Patients' perceptions of blood transfusion risks in Karachi, Pakistan.

OBJECTIVE: To evaluate the understanding of and attitudes toward risks of blood transfusions among transfusion recipients in Karachi. METHODS: One hundred forty-one transfusion recipients from 13 major Karachi hospitals were interviewed. Indications for transfusion were obtained by reviewing the patients' medical records. RESULTS: The most common indications for transfusion were surgical complications (n = 77, 55%), anemia (n = 34, 24%), and generalized weakness (n = 15, 11%). Most recipients (n = 103, 80%) had never heard of viral hepatitis, and 44 (31%) had never heard of acquired immunodeficiency syndrome (AIDS). Ninety-four recipients (66%) believed that generalized weakness was a valid indication for blood transfusion. Sixty-nine recipients (49%) were not willing to pay an increased price for blood that was screened for blood-borne pathogens. CONCLUSIONS: Blood recipients in Karachi are unaware of the risks of transfusions, and the reasons given by the ordering physician for many of the transfusions were not consistent with international guidelines. Steps to educate the public about the risks of transfusions and practitioners about the indications for transfusion could prevent blood-borne virus transmission in Karachi.     

Prospective controlled study of posttransfusion hepatitis after cardiac surgery in a large referral hospital in India

ABSTRACT— We studied the risk of post-transfusion hepatitis (PTH) in recipients of blood collected from voluntary donors screened for HBsAg. Two hundred and fifty patients without any previous history of liver disease or transfusion were followed up for 12 months subsequent to cardiac surgery. Thirty-five of them had closed-heart surgery without receiving transfusion and served as controls. The remaining 215 patients received single-point transfusions (mean 4 ± 2.4 units). None of the controls and 15 (6.9%) blood recipients developed PTH. Three (20%) patients had hepatitis-B-virus-induced hepatitis while the remainder (80%) had non A, non B (NANB) hepatitis. The number of units of blood transfused and surrogate markers for development of PTH (donor alanine aminotransferase, anti-HBc and anti-HBs antibody) were not associated with the occurrence of PTH (p>0.05). Nine (60%) of the 15 patients developing PTH were asymptomatic. All the patients recovered from the PTH, except one who died of fulminant hepatitis. At the end of 1 year of follow-up, none of the patients had evidence of chronic hepatitis. Only three (25%) of the patients with NANB-PTH developed anti-hepatitis C virus (HCV) antibody during the follow-up. We conclude that the incidence of PTH in India is similar to other parts of the world and NANB virus was the major cause of the PTH. The absence of chronicity and lack of seroconversion to anti-HCV antibody in the majority of the patients after 1 year of follow-up may suggest the possibility of a NANB virus other than HCV as the major cause of PTH in India.     

Autologous blood transfusion in elective heart surgery: prospective study of 189 consecutive patients

Blood autotransfusion has entered a new phase in blood transfusion technique, since it represents an important alternative in eliminating the risks connected with blood transfusion: viral hepatitis, AIDS, blood transfusion reactions, and alloimmunization. Transfusion requirements during cardiac surgical procedures have steadily decreased; nowadays most adult patients require no transfusion during surgery. Patients (pts) receiving bank-blood may develop infectious diseases (hepatitis, AIDS, etc.). We have studied how to avoid the risk of infections with homologous blood transfusions. We present our experience of day-hospital pre-operative autologous blood collection. One-hundred-eighty-nine patients undergoing primary myocardial revascularization or valvular replacement were submitted to the drainage of 350 ml of blood three times every four days before surgery. The blood was centrifuged at once, to separate red cells from plasma. Surgeries were performed 21 days after the first drainage; iron therapy was recommended. After surgery pts received blood only if haematocrit was lower than 28%. The following data were recorded: no. of pts who received homologous blood; blood loss and homologous total blood volume used for each pt. Average blood loss was 1230 cc for ischemic pts and 701 cc for valvular pts. Non-A non B hepatitis occurred in 3/189 pts (1.5%). All of them had received homologous blood transfusions. Our data show clearly that autotransfused pts had a better post-operative period; less bank-blood and fewer transfusions have been used. No pt had collateral effects such as angina or hypotension from blood drawing. Our data show that severe cardiac diseases do not represent an absolute contraindication to heavy blood drainage.(ABSTRACT TRUNCATED AT 250 WORDS)     

Infection with human immunodeficiency virus type 1 (HIV-1) among recipients of antibody-positive blood donations

OBJECTIVE: To assess the incidence of human immunodeficiency virus type 1(HIV-1) transmission by antibody (anti-HIV-1)-positive blood components, and to determine the immunologic and clinical course in HIV-1-infected recipients. DESIGN AND SUBJECTS: We retrospectively tested approximately 200,000 donor blood component specimens stored in late 1984 and 1985 for anti-HIV-1, and we contacted recipients of positive specimens to determine their serologic status. They were compared with both recipients of HIV-1-negative transfusions and healthy (untransfused) controls. Subjects were seen at 3- to 6-month intervals for up to 4 years for clinical and immunologic evaluations. MEASUREMENTS AND MAIN RESULTS: Of 133 recipients, 9 had other possible exposures. Excluding these cases, 111 of 124 (89.5%) were anti-HIV-1-positive (95% CI, 84.1% to 94.5%). The recipient's sex, age, underlying condition, and type of component did not influence infection rates. The cumulative risk for developing the acquired immunodeficiency syndrome (AIDS) within 38 months after transfusion was 13% (CI, 7.5% to 21.6%). At 36 +/- 3 months after the index transfusion, seropositive recipients had lower counts of CD2+CDw26+, CD4+, CD4+CD29+, and CD4+CD45RA+subsets and more CD8+I2+ lymphocytes than did recipients of anti-HIV-1-negative transfusions. The CD4+ and CD2+CDw26+subsets changed the most rapidly. The absolute CD8+ count remained normal. CONCLUSIONS: Transfusion of anti-HIV-1-positive blood infected 90% of recipients. The rate of progression to AIDS within the first 38 months after infection was similar to that reported for homosexual men and hemophiliacs. Although most lymphocyte subset counts changed over time, CD8+ counts were constant.     

Prospective controlled study of post-transfusion hepatitis after cardiac surgery in a large referral hospital in India.

We studied the risk of post-transfusion hepatitis (PTH) in recipients of blood collected from voluntary donors screened for HBsAg. Two hundred and fifty patients without any previous history of liver disease or transfusion were followed up for 12 months subsequent to cardiac surgery. Thirty-five of them had closed-heart surgery without receiving transfusion and served as controls. The remaining 215 patients received single-point transfusions (mean 4 +/- 2.4 units). None of the controls and 15 (6.9%) blood recipients developed PTH. Three (20%) patients had hepatitis-B-virus-induced hepatitis while the remainder (80%) had non A, non B (NANB) hepatitis. The number of units of blood transfused and surrogate markers for development of PTH (donor alanine aminotransferase, anti-HBc and anti-HBs antibody) were not associated with the occurrence of PTH (p greater than 0.05). Nine (60%) of the 15 patients developing PTH were asymptomatic. All the patients recovered from the PTH, except one who died of fulminant hepatitis. At the end of 1 year of follow-up, none of the patients had evidence of chronic hepatitis. Only three (25%) of the patients with NANB-PTH developed anti-hepatitis C virus (HCV) antibody during the follow-up. We conclude that the incidence of PTH in India is similar to other parts of the world and NANB virus was the major cause of the PTH. The absence of chronicity and lack of seroconversion to anti-HCV antibody in the majority of the patients after 1 year of follow-up may suggest the possibility of a NANB virus other than HCV as the major cause of PTH in India.     

Post-Transfusion Hepatitis: Current Risks and Causes

Viral hepatitis which follows transfusions (post-transfusion hepatitis) may be due to those transfusions, i.e., transfusion-transmitted hepatitis (TTH), or may be incident to the reason for the transfusion and, thus, may be transfusion-associated, but not transfusion-transmitted. The current risks of TTH, today, are extremely small, but are still due, primarily, to the hepatitis B virus (HBV) and the hepatitis C virus (HCV), the latter, formerly being known as “non-A, non-B hepatitis.” The residual, now, of TTH which is non-A, non-B, and non-C is extremely small and may be due to a variety of agents. Using volunteer (unpaid), repeat, blood donors, who are carefully screened for hepatitis risk factors and then tested for evidence of HBV infection, the risk of HBV being transmitted by a transfusion today is in the order of 1 per 63,000 units of blood. For transfusion-transmitted HCV, with the same repeat, volunteer (unpaid) donors, careful screening and a sensitive assay for anti-HCV, the risk is in the order of 1 in 125,000 units. These risks of HBV and HCV due to transfusions are so small that other means of acquiring these viruses should be sought when patients develop hepatitis following blood transfusions. However, efforts to further reduce the current risks of HBV and HCV transmission by transfusions should continue; these include restricting transfusions to those which are necessary or appropriate, utilizing alternatives to transfusion, employing novel assays to detect viral nucleic acids, and, finally, implementing various microbial inactivation techniques on blood, blood components and plasma derivatives.     

A prospective study of posttransfusion hepatitis in Taiwan.

In a follow-up study of 6 months or more of two hundred and ninety-six patients who had received blood transfusion, 37 (12.5%) developed acute posttransfusion hepatitis. Patients with posttransfusion hepatitis had significantly higher donor numbers and transfusion amounts than patients without hepatitis. Frequency was not related to the age, sex or hepatitis B carriage of recipients. There were no cases of fulminant hepatitis. Of 37 patients with hepatitis, 36 were diagnosed as non-A, non-B hepatitis and one as hepatitis B. Twenty-two (59.5%) of the 36 patients with non-A, non-B hepatitis seroconverted to hepatitis C antibody. Two of these were positive for hepatitis C antibody before transfusion and 12 were negative for hepatitis C antibody. Thirty-three of the 36 patients were followed-up for more than 6 months after the onset of hepatitis. While 13 of the 33 patients recovered, the remaining 20 (60.6%) patients still had persistent liver test abnormalities 6 months after the onset of hepatitis. Seventeen (85%) of the 20 patients who developed chronic hepatitis were hepatitis C antibody positive. In contrast, only four (30%) of the 13 patients who recovered after acute hepatitis were positive for the hepatitis C antibody. Chronicity rate was not related to the patient's sex, age, transfusion amount or donor number. Our results suggest a high frequency of posttransfusion hepatitis C in Taiwan and that the infection has a high risk of chronicity.     

Antibody to hepatitis B core antigen as a paradoxical marker for non-A, non-B hepatitis agents in donated blood

The relationship between the presence of antibody to hepatitis B core antigen (anti-HBc) in donor blood and the development of hepatitis in recipients of that blood was studied in 6293 blood donors and 481 recipients who were followed for 6 to 9 months after transfusion. Of 193 recipients of at least 1 unit of blood positive for anti-HBc, 23 (11.9%) developed non-A, non-B hepatitis compared with 12 (4.2%) of 288 recipients of only anti-HBc-negative blood (p less than 0.001). Donor anti-HBc status was not significantly associated with the development of hepatitis B in the recipient and was negatively associated with the development of cytomegalovirus hepatitis. The relationship of donor anti-HBc status and the development of non-A, non-B hepatitis in the recipient was independent of transfusion volume and elevated donor transaminase level. Although 88% of anti-HBc-positive blood units were not associated with recipient non-A, non-B hepatitis, calculation of maximal corrected efficacy predicted that exclusion of anti-HBc-positive donors might have prevented 43% of the cases of non-A, non-B hepatitis with a donor loss of 4%. Because of the serious chronic consequences of non-A, non-B hepatitis, surrogate tests for non-A, non-B virus carriers must be seriously considered.     

Mortality after transfusions, relation to donor sex

Introduction Blood products from female donors have been associated with worse outcome after blood transfusions. We aimed to quantify the association of overall mortality with transfusions from female blood donors. Methods We performed a cohort study of all transfusion recipients during a 5‐year period at the Leiden University Medical Center. Analyses were performed in a sub‐cohort of recipients with all transfusions from donors of the same sex. Effects in male and female recipients were analysed both separately and averaged, for an overall estimate. Results Overall, when averaged over both male and female recipients, transfusions from female donors were not associated with increased mortality. However, in male recipients transfusions from female donors were positively associated with mortality, while in female recipients the association was reversed. The hazard ratio for mortality after sex‐mismatched transfusions was 1·2 (95% CI, 0·98–1·4). In recipients aged 1–55 it was 1·8 (95% CI, 1·2–2·7). In recipients over 55, with more other risk factors for mortality, it was 1·0 (95% CI, 0·83–1·2). Conclusions Overall transfusions from female donors were not associated with increased mortality. However, male recipients of blood from female donors did have an increased risk of death. Female recipients of blood from male donors showed a weaker increase in mortality.     

Occult hepatitis B virus infection as a cause of posttransfusion hepatitis in patients with cancers

Background

Prevalence of hepatitis B virus (HBV) infection is increased in patients of cancer with increased mortality. Multiple transfusions of blood and blood-related products are a potential source.

Aims

This study aims to assess the incidence of hepatitis B surface antigen (HBsAg) seroconversion in cancer patients receiving transfusion of blood or blood-related products and identify possible reasons for infection in these patients.

Material and Methods

Patients of cancer receiving blood products, who were HBsAg-, anti-hepatitis B core (HBc)-, and HBV DNA-negative prior to transfusion, were tested for HBsAg by ELISA at 6, 12, and 24 weeks after the last transfusion. Blood donors were screened for HBsAg by ELISA.

Results

Twenty of 3,600 (0.56 %) blood donors tested positive for HBsAg and were rejected. Nine of 150 (6 %) cancer patients became HBsAg-positive posttransfusion which included seven patients who presented with acute hepatitis B and other two patients who remained HBsAg-positive without hepatitis. In 6/9 (66.6 %) patients, HBsAg positivity was related to blood transfusion as their corresponding blood donors on retesting the stored samples were positive for anti-HBc antibody and HBV DNA. In other three patients, the cause of their HBsAg positivity could not be ascertained.

Conclusion

Occult HBV infection in blood donors is a potential source of posttransfusion HBV infection in recipients. Anti-HBc antibody and HBV DNA should be tested in blood donors especially when blood is given to cancer patients receiving chemotherapy.     

TT viral infection through blood transfusion: retrospective investigation on patients in a prospective study of post-transfusion hepatitis

AIM To investigate the role of blood transfusion in TT viral infection (TTV).METHODS We retrospectively studied serum samples from 192 transfusion recipients who underwent cardiovascular surgery and blood transfusion between July 1991 and June 1992. All patients had a follow-up every other week for at least 6 months after transfusion. Eighty recipients recipents blood before screening donors for hepatitis C antibody (anti-HCV), and 112 recipients reveiver screened blood.Recipients with alanine aminotransferase level ＞ 2.5 times the upper normal limit were tested for serological markers for viral hepatitis A, B,C, G, Epstein-Barr virus and cytomegalovirus.TTV infection was defined by the positivity for serum TTV DNA using the polymerase chain reaction method. RESULTS Eleven and three patients, who reveiver anti-HCV unscreened and screened blood, respectively, had serum ALT levels ＞90 IU/L. Five patients (HCV and TTV: 1; HCV,HGV, and TTV: 1; TTV: 2; and CMV and TTV: 1 )were positive for TTV DNA, and four of them had sero-conversion of TTV DNA. CONCLUSION TTV can be transmitted via blood transfusion. Two recipients infected by TTV alone may be associated with the hepatitis.However, whether TTV was the causal agent remains unsettled, and further studies are necessary to define the role of TTV infection in chronic hepatitis.     

Posttransfusion hepatitis in Toronto, Canada

Five hundred seventy-six consecutive patients from the surgical, obstetrical, and medical services who had received transfusions of volunteer blood were followed-up at regular intervals for 6 mo. Fifty-three (9.2%) developed acute posttransfusion non A, non B hepatitis. Forty-seven (89%) had an incubation period between 2 and 8 wk. The frequency was not related to the age or sex of the patient, the indications for transfusion, the type of surgery, anesthesia, the presence of perioperative hypotension, or the number of units of blood transfused. There were no cases of fulminant hepatitis. Nineteen of the 53 patients (36%) with acute posttransfusion hepatitis progressed to chronic hepatitis. Development of chronic hepatitis was not related to the age or sex of the patient, the incubation period of the preceding acute hepatitis, the presence of shock or malignancy, or the number of units of blood transfused. Patients with higher levels of alanine aminotransferase during the acute hepatitis were more prone to develop chronic hepatitis. The finding of 9.2% of transfusion-related hepatitis in recipients of hepatitis B surface antigen-screened blood from volunteer donors underscores the potential sequelae of blood transfusion, especially as a source of contribution to the pool of chronic liver disease.     

Hepatitis after cardiosurgery. Frequency and causes. Results of a prospective study with use of autologous blood

In a prospective study on the causes and frequency of hepatitis after operations on the open heart, two homogeneous groups of patients were formed. In one of them, the amount of homologous blood was reduced to half by means of preoperative donations of autologous blood, the total blood requirement remaining the same. Hepatitis occurred postoperatively in 10% of the cases. The factors which gave rise to the hepatitis were large-pool clotting preparations, transfusion with homologous blood and cross-infection in the hospital. Even after exclusion of other risk factors, the frequency of hepatitis among the recipients of coagulation preparations was around 60%. The frequency of the cases of hepatitis due to foreign blood was about 5 per 100 patients or about 1 per 100 units of blood. By use of autologous blood collected preoperatively, the risk due to transfusion could be lowered by 50%. In polytransfusion, a disproportionately high rise in the risk of hepatitis was observed. It is probably to be ascribed to unknown factors in the hospital environment ("nosocomial hepatitis").     

Prevention of transfusion-associated HIV transmission in Kinshasa, Zaire: HIV screening is not enough

The purpose of this study was to develop a strategy to reduce transfusion-related HIV transmission which went beyond the limits of routine HIV screening of blood donors. Current blood transfusion practices were assessed in 1044 patients for whom staff physicians had requested a transfusion between 5 September and 19 October, 1988. Children under 5 years of age with malaria, and pregnant women with acute anaemia requiring blood transfusion were the two highest risk groups. Many of the transfusions were given without an obvious medical indication; 22.7% (214 out of 955) of the recipients were transfused without prior laboratory tests [haemoglobin (Hb) or haematocrit (Hct)], 7.2% with Hb greater than 6g/100ml or Hct greater than 25% and 16.6% without clinical signs of severe anaemia (pulse less than 100/min without shortness of breath). The data of this study were used to organize a workshop for all the physicians responsible for blood transfusions in Kinshasa and two nearby health zones. A consensus statement on the indications for blood transfusion was developed. Subsequently, transfusion centres adopted this consensus statement instead of previous guidelines.     

Australia Antigen and Posttransfusion Hepatitis

Abstract. The incidence of posttransfusion hepatitis reported in Copenhagen was studied for 2 consecutive years. The 2 years were comparable in every respect, including the number of transfusions (21,000 per year). In the first year no screening of transfusion blood was made, while in the second year all units of blood were systematically screened for Au antigen by a counterelectrophoresis method. During that year, 49 Au antigen-positive units were detected and refused.
The number of cases of transfusion hepatitis officially registered during the 2 years was 9 and 8, respectively. Detailed diagnostic studies revealed that the probable number of cases classifiable as transfusion hepatitis was 8 and 6 in the 2 years. Thus, in the present study screening of transfusion blood for Au antigen has not resulted in an obvious reduction in the incidence of transfusion hepatitis. Three patients were repeatedly examined for more than 6 months after transfusion of a unit of Au antigenaemic blood, but no case or hepatitis or Au antigenaemia was found. Our findings may be related to the fact that cases of acute and chronic hepatitis are unusual among Au antigenaemic Danish blood donors. Further studies are necessary to elucidate the correlation between donor Au antigenaemia, donor liver disease and hepatitis infectivity of donor blood.     

Hepatitis C virus infection in patients with haematological diseases: evidence for the association with erythrocytes transfusion and liver disease

We analysed hepatitis C virus risk factors in 131 consecutive patients with haematological malignancies (17.6% anti-HCV positive), 42 with connective tissue diseases (30.9% anti-HCV positive) and 1071 (1.1% anti-HCV positive) new blood donors. Anti-HCV was associated with elevated serum ALT levels (P = 0.0001) and with red cells (P = 0.045), but not with platelets and plasma transfusions. HCV presence in immunocomplexes immunoadhering on the erythrocytes might explain the association between HCV infection and red cell transfusion. However, other risk factors have to be implicated in haematological malignancies to explain the high anti-HCV prevalence in patients who did not receive blood products.     

Seroconversion rate, mortality, and clinical manifestations associated with the receipt of a human immunodeficiency virus-infected blood transfusion in Kinshasa, Zaire

To evaluate the consequences of receiving human immunodeficiency virus type 1 (HIV-1)-seropositive blood, 90 HIV-1-seronegative recipients of HIV-1-seropositive blood (case patients) and 90 HIV-1-seronegative recipients of HIV-1-seronegative blood, matched for age, sex, number of transfusions, diagnosis, and severity of illness (controls), were followed for 12 months after transfusion at Mama Yemo Hospital in Kinshasa, Zaire. Of case patients and controls, 72% were children transfused for anemia caused by malaria. Of the 46 case patients case patients alive 6 months after transfusion and for whom HIV-1 serologic results were obtained, 44 (96%) had seroconverted. Significantly more case patients (47%) than controls (16%) died within 1 year after transfusion (P less than .001). In the first 3 months after transfusion, fatigue, diarrhea, fever, cough, pruritus, pallor, oral candidiasis, polyadenopathy, hepatosplenomegaly, and rhinorrhea were observed more often among seroconverters than controls (P less than .04). Six percent of case patients and no controls had developed clinical AIDS after 12 months of follow-up. These findings underscore the urgent need for appropriate HIV screening facilities in transfusion centers worldwide.     

The risks of blood transfusion: the relative influence of acquired immunodeficiency syndrome and non-A, non-B hepatitis.

PURPOSE: The acquired immunodeficiency syndrome epidemic has greatly increased concern about the risk of blood transfusion. Many transfusions are now autologous, and when these are not available, both physicians and patients are more likely to question the advisability of transfusion. We evaluate the risk of preoperative blood transfusion and the contribution of human immunodeficiency virus (HIV) infection to that risk. METHODS: We used decision analysis to characterize the risk associated with HIV infection in days of life lost. The contributions to risk of acute transfusion reaction, hepatitis B, and non-A, non-B hepatitis are also estimated. Sensitivity analyses show the implications for transfusion risk of recent information about HIV infection in the blood supply and a new test for hepatitis C. RESULTS: The analysis shows that the contribution of HIV infection to the risk of death from transfusion, expressed in days of life expectancy lost, has become extremely small over the last several years. Currently, HIV infection accounts for less than 1% of the risk of death, while non-A, non-B hepatitis accounts for 97% to 98%. Further reductions in the risk of HIV infection, even to zero, will make relatively little difference in the safety of transfusion. The analysis also shows that the remaining risk from transfusion should decrease sharply, by more than two thirds, with the adoption of the test for hepatitis C. CONCLUSIONS: Efforts to improve the safety of blood should focus on reducing the risk of non-A, non-B hepatitis. The remaining risk of HIV infection is very small.     

The influence of dose of transfusion and component of blood on the incidence of post-transfusion hepatitis

Two thousand five hundred ninety-six consecutive patients who received blood transfusion for the first time within one week and had no liver dysfunction before transfusion had been selected from 8637 patients who received blood transfusion at the hospital between 1982 and 1987. The influence of dose, components of transfused blood and sex, age of recipients on the incidence of post-transfusion hepatitis was investigated. The rate of development of hepatitis depended on the dose of transfusion, not on sex and age of recipients. The rate of development of hepatitis raised as number of transfused blood increased without limiting point to 100%. The carrier rate of healthy population of non-A, non-B hepatitis virus was estimated 1.39%. Stored blood, concentrated red blood cell and fresh blood are high risk components and fresh frozen plasma was low risk component.     

Evidence that use of a second-generation hepatitis C antibody assay prevents additional cases of transfusion-transmitted hepatitis

SUMMARY. The aim of this study was to determine if using hepatitis C antibody (anti-HCV) enzyme immunoassay version 2.0 (EIA2) in addition to version 1.0 (EIA1) increased the safety of the blood supply. Blood non-reactive by anti-HCV EIA1 was transfused in 1990-92. Stored samples from 40098 units, donated prior to 13 March 1992 were later tested by EIA2. For donor units reactive for anti-HCV by EIA2. a recombinant immunoblot assay (RIBA2) was also carried out. In 63 cases, recipients of transfusions which were EIAZ negative or EIA2 reactive were tested for anti-HCV and elevated alanine aminotransferase (ALT) levels 9-1 2 months after transfusion: pretransfusion anti-HCV status of recipients was unknown. Among these multitransfused patients receiving units that were negative by both EIA1 and EIA2, 1/26 (4%) had anti-HCV. Among transfusion recipients of units negative by EIA1, but who received at least one unit reactive by EIA2,4/37 recipients (11%) were anti-HCV reactive (P = 0.59). For the recipients of EIA2 reactive blood, when the donor unit was RIBA2 non-reactive. 0/23 recipients were reactive by anti-HCV. Among the recipients of a RIBA2 indeterminate unit, 1/10 recipients had anti-HCV, but for patients who received at least one RIBA2 reactive unit, 3/4 recipients had anti-HCV (P = 0.0 3). Hence. second-generation anti-HCV testing detected additional units capable of transmitting hepatitis C that were not detected by first-generation testing. However, RIBA2 is a more specific method than EM2 for determining units capable of transmitting HCV.