Screening potential blood donors at risk for human immunodeficiency virus

A Systematic Review of Interventions Used to Increase Blood Donor Compliance with Deferral Criteria

Background and Objectives

Pre-donation screening of potential blood donors is critical for ensuring the safety of the donor blood supply, and donor deferral as a result of risk factors is practised worldwide. This systematic review was conducted in the context of an expert review convened by the Australian Red Cross Lifeblood in 2013 to consider Lifeblood's injecting drug use (IDU)-related policies and aimed to identify studies assessing interventions to improve compliance with deferral criteria in blood donation settings.

Materials and Methods

MEDLINE/PubMed, OVID Medline, OVID Embase, LILACS, and the Cochrane Library (CENTRAL and DARE) databases were searched for studies conducted within blood donation settings that examined interventions to increase blood donor compliance with deferral criteria. Observational and experimental studies from all geographical areas were considered.

Results

Ten studies were identified that tested at least one intervention to improve blood donor compliance with deferral criteria, including computerized interviews or questionnaires, direct and indirect oral questioning, educational materials, and a combination of a tickbox questionnaire and a personal donor interview. High-quality evidence from a single study was provided for the effectiveness of a computerized interview in improving detection of HIV risk behaviour. Low-quality evidence for the effectiveness of computerized interviews was provided by 3 additional studies. Two studies reported a moderate effect of direct questioning in increasing donor deferral, but the quality of the evidence was low.

Conclusion

This review identified several interventions to improve donor compliance that have been tested in blood donation settings and provided evidence for the effectiveness of computerized interviews in improving detection of risk factors.

Characteristics of post donation information donors and comparison with appropriately deferred donors

BACKGROUND

Post donation information (PDI) is the most frequently reported biological product deviation (BPD) related to donor suitability and the health history screening process. PDI occurs when a deferrable health history known by the donor is not disclosed, but is subsequently disclosed at a future donation.

STUDY DESIGN AND METHODS

PDI and appropriately deferred (AD) donors were identified at six US blood centers from July 1, 2006, to June 30, 2007. PDI and AD donors were categorized according to travel, medical, blood disease or exposure, and high-risk-sexual and high-risk-nonsexual deferrals. Information was obtained from BPD reports and blood center records. Predictors of PDI were identified using an adjusted logistic regression model controlling for select characteristics.

RESULTS

There were 2059 PDI and 36,512 AD donors. PDI donors were significantly more likely to be male, older, and more educated than AD donors. Medical and high-risk-sexual PDI donors were more likely to have more than six intervening donations before disclosure of deferrable history. PDI donors with a deferral reason due to high-risk behaviors (both sexual and nonsexual) were 2.3 and 2.6 times more likely to be PDI than the reference group (travel PDI donors).

CONCLUSIONS

No previous studies have described the characteristics of PDI donors or examined how PDI donors are different from AD donors for the same deferral reasons. We found that PDIs are more likely in older, male donors with higher levels of education when compared to AD donors.

Preventing transfusion-transmitted HIV infection in Latin America and the Caribbean: issues associated with blood donor interviews and sex between men

BACKGROUND

Blood-borne transmission is the most efficient route for acquiring HIV infection, particularly through transfusion. Availability of noninfectious blood units for hemotherapy is a necessary condition for efficient functioning of health services. They have the obligation to ensure that the blood supply is safe, which includes interviewing potential donors to ascertain whether they might be at risk of being HIV infected. The interview procedures demand that blood services staff inquire potential blood donors about sexual practices associated to HIV transmission. Assumptions and misconceptions may unnecessary exclude adequate donors.

METHODS

Review of published and unpublished country reports in Latin America regarding blood safety and deferral criteria related to same sexual behavior among males.

RESULTS

An analysis of criteria for deferral of potential blood donors shows inconsistencies that may impact the necessary safe blood supply.

CONCLUSIONS

The blood donor deferral criteria should be revised according to relevant epidemiological evidence and social legitimacy. Personnel in blood banks and hemotherapy services should be educated to conduct appropriate interviews for accepting or deferring potential donors. Potential donors and the public should be knowledgeable for them to understand the reasons why some individuals may be deferred. Health authorities should work to reduce the stigma associated with HIV, prioritize building strong and meaningful partnerships with civil society, and engage diverse sectors in the national AIDS response.

Reducing the risk of transfusion-transmissible viral infection through blood donor selection: the Australian experience 2000 through 2006

BACKGROUND

Selection of voluntary donors who are at low risk of transfusion-transmissible viral infection (TTVI) is central in maintaining the safety of the blood supply. Evaluation of its effectiveness and the dynamics of the process may offer opportunities to further improve transfusion safety.

STUDY DESIGN AND METHODS

The impact of donor selection on prevalence of TTVI was analyzed in all allogeneic donations in Australia between July 2000 and June 2006 by interviewing donors found to have a TTVI. The presence and disclosure of infective risks was reassessed.

RESULTS

A total of 6.3 million donations were tested; of these, 1,449 (0.02%) were repeat-reactive for a TTVI and were discarded. This comprised 605 (42%) positive for the presence of hepatitis B, 818 (56%) positive for the presence of hepatitis C, 18 (1%) positive for the presence of human immunodeficiency virus, and 20 (1%) positive for the presence of human T-cell lymphotropic virus-I and/or -II (HTLV-I/II). This prevalence was 50 to 350 times lower than in the Australian population. In 1,158 cases (80%), an infective risk was identified; 509 donors (44%) had more than one. The most common identified were country of birth and parental ethnicity (n = 682, 26% of risks), tattoos and/or piercings (n = 448, 18%), and intravenous drug use (n = 302, 12%). In 302 cases (21%) disclosure at predonation screening would have resulted in deferral. Factors influencing nondisclosure included temporal remoteness and perceptions that laboratory testing rendered disclosure unnecessary.

CONCLUSION

These findings affirm the effectiveness of current stringent donor selection criteria in reducing the residual risk of TTVI. Ongoing donor education regarding the importance of risk disclosure is required.

The Canadian Blood Donor Health Assessment Questionnaire: Lessons From History, Application of Cognitive Science Principles, and Recommendations for Change

Over the last 20 years, the Canadian Blood Services' (CBS) Donor Health Assessment Questionnaire (DHAQ), used to screen prospective blood donors to determine their eligibility, has grown in complexity and length. Its growth is inextricably linked to the evolution of the environment within which CBS operates from unregulated collection and distribution of labile blood products to a fully regulated environment and to the need to satisfy both Health Canada and US Food and Drug Administration (FDA) requirements. Within this context, the development of the CBS DHAQ has been characterized by addition of questions and items without any periodic reevaluation of the need for retaining existing questions and/or items. In this review, we apply principles from cognitive science relating to how people think when answering questionnaires to the situation of blood donors completing the DHAQ. We show that some items that were added at different times in separate questions, for reasons that were historically relevant, could be now asked more simply with a single question. The historical development of the DHAQ, resulting in the condensing of many items into lists, the use of complex wording, and the sheer number of items included in the questionnaire make accurate retrieval of information from the donor's memory difficult. Thus, we believe that redesigning the DHAQ will improve the quality and accuracy of the donors' answers to screening questions.

Face-to-face interviewing in predonation screening: lack of effect on detected human immunodeficiency virus and hepatitis C virus infections

BACKGROUND

Predonation screening has become more elaborate over the years, while human immunodeficiency virus (HIV)- and hepatitis C virus (HCV)-positive donations have declined. The impact of face-to-face interviewing and of the format of the Donor Health Assessment Questionnaire (DHAQ) have not been evaluated.

STUDY DESIGN AND METHODS

Canadian Blood Services DHAQ records between 1990 and 2004 were examined, and changes in them were tracked. The proportion of first-time donors permanently deferred for HIV or HCV risk, and the HIV and HCV rates per 100,000 donations, were calculated annually. Time-series analysis was used to determine whether major predonation screening changes had any effect on the HIV or HCV rates or permanent deferrals.

RESULTS

In 1992, receiving money or drugs for sex was added to the DHAQ; otherwise, the content of high-risk questions changed little between 1990 and 2004. In 1997, the method of administration of the DHAQ changed from donor-completed to face-to-face interviewing for high-risk questions. Permanent deferrals for HIV or HCV risk factors and HIV and HCV rates in first-time donors decreased over this period. The HIV rates were close to 0 before 1997, whereas HCV rates decreased steadily through 2004. There was no interruption in rates in 1997 when the method of administration changed.

CONCLUSION

Face-to-face interviewing for high-risk questions had no effect on HIV or HCV rates in first-time donations over 15 years of observation (during the latter 8 of which face-to-face interviewing was in place), and it did not increase permanent deferrals for HIV or HCV risk factors.

Risk-behavior reporting by blood donors with an automated telephone system

BACKGROUND

Donor risk-behavior assessment is important for blood safety. Few evaluations of automated telephone systems for eliciting risk exposure among voluntary blood donors have been reported.

STUDY DESIGN AND METHODS

A modified risk-behavior questionnaire was presented after donation via an automated telephone polling system to 805 of 15,092 Hong Kong Chinese voluntary blood donors. Risk-behavior rates were compared to those of all other donors (14,287) simultaneously completing the questionnaire in a pencil-and-paper format.

RESULTS

The telephone group included proportionally more women (46.3% vs. 44.9%), previous donors (93.3% vs. 83.6%), and sexually inactive donors (66.5% vs. 71.2%) with lower educational achievement (60.7% vs. 54.5%). The telephone group demonstrated fewer missing data (mean 1.3%, range 0.4%-3.1% vs. mean 9.8%, range 8.0%-14.2%) and more complete demographic detailing, probably accounting for the demographic differences. The telephone group reported higher prevalence rates of needle or syringe sharing (1.5% vs. 0.3%), homosexual and/or bisexual intercourse (4.1% vs. 1.3%), knowing or suspecting that partner had intercourse with another during past year (12.4% vs. 8.5%), and future intention to use blood donation as a means to test for human immunodeficiency virus (HIV; 19.1% vs. 13.7%). There was no difference in knowledge of the HIV window period or proportions visiting or using condoms with commercial sex workers between telephone and pencil-and-paper groups.

CONCLUSION

This survey with automated telephone screening of potential blood donors revealed increased reporting of risk exposure relative to commonly used paper-and-pencil methods. This raises questions of possible underreporting of risk among blood donors screened by paper questionnaire and perhaps face-to-face interview.

[Residual risk of human immunodeficiency virus infection in blood banks. Impact of screening with nucleic acid tests]

In most developed countries of the world, the risk of human immunodeficiency virus (HIV) transmission by transfusion of blood and blood products is extraordinarily small. This level of blood safety has been accomplished by successive refinement in donor screening and testing procedures for the detection and inactivation of different infectious agents in blood and blood products. In USA, the recent introduction of nucleic acid techniques (NAT) in blood banks for the detection of HIV and hepatitis C virus (HCV) has meant a great advance in decreasing the residual risk of HIV/HCV transmission by blood transfusion. In general, after analyzing the first four-years of NATs experience in US blood banks, the introduction of NATs in European blood centers could be considered, since this technique has shown improved output to detect donations from individuals in the very early stages of infection before detectable serologic response has been developed.

Do blood donors read and understand screening educational materials?

BACKGROUND

Blood donors with high-risk behaviors may not self-defer because they failed to read or understand the screening educational materials.

STUDY DESIGN AND METHODS

In 1993, a total of 34,726 allogeneic donors responded to an anonymous mail survey of 50,162 donors that inquired about demographics, donor status, amount of the donor educational materials read, new HIV knowledge gained, and donors' opinions on the length and difficulty of materials.

RESULTS

Although 78 percent reported reading all materials, only 32 percent indicated reading carefully; 34 percent learned new information about HIV and 95 percent perceived the materials as easy to understand. First-time donors were more likely to read carefully (OR, 7.9) and gain more HIV knowledge from the materials (OR, 1.9) than repeat donors. Minority, less educated, screening test-reactive, and HIV test-seeking donors reported reading the materials more carefully and learning more about HIV than their respective counterparts. Donors with less education, those with reactive screening tests, those seeking HIV test results, and those not reporting a risk behavior were more likely to find the materials difficult to understand.

CONCLUSION

Most donors reported skimming and not having difficulty understanding the educational materials. Some donors may be aware that they should not donate or are failing to assimilate the information in the materials. Methods to present information more clearly and concisely are clearly needed. However, some high-risk donors may still continue donating no matter how improved the educational materials are.

Comparison of deferral rates using a computerized versus written blood donor questionnaire: a randomized, cross-over study [ISRCTN84429599]

BACKGROUND

Self-administered computer-assisted blood donor screening strategies may elicit more accurate responses and improve the screening process.

METHODS

Randomized crossover trial comparing responses to questions on a computerized hand-held tool (HealthQuiz, or HQ), to responses on the standard written instrument (Donor Health Assessment Questionnaire, or DHAQ). Randomly selected donors at 133 blood donation clinics in the area of Hamilton, Canada participated from 1995 to 1996. Donors were randomized to complete either the HQ or the DHAQ first, followed by the other instrument. In addition to responses of 'yes' and 'no' on both questionnaires, the HQ provided a response option of 'not sure'. The primary outcome was the number of additional donors deferred by the HQ.

RESULTS

A total of 1239 donors participated. Seventy-one potential donors were deferred as a result of responses to the questionnaires; 56.3% (40/71) were deferred by the DHAQ, and an additional 43.7% (31/71) were deferred due to risks identified by the HQ but not by the DHAQ. Fourteen donors self-deferred; 11 indicated on the HQ that they should not donate blood on that day but did not use the confidential self-exclusion option on the DHAQ, and three used the self-exclusion option on the DHAQ but did not indicate that they should not donate blood on the HQ. The HQ identified a blood contact or risk factor for HIV/AIDS or sexually transmitted infection that was not identified by the DHAQ in 0.1% to 2.7% of donors.

CONCLUSION

A self-administered computerized questionnaire may increase risk reporting by blood donors.

Knowledge of HIV/AIDS transmission and screening in United States blood donors

BACKGROUND

Increased knowledge of HIV transmission and behavioral and test screening may encourage high-risk blood donors to self-defer.

STUDY DESIGN AND METHODS

Knowledge of HIV transmission and screening and the association with demographics, screening test reactivity, and unreported deferrable risks (UDRs) was assessed by a 1998 anonymous mail survey sent to 92,581 blood donors, of whom 57 percent responded. Groups were compared by using weighted chi-square tests and logistic regression analysis.

RESULTS

Four percent of the donors thought that it was very likely or somewhat likely for a person to contract HIV from donating blood, and 20 percent perceived a similar risk from blood transfusion. Only 60 percent of the donors knew that the available screening tests may not detect a recent infection. Thirty-seven percent either did not know or felt it was acceptable to donate blood to obtain HIV testing. Those most likely to answer knowledge questions incorrectly were more likely to have a higher prevalence of test reactivity or UDRs and to be <or=25 years old, members of a minority, less educated, non-US-born, or first-time donors.

CONCLUSION

Innovative ways to increase donor understanding of the implications of risk behaviors and the limitations of current screening procedures should be developed. They might prevent high-risk individuals from donating blood.

Validation of selected donor-screening questions: structure, content, and comprehension

BACKGROUND

Donor questioning is an integral component of blood safety, designed to identify and interdict donors considered to be at elevated risk of transfusion-transmissible infection. Questions are frequently added to this screening procedure, but they are rarely evaluated for comprehension.

STUDY DESIGN AND METHODS

Seven American Red Cross blood donor history questions were selected for evaluation. Focus groups were conducted using individuals from high school/college, church, business, and other sources, who had never donated blood. Both sexes and various age and racial groups were represented. The donation process and regulatory requirements or guidelines were explained. Participants were asked to consider 1) content, 2) clarity 3) likelihood of asking for more information, 4) suggestions for improvement, and 5) how a need for clarifying information would best be met.

RESULTS

Constructive, helpful, and consistent comments obtained might be utilized in revising questions.

CONCLUSION

Focus group discussions can be useful in providing guidance for developing screening questions that can be easily understood.

[Risk behavior among blood donors: efficacy of a new questionnaire]

The clinical selection of volunteers for blood donation is essential to reduce the risk of viral transmission by blood transfusion. The aim of this study was to evaluate a new questionnaire for a pre-donation medical interview. This questionnaire was developed by transfusion practitioners, epidemiologists and professional investigators, and focused on risk behaviors of blood donors and their partners. Five blood banks in the French Ile-de-France region (around Paris), participated in the study from May 1995 to January 1996. All participating doctors were specifically trained by professional investigators. The sex and the age of donors, the type of collection, the duration of interviews and the reasons for exclusion from donation were recorded. The results were compared to those of a prior study dealing with a sample of 15,000 donors presenting the same characteristics, whose blood was taken of at the same collection sites in 1993. Of the 1,527 volunteers donating blood, 14% were interviewed in fixed centers and 86% by moving teams (38% in firms, 22% in towns, 13% in civil service facilities, 13% in school or academic centers). For 15.9% of the volunteers, this was the first donation (range: 7.3% in fixed centers to 41.5% in school and academic centers). The mean duration of the interview was 11 min (10 min for volunteers included, 14 min for donors excluded from donation). It decreased from 14 min at the beginning of the study to 10 min by the end of the study. The percentage of donors excluded for risk behavior (3.7% in 1995-96 vs 1.5% in 1993, P < 0.001), or medical reasons (12.2% in 1995-96 vs 8.4%, in 1993, P < 0.001) was significantly greater in 1995-96 than in 1993 (15.9% vs 9.9%, P < 0.001). In 1995-96, 35.0% of exclusions for risk behavior were related to male homosexuality, multiple partners or the risk behavior of the partner vs 12% in 1993 (P < 0.001). The risk of exclusion was 5.5 times higher for donors not living in a couple. The results obtained demonstrated the value of this new approach to the medical interview.

Risk factors for acquisition of hepatitis C virus infection in blood donors: results of a case-control study

BACKGROUND & AIMS

Few studies have explored risk factors predicting hepatitis C virus (HCV) infection in blood donors; their results are contradictory. The aim of this study was to evaluate the association between HCV infection and various risk factors in Canadian volunteer blood donors.

METHODS

Four transfusion centers were involved in this case-control study. A total of 267 confirmed anti-HCV-positive blood donors were interviewed along with 1068 seronegative blood donors matched for sex, age, donation site, and date. Information was collected using a structured telephone interview. The main outcome measures were odds ratios (ORs) and 95% confidence intervals (CIs) for various risk factors from univariate and multivariate analyses using conditional logistic regression.

RESULTS

By univariate analysis, 23 variables were associated with anti-HCV positivity. In the final multivariate analysis, only 5 factors remained independently predictive of HCV infection: previous intravenous drug use (OR, 127.5; 95% CI, 26.0-625.0), having lived in a prison or juvenile detention center (56.1; 11.4-275.7), previous blood transfusion (10.5; 4.7-23.2), sexual contact with an intravenous drug user (6.9; 3.1-15.2), and tattooing (5.7; 2.5-13).

CONCLUSIONS

Most blood donors acquire infection by percutaneous exposure to contaminated blood. A role for sexual transmission is suggested by this study.

Interactions between science, government and media on selection and testing of donors

The international media attention to "bad blood" has fueled governmental action in countries around the world. Donor selection criteria continue to expand, focusing most recently on the possibility of exclusion due to intranasal cocaine use and, in the US, due to incarceration for more than 72 hours. As newer methods of testing evolve, more deferrals will occur due to improved testing. An emerging area of concern is the non-standardized notification of donors who are ineligible to donate and lack of a centralized listing of such deferred donors. Because of the consequences to recipients, improvements in both donor questioning and testing are necessary. Further studies are needed to understand and improve these processes.

[Infection risk and efficacy of clinical selection techniques for volunteer blood donors]

One of the objectives of predonation selection is to exclude blood donors with possible infection. Our aim was to evaluate the efficacy of the different blood donor selection techniques. The approach chosen for this review of literature was the best evidence synthesis. A bibliographic search was carried out to identify all articles on the subject published between 1986 and 1996 which presented quantitative results of evaluation. Only nine relevant studies were selected. These referred to self exclusion before interview, health history interview and confidential deferral after donation. None of the articles evaluated the physical examination. The results suggested an efficacy for self exclusion before interview. One study considered the blood donor selection and compared various ways of combining self exclusion before interview, health history interview and confidential deferral after donation. No combination emerged as more effective than the others. This analysis shows that the efficacy of predonation blood donor selection applied to transfusion transmitted infections has not been evaluated adequately. The different techniques of blood donor selection must be considered as public health actions and hence evaluated according to a rigorous methodology using valid criteria.

Flow cytometric immunofluorescence assay for detection of antibodies to human immunodeficiency virus type 1 using insoluble precursor forms of recombinant polyproteins as carriers and antigens

A new serological assay, the recombinant flow cytometric immunofluorescence assay (r-FIFA), was developed for the early detection of human immunodeficiency virus type 1 (HIV-1) antibodies by using recombinant insoluble forms of HIV-1 Gag-p45, Gag-gp41 chimeric protein, gp160, Po197 polyprotein as antigens and autologous carriers through flow cytometry. These recombinant proteins were expressed in insect cells by a baculovirus expression system. Eight anti-HIV-1 seroconversion panels, a low-titer anti-HIV-1 panel from Boston Biomedica Inc. (BBI), and three HIV-1 seroconversion specimens from the Provincial Health Laboratory of Ontario, Toronto, Ontario, Canada (PHL), were tested and analyzed by r-FIFA. In sensitivity comparisons between r-FIFA and tests licensed by the U.S. Food and Drug Administration, which were used to test all of the HIV-1 panels from BBI, detection of HIV-1 antibody by r-FIFA was on average greater than 20 days earlier than that by enzyme immunoassay. The sensitivity of r-FIFA has permitted the detection of HIV-1-specific immunoglobulin G (IgG), IgM, and IgA antibodies during seroconversion. A kinetic analysis of HIV-1 antibody production of r-FIFA has shown that either IgG or IgM, or both, can be detected, depending on the phase and type of the immune response in the HIV-1-infected individual. Both primary and secondary immune responses were observed during this period. The r-FIFA results suggest that implementation of r-FIFA may significantly reduce the "window" period from the time of infection to the time of seroconversion, with earlier detection of antibodies after initial infection. This would also make it possible for us to understand the immune response and the precise mechanisms of immunopathogenesis in the early period of HIV-1 infection.

Blood transfusion in beta thalassaemia major

Conventional treatment of beta thalassaemia major is based on regular blood transfusion from early childhood. Maximum effectiveness of transfusion therapy depends on the following. (1) Availability of safe blood. Donation programmes should aim at retaining repeat donors, who carry decreased risk of transmitting blood-borne infections. Donors should be screened with laboratory tests performed to the highest possible standard of quality. Selection of safe donors can be improved by the adoption of questionnaires containing direct questions on risk factors for transfusion transmissible infections. (2) Use of good quality red blood cells, which should be leucodepleted, preferably by filtration, that can be carried out at the bedside. (3) Regular evaluation of blood transfusion indices, including mean level of haemoglobin maintained, annual blood requirement, daily haemoglobin fall, mean transfusion interval, transfusion reaction rate. This can be assisted by the use of a computerized patient record. (4) Maintenance of a permanent record of the patient's blood group genotype (including at least Rh, Kell, Kidd and Duffy systems) and any red cell antibodies that develop. This is mandatory to ensure optimal survival of transfused red cells. (5) Continuous monitoring of transfusion transmissible infections. (6) Vaccination against hepatitis B of all suitable patients. (7) Intensive iron chelation. This should be done by regular subcutaneous administration of desferrioxamine B. Oral chelators, which are currently under laboratory and clinical evaluation, are not yet available for general use.

Viral contamination of blood components and approaches for reduction of infectivity

Currently, the United States blood supply offers a relatively low risk of viral infection. This is a result of careful selection of donors and extensive laboratory testing using sensitive procedures. Epidemiologic data show that there is some room for improvement in donor selection, but such improvements cannot be expected to entirely eliminate the collection of blood from infectious donors. Similarly, increased numbers of tests, along with improvements in the analytic sensitivity of these tests, may further reduce risk, but again, complete safety cannot be assured. Consequently, there is continuing interest in the development of safe and effective procedures for viral inactivation of single donor blood components. In order to establish appropriate expectations for such inactivation procedures, it is necessary to understand the titers and distributions of viral contaminants in blood components. Viruses may variously occur free in the plasma, as replicative forms in actively infected leukocytes, as integrated proviral DNA and perhaps, nonspecifically associated with cellular surfaces.

Demographic characteristics and prevalence of serologic markers among donors who use the confidential unit exclusion process: the Retrovirus Epidemiology Donor Study

BACKGROUND

Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial.

STUDY DESIGN AND METHODS

Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups.

RESULTS

Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent.

CONCLUSION

The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a "random process," as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect.

Donor deferral registries

In the last half of this century, donor deferral registries have grown in size, scope, and importance for blood collection organizations and regulatory agencies. This has occurred despite the lack of direct evidence that, when used with all other methods, they contribute meaningfully to the safety of the blood supply. Any decrease in the perceived benefit of deferral registries has been a result of the introduction of a panoply of serological testing of donor blood intended to detect transmissible disease. As the sensitivity of serological testing improves, the relative merit of the subjective methods used for blood supply safety diminish. Although computers have become a mainstay in the management of deferral registries, accurate and consistent donor identification, good manual systems, and quality control of data bases are key features to their successful management. As with the other subjective methods used in maintaining blood supply safety, techniques must be developed to determine the value of the many features of donor deferral registries. Efforts must be made to simplify these processes and focus on those elements that provide important contributions to blood supply safety. Today, donor deferral registries are major activities in most blood centers and are believed to play a significant role in blood supply safety. It is time for their role to be carefully reexamined.

Gift or good? A contemporary examination of the voluntary and commercial aspects of blood donation

The safety and ethical aspects of blood donation are examined in the light of current legislation and practice. The advantages and disadvantages of voluntary and paid donation are looked at in view of recent data concerning risk factors in various potential donor groups. It is concluded that voluntary, non-remunerated blood donation remains the safest and most ethical means of securing the blood supply.