that should be covered retrospectively by the lookback effort. Although the probabilities of survival of Olmsted County, MN, residents transfused in 1981 were often used previously when input data on long-term posttransfusion survival were needed in the United States, these data most likely do not reflect the survival of patients transfused in the 1990s. Recent data from Sweden, Northern England, and New York City suggest that the short-term (up to 5 years posttransfusion) probabilities of survival reported from Olmsted County may have to be reduced by up to 20% before they can be used for making public policy decisions in the future, and that probabilities of survival of 66%, 60%, and 47%, respectively, at 1, 2, and 5 years posttransfusion may reflect the life expectancy of subjects transfused in the 1990s. No empirical data on the 10-year probability of survival of such patients are currently available from population-based studies, but some data suggest that the 10-year survival of an unselected population transfused in 1988 to 1990 may be 40%. A population-based study that includes several US counties has to be undertaken to generate the information needed for public policy decisions in the future.

Four-year survival of transfusion recipients identified by hepatitis C lookback

BACKGROUND

Information on the probability of survival of transfused patients is needed for policy making, but there is a paucity of empirical research into this question. A Swedish population-based study reported that the 40-month posttransfusion probability of survival was 51 percent in all patients and 41 percent in recipients of more than 10 units of blood and blood components. These figures were 20 percent lower than the figures reported previously from Olmsted County, Minnesota.

STUDY DESIGN AND METHODS

Information was collected on the 4-year survival of 695 patients transfused at the New York University Medical Center between 1988 and 1996. These patients had been identified previously by hepatitis C lookback.

RESULTS

Seventy-five percent of patients survived at 1 month after transfusion, 66 percent at 3 months, 60 percent at 6 months, 54 percent at 1 year, 50 percent at 2 years, 45 percent at 3 years, and 41 percent at 4 years. Seventy-eight percent of patients included in the study had received more than 10 units of blood and blood components. The 4-year survival of patients receiving 1 to 3, 4 to 10, or more than 10 units was 62 percent, 48 percent, and 38 percent, respectively (p < 0.0001).

CONCLUSIONS

When transfusion dose is taken into account, the probability of survival of patients transfused at the New York University Medical Center in 1988 to 1996 and identified by lookback is similar to that reported for Swedish county residents transfused in 1993. Based on both the Swedish data and the information presented here and in the absence of any recent results from population-based studies, the survival of U.S. patients transfused in the 1990s appears to be 20 percent lower than that of Olmsted County residents transfused in 1981.

Health and economic consequences of HCV lookback

BACKGROUND

Several countries have conducted or are considering campaigns of lookback on blood recipients who may have acquired posttransfusion HCV (PT-HCV) before the implementation of anti-HCV screening. There is, however, no estimation of the health and economic consequences of the medical interventions triggered by the lookback.

STUDY DESIGN AND METHODS

This study used a Monte Carlo simulation of a Markov model representing the natural history of PT-HCV. Unadjusted and quality-adjusted life expectancy and lifetime medical costs were calculated for a cohort of patients in whom PT-HCV is diagnosed through the lookback, and these values were compared with those calculated for a similar cohort on whom lookback is not performed.

RESULTS

The model predicts that 47 percent of people who received transfusions of HCV-infective blood 10 years ago are still alive, carry the infection, and have not yet progressed to end-stage liver failure. In this population, forthcoming complications of PT-HCV will reduce the remaining life expectancy by 1.75 years per patient. Medical interventions triggered by the diagnosis of PT-HCV would salvage 0.123 years of life expectancy, at a net cost of $921 per newly diagnosed patient. The health and economic impact of diagnosing a new case of PT-HCV through lookback was sensitive to the patient's age, the efficacy of antiviral therapies, the time elapsed from transfusion to lookback, and the future inflation of costs of treating end-stage liver disease. Under some plausible assumptions, the intervention could result in net financial savings for the health care system, but it may also produce a net health loss for the majority of patients who will be said to be HCV-positive without being offered an effective therapy.

CONCLUSION

Diagnosis of PT-HCV through HCV lookback has a potential both to increase patients' life expectancy and to reduce health care costs. However, more effective antiviral therapies and a better knowledge of factors predicting the progression of PT-HCV are needed to attain those goals. Meanwhile, care should be taken to avoid pursuing a health gain for a minority that might result in a health loss for the majority.

HCV lookback in the United States: effectiveness of an extended lookback program

BACKGROUND

In 1998, the FDA recommended look-back for HCV. The recommendation was initially limited, however, to donors who reacted on a multiantigen HCV screening test and to components collected since January 1, 1988. A lookback program was extended to include donors who reacted on the first-generation (single-antigen) HCV screening test and who were positive on a supplemental assay (RIBA-1 or -2) and all components for which transfusion records could be found (back to 1978).

STUDY DESIGN AND METHODS

The yield of the incremental lookback programs was compared to that originally recommended by the FDA by comparing the number of newly identified HCV-positive recipients in each program. The results of lookbacks were reviewed on 385 blood components for which 314 transfusion recipients were identified.

RESULTS

Of the 135 recipients in the FDA program, 70 percent were dead, 28 percent were living and notified, and 2 percent could not be located. In the incremental programs, there were 179 recipients, of whom 80.4 percent were dead, 16.2 percent were living and notified, and 3.4 percent could not be located. Most adult recipients were dead (81%), but the majority of pediatric recipients were alive (57%); 76 percent of tested recipients were HCV seropositive, with no significant difference between programs. One-half of test-positive recipients in each program were newly identified through the lookback program. Seven of the 20 newly identified HCV-positive recipients were found through the incremental programs. The yield, defined as newly detected HCV cases per total number of recipients, was 9.6 percent for the FDA and 3.9 percent for the incremental programs. This difference was significant (p = 0.04).

CONCLUSION

The yield of both programs was limited by the high percentage of recipients who had died. Pediatric recipients were more likely to be living at the time of notification. The incremental program was less efficacious than the FDA program in identifying newly HCV-positive recipients, but one-third of the newly detected HCV cases were identified through the incremental program.

Evaluation of the effectiveness of targeted lookback for HCV infection in the United States-interim results

BACKGROUND

As part of a nationwide program to identify persons at increased risk for HCV infection, persons who received blood from donors who later tested positive for anti-HCV are being directly notified.

STUDY DESIGN AND METHODS

In December 1999, all 198 blood collection establishments (BCEs) and 5442 hospital transfusion services (TSs) in the United States were surveyed by mailed questionnaire to evaluate their progress in carrying out this notification.

RESULTS

Eighty-one percent of the BCEs and 64 percent of the TSs responded. After correcting for nonresponse, an estimated 98,484 components at potential risk for transmitting HCV, according to previous testing of multiantigen-screened donors, were identified nationwide, of which 85 percent had been transfused to recipients. Lookback for these recipients was completed for 80 percent, of whom 69 percent had died. Of those living, 78 percent were successfully notified. An estimated 49.5 percent of those notified were tested; 18.9 percent of those tested were anti-HCV positive, and 32 percent of that group knew they were positive before notification. On the basis of an 85.5 percent reported completion rate for component notifications back through 1988, an estimated 1520 persons will have been newly identified as anti-HCV-positive when lookback related to multiantigen screening of donors is completed.

CONCLUSION

Targeted lookback related to previous multiantigen screening of donors will identify <1 percent of the estimated 300,000 HCV-positive persons in the United States who may have acquired their infection via blood transfusion.

Targeted hepatitis C lookback: Quebec, Canada

BACKGROUND

Since March 1990, all blood donations in Canada are screened for antibodies to hepatitis C virus (HCV). Because HCV may cause chronic asymptomatic hepatitis, in February 1995, the Canadian Red Cross began targeted HCV lookback studies.

STUDY DESIGN AND METHODS

From March 1990 to March 1997, the Quebec Center of the Canadian Red Cross collected 1,750,846 donations, and there were 561 anti-HCV-positive repeat donors, from whom 3,196 blood components had been issued to the hospitals. Hospital blood bank directors were asked to test recipients and return results to the Quebec Center. One hundred nine hospitals were surveyed to determine methods and resources involved in lookback. The transfusion medicine service at the Royal Victoria Hospital (RVH) developed a standard operating procedure for performing lookbacks and analyzed the costs and outcomes of lookbacks.

RESULTS

As of April 1998, information has been received on 2329 (73%) of components; 1020 patients had died of unrelated causes, 590 were untraceable, and 353 were tested. Of those tested, 215 (61%) were anti-HCV positive; their average age was 47, and at least 53 percent were already aware of their HCV status. Few hospitals had received any additional resources to perform lookbacks. At the RVH, lookback on 182 components resulted in the identification of nine seropositive recipients, average age 70, who did not previously know their HCV status; four of these patients had abnormal alanine aminotransferase levels. The cost of lookback per newly diagnosed case of HCV was estimated at $2727 (US) for the Quebec Center and $6014 (US) for the RVH.

CONCLUSION

Targeted lookback in the province of Quebec on 3196 components has resulted in the identification of 101 seropositive recipients who did not previously know their HCV status.

Transfusion-acquired hepatitis C: the Danish lookback experience. The Danish HCV [hepatitis C virus] Lookback Group

BACKGROUND

In 1996, the Danish National Board of Health recommended hepatitis C virus (HCV) lookback to identify recipients of blood components from donors found to be positive since the implementation of anti-HCV screening in 1991.

STUDY DESIGN AND METHODS

The aim was to accumulate results of the lookback at a national level and to describe the morbidity of the infected recipients. Records of transfusion were identified for at least 10 years back, and recipients still alive were tested for hepatitis C. Those with positive results were referred for clinical evaluation.

RESULTS

A total of 150 anti-HCV-positive Danish donors had donated blood to 1018 transfusion recipients, of whom 288 (29%) were still alive. Because of age, malignancy, or other severe diseases, 118 (41%) of these were not contacted. Of 157 recipients screened for HCV, 128 (82%) were anti-HCV positive on enzyme-linked immunosorbent assay, and 88 (56%) were HCV RNA positive. Among the HCV RNA-positive recipients, symptoms were present in 38 percent (25/66 reported), elevated alanine aminotransferase was found in 53 percent (41/77 tested), and cirrhosis was found in 11 percent (6/54 biopsied). Treatment with interferon alpha was initiated in 23 patients, corresponding to 26 percent of HCV RNA positive recipients.

CONCLUSION

Among tested recipients in the Danish HCV lookback, most were anti-HCV positive and more than half were still viremic. The morbidity was considerable, and one-fourth of viremic recipients entered treatment.

Hepatitis C virus transmission, 1988-1991, via blood components from donors subsequently found to be anti-HCV-positive

The recipients of blood components, from the first 12 anti-hepatitis C virus (HCV) positive donors identified by blood donor screening, 1985-1991, were traced retrospectively and tested to assess the HCV transmission rate, HCV genotypes and disease severity. Three enzyme-linked immunosorbent assay (ELISA) positive but RIBA-indeterminate and HCV RNA-negative donors did not transmit HCV to their 9 traced recipients. Nine RIBA- and HCV RNA-positive donors had donated blood to 27 now living recipients of whom 16/27 (59%) were viraemic 1-5 years later. Nine recipients had resolved infection, as determined by PCR HCV RNA. Five of these were RIBA-2 positive but HCV RNA-negative and 4 recipients were RIBA-2-indeterminate and HCV RNA-negative. Two recipients negative in all tests had probably received blood before the donor became infected with HCV. The HCV genotype in each case was identical between the donor and the recipient. Of the viraemic recipients, 50% (8/16) were unsuitable for further investigation or therapy due to their high age and/or underlying severe disease. At most, only 30% (8/27) of the recipients were suitable for further investigation and/or treatment. Two of these were already diagnosed as being infected with HCV before being traced. It is concluded that the benefit of a general tracing of recipients of blood components from HCV-infected donors is doubtful since only a few of them are suitable candidates for treatment. Our results seem to indicate that it is more appropriate to recommend anti-HCV testing to those seeking medical care who have received transfusions or undergone major surgery before 1992, i.e. before anti-HCV-screening was initiated.