Human T-lymphotropic virus antibody screening of blood donors: rates of false-positive results and evaluation of a potential donor reentry algorithm

BACKGROUND: Blood donor screening with enzyme immunoassays (EIAs) for antibodies to human T‐lymphotropic virus (HTLV)‐I, and later to HTLV‐I/II, has led to the unnecessary deferral of tens of thousands of individuals. The licensure of the Abbott PRISM HTLV‐I/HTLV‐II chemiluminescent immunoassay (ChLIA) may permit the reinstatement of historically deferred donors. STUDY DESIGN AND METHODS: The efficacy of a reentry algorithm involving a follow‐up sample from EIA‐deferred donors testing HTLV‐I/II ChLIA nonreactive was evaluated using 386 serologic confirmed‐positive samples archived since the inception of anti‐HTLV donor screening. Reactivity of the 386 samples by the ChLIA, when coupled with the package insert sensitivity data, may be used to demonstrate efficacy of the reentry algorithm. Donor incidence was also examined from 2008 through 2009 to evaluate changes to the existing HTLV screening policy. RESULTS: From January 1, 1995, to April 28, 2008, a total of 64,052 donors to the American Red Cross were deferred solely because of HTLV EIA false positivity, representing more than 130,000 US donors. HTLV ChLIA identified 386 confirmed‐positive donations from 386 randomly selected donors representing reactivity to both the bioMérieux and the Abbott HTLV‐I/II EIAs (95% confidence interval [CI], 99.2%‐100%); both EIAs have since been discontinued. This is comparable to the detection of 843 of 843 confirmed‐positive samples during the ChLIA clinical trials (95% CI, 99.48%‐100%). Incident HTLV infections occurred primarily among female repeat donors during 2008 throughout 2009. CONCLUSIONS: Donors testing falsely positive by historic EIAs since 1988 should be considered for reinstatement if a contemporary sample tests ChLIA nonreactive. Changes to the existing screening algorithm seem unlikely since new HTLV infections were detected among repeat donors.     

Analysis of voluntary blood donors with biologic false reactivity on chemiluminescent immunoassays and implications for donor management

BACKGROUND: Biologic false-reactive (BFR) results in blood donors are problematic due to both component loss and donor-management issues. This report analyzes the results of a longitudinal study of BFR donors and the implications for donor management. STUDY DESIGN AND METHODS: Donors who gave BFR results on HBsAg, HIV-1/HIV-2, HCV, or HTLV-I/HTLV/II chemiluminescent immunoassays (ChLIAs) (PRISM, Abbott) between May 1997 to March 1999 were analyzed. Donors were followed up for up to three donations after an index BFR episode. In addition, results of any negative donations before the index BFR result but within the study period were included in the analysis. RESULTS: For donors who gave an index BFR result on the HBsAg ChLIA, 14.3 percent remained BFR at subsequent donations, whereas for the anti-HIV-1/HIV-2, anti-HCV, and anti-HTLV-I/HTLV-II ChLIAs, the figures were 66.0, 77.4, and 71.6 percent, respectively. For donors who gave a second BFR result, the percentage who remained BFR at subsequent donations was 75.0, 80.6, 84.6, and 74.5 percent for the four assays, respectively. The rate at which negative repeat donors became BFR during the study period was 0.02, 0.07, 0.12, and 0.02 percent for the HBsAg, anti-HIV-1/HIV-2, anti-HCV, and anti-HTLV-I/HTLV-II assays, respectively. CONCLUSIONS: Our results indicate that donors who give an index BFR result on the ChLIAs (PRISM, Abbott) should be allowed to continue donating because most donors with a HBsAg BFR result were negative at subsequent donations, and between 22.6 and 34.0 percent of those with BFR results on the HIV-1/HIV-2, HCV, or HTLV-I/HTLV-II assays gave subsequent negative donations. However, donors who give a second BFR result should be counseled and deferred because they were very unlikely to give subsequent negative results.     

Incidence rates of viral infections among repeat donors:are frequent donors safer?

BACKGROUND: Incidence rates (IRs) for viral infections may vary with the frequency of donation among repeat, community, whole-blood (WB) donors, with IRs thought to be lower among donors with higher frequency of donation. STUDY DESIGN AND METHODS: IRs for HIV, HTLV, HCV, and HBV infection were stratified by frequency of donation among 868,403 repeat WB donors who gave approximately 4 million donations at five United States blood centers from 1991 through 96. All donors had given at least 2 donations during those years, with the first donation being nonreactive on confirmatory testing. Frequency of donation was measured in three ways: by the number of donations per year; at the time of donation, by the number of donations given within the preceding 2-year period; and by the number of donations given from 1991 through 1993. RESULTS: The IRs for HIV, HCV, and HBV infection did not appear to differ among donors with lower or higher numbers of donation per year. However, the IR for HTLV infection decreased as the number of donations per year increased (p = 0.0004). IRs for all viral markers remained stable, regardless of the number of donations given within the 2-year period before the donation. Although IRs for HIV, HTLV, and HCV infection did not vary by the number of donations given in 1991 through 1993, the IR for HBV infection appeared to be lower in donors who gave more donations in that period (p = 0.01). CONCLUSION: These findings do not provide evidence of a lower IR for transfusion-transmissible viral infections among repeat WB donors who give more frequently. Abbreviated screening histories for frequent repeat donors might not be advisable.     

The impact of temporary deferral due to low hemoglobin: future return,time to return,and frequency of subsequent donation

BACKGROUND: This study investigated the effects of a 6‐month deferral due to low hemoglobin (Hb) on the subsequent donation patterns of Australian whole blood donors. STUDY DESIGN AND METHODS: The study was a retrospective cohort study of the donation patterns of all whole blood donors deferred for low Hb during a 2‐month period compared with donors who were not deferred. Donations 3 years after eligibility to give blood were recorded. Analysis of proportion returning, time to return, and frequency of donation was performed using logistic regression, survival analysis, and negative binomial regression. RESULTS: Among first‐time donors, 20.9% of low Hb–deferred donors returned during the follow‐up period versus 69.9% of those not deferred. Among repeat donors, 64.0% of deferred donors returned versus 91.0% of those not deferred. Temporary deferral delayed time to first return (p < 0.001), reduced frequency of donation (2.4 donations per donor before deferral compared to 1.1 per donor in first year of follow‐up), and increased the likelihood of dropping out in later years of follow‐up. However, if a donor returned promptly once eligible and gave more donations in the first year, the negative impact on future donation patterns was diminished. High frequency of attendance before deferral was the strongest predictor of time to return and future donation frequency. CONCLUSION: Deferral for low Hb had a strong effect on first‐time and repeat donors. This study highlights the influence of strong donation habits on return after deferral and the importance of encouraging donors to return promptly once eligible.     

Analysis of sample‐to‐cutoff ratios on chemiluminescent immunoassays used for blood donor screening highlights the need for serologic confirmatory testing

BACKGROUND: High sample‐to‐cutoff (s/co) ratios on hepatitis C virus antibody (anti‐HCV) screening immunoassays (IAs) are indicative of confirmed‐positive results and, according to some reports, can be used to determine anti‐HCV status without the need for confirmatory testing. The purpose of this study was to determine whether s/co ratios on hepatitis B surface antigen (HBsAg), antibody to human immunodeficiency virus Types 1 and 2 (anti‐HIV‐1/2), anti‐HCV, and antibody to human T‐lymphotropic virus Types I and II (anti‐HTLV‐I/II) chemiluminescent immunoassays (ChLIAs) can be used to discriminate between biologic false‐reactive (BFR) and confirmed‐positive results. STUDY DESIGN AND METHODS: In a blood donor population the s/co ratio distributions for BFR and confirmed‐positive results were compared for the Abbott PRISM HBsAg, HIV O Plus, HCV, and HTLV‐I/II ChLIAs to determine the extent of overlap between the two distributions for each assay. RESULTS: The s/co ratio distributions for BFR and confirmed results overlapped in the range of 10.00 to 60.00, 1.00 to 6.00, 3.00 to 15.00, and 1.00 to 100.00 for the PRISM HIV O Plus, HCV, HTLV‐I/II, and HBsAg assays, respectively. CONCLUSION: Although high s/co ratios were predictive of confirmed‐positive results in all four assays, a number of confirmed‐positive samples gave low values while some biologic false‐positive samples showed high values. As the s/co ratio distributions for BFR and confirmed‐positive results overlapped for all four PRISM assays, this study highlights the importance of serologic confirmatory testing and the need for caution when using screening IA results to assign a final donor status.     

Analysis of Chinese donors' return behavior

BACKGROUND: It is important to understand donor return behavior. Converting first‐time donors to become repeat donors is essential for maintaining an adequate blood supply. STUDY DESIGN AND METHODS: Characteristics of 241,552 whole blood (WB) donations from first‐time and repeat donors who donated in 2008 at the five blood centers in China were compared. A subset of 54,394 WB donors who donated between January 1 and March 31, 2008, were analyzed for their return behavior in 2008 after the index donation using logistic regression. RESULTS: Of all donations, 64% were from first‐time donors. Donors with self‐reported previous donations tended to be male, older, and married; donated larger volume (≥300 mL); and were heavier in weight. Among donors who donated from January to March 2008, 14% returned for subsequent WB donations by the end of 2008. The number of previous donations and blood collection location were the two strongest predictors for making subsequent donations. Donors with one, two to three, and more than three previous donations were 3.7, 5.7, and 11.0 times more likely to return than first‐time donors. Those who donated in a blood collection vehicle were four times more likely to return than those who donated at a blood center. Being female, younger, and of a lower education level (middle school or less) were positively associated with subsequent return blood donation during the follow‐up period observed in this study. CONCLUSION: Most of the Chinese blood supply is from first‐time donors. Strategies aimed at encouraging current donors to become repeat donors are needed.     

Quantifying losses to the donated blood supply due to donor deferral and miscollection

BACKGROUND: Donors are deferred for multiple reasons. Losses related to disease marker rates are well established. Donor and donation losses for other reasons, however, have not been extensively quantified. STUDY DESIGN AND METHODS: To quantify these losses, three data sets from the Blood Centers of the Pacific were combined, permitting detailed analysis of year 2000 allogeneic whole-blood donations. RESULTS: During 2000, 13.6 percent of 116,165 persons who presented for donation were deferred at presentation. Short-term deferral accounted for 68.5 percent (hematocrit was most common at 60%); long-term deferral accounted for 21 percent (travel to a malarial area and tattoo or other nonintravenous drug use needle exposure were most common at 59 and 29%, respectively); and multiple-year or permanent deferral accounted for 10.5 percent (UK travel [variant Creutzfeldt-Jakob disease] risk and emigration from a malarial area were most common at 38 and 11%, respectively). Disease-marker-reactive donations represented 0.9 percent of donor outcomes. The prevalence of deferral and also miscollection (under- and overweight units) varied by age, sex, and first-time versus repeat donor status. Overall, miscollection led to a loss of 3.8 percent of 100,141 collections, ranging from 1.9 percent in repeat male donors 40 to 54 years of age to 10.7 percent in first-time female donors 16 to 24 years of age. CONCLUSION: Loss of units from both first-time and repeat donors due to temporary deferral and loss of units from miscollection are more common events than losses due to disease marker testing. Some of these losses may be avoidable and could increase the blood supply without having to recruit new donors.     

A comparison of human immunodeficiency virus,hepatitis C virus,hepatitis B virus,and human T‐lymphotropic virus marker rates for directed versus volunteer blood donations to the American Red Cross during 2005 to 2010

BACKGROUND: At most US blood centers, patients may still opt to choose specific donors to give blood for their anticipated transfusion needs. However, there is little evidence of improved safety with directed donation when compared to volunteer donation. STUDY DESIGN AND METHODS: The percentage of directed donations made to the American Red Cross (ARC) from 1995 to 2010 was determined. Infectious disease marker rates for human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), and human T‐lymphotropic virus (HTLV) were calculated for volunteer and directed donations made from 2005 to 2010. Odds ratios (ORs) were calculated to compare marker‐positive rates of directed donations to volunteer donations. RESULTS: The percentage of donations from directed donors declined from 1.6% in 1995 to 0.12% in 2010. From 2005 to 2010, the ARC collected 38,894,782 volunteer and 69,869 directed donations. Rates of HIV, HCV, HBV, and HTLV for volunteer donations were 2.9, 32.2, 12.4, and 2.5 per 100,000 donations, respectively; for directed, the rates were 7.2, 93.0, 40.1, and 18.6 per 100,000. After demographics and first‐time or repeat status were adjusted for, corresponding ORs of viral marker positivity in directed versus volunteer donations were not significant for HIV, HBV, or HTLV and significant for HCV (OR, 0.7; 95% confidence interval, 0.50‐0.90). CONCLUSIONS: Directed donations have declined by 92% at the ARC since 1995, but have higher viral marker rates than volunteer donations. The difference can be explained in part by the effects of first‐time or repeat status of the donors. Patients considering directed donation should be appropriately counseled about the potential risks.     

Development and validation of a prediction model for low hemoglobin deferral in a large cohort of whole blood donors

BACKGROUND: Each year, approximately 5% of the invited blood donors is eventually deferred from donation because of low hemoglobin (Hb) levels. Estimating the risk of Hb deferral in blood donors can be helpful in the management of the donation program. We developed and validated a prediction model for Hb deferral in whole blood donors, separately for men and women. STUDY DESIGN AND METHODS: Data from a Dutch prospective cohort of 220,946 whole blood donors were used to identify predictors for Hb deferral using multivariable logistic regression analyses. Validity of the prediction models was assessed with a cross‐validation. RESULTS: A total of 12,865 donors (5.8%) were deferred because of a low Hb level. The strongest predictors of Hb deferral were Hb level measured at the previous visit, age, seasonality, difference in Hb levels between the previous two visits, time since the previous visit, deferral at the previous visit, and the total number of whole blood donations in the past 2 years for both men and women. The prediction models had an area under the receiver operating characteristic curve of 0.89 for men and 0.84 for women. Cross‐validation showed similar results and good calibration. CONCLUSION: Using a limited number of easy‐to‐measure characteristics enables a good prediction of Hb deferral risk in whole blood donors. The prediction models may guide the decision which donors to invite for a next donation and for which donors the invitation should be postponed. Potentially, this could decrease the number of Hb deferrals in blood donors.     

Hemoglobin and iron indices in nonanemic premenopausal blood donors predict future deferral from whole blood donation

BACKGROUND: Iron deficiency anemia is an important reason for blood donor deferral. We prospectively determined whether screening donors with hemoglobin (Hb) and iron indices before donation can predict subsequent deferral due to anemia. STUDY DESIGN AND METHODS: We recruited premenopausal, eligible (nonanemic) female donors. Hb, ferritin, soluble transferrin receptor (sTfR), and hepcidin were measured, and the sTfR/(log)ferritin (sTfR‐F) index was calculated. After 6 months, the donor database was reviewed and whether donors had returned and undergone successful donation was recorded. RESULTS: Of donors, 59 of 261(22.6%) were iron depleted (ferritin < 15 ng/mL). Iron‐depleted donors had donated more often in the previous year, were younger, and had lower Hb. After a minimum of 6 months, 145 eligible donors had returned; of these 10 (6.9%) were deferred for anemia. Donors who developed anemia had significantly lower Hb, ferritin, and hepcidin and higher sTfR and sTfR‐F at baseline. The area under the receiver operating characteristic curve for Hb as a predictor of deferral was 0.86, and for ferritin was 0.88. Hb of less than 130 g/L and ferritin of less than 10 ng/mL combined had sensitivity 80% and specificity 96% in predicting deferral. CONCLUSION: Screening with Hb and iron indices enables prediction of donors at risk of subsequent anemia and who would most benefit from prevention strategies.     

Limited effectiveness of donor deferral registries for transfusion-transmitted disease markers

BACKGROUND: Donor deferral registries (DDRs) detect repeat donations by previously deferred donors and prevent their release. The utility of DDRs has not been objectively demonstrated. STUDY DESIGN AND METHODS: A total of 10.2 million first-time donors to the American Red Cross from 1995 through 2002 were reviewed to identify donors deferred by screening tests for human immunodeficiency virus (HIV; 0.19% of donors), hepatitis C virus (HCV; 0.55%), and hepatitis B virus (HBV; 0.13%). All repeat-reactive (RR) donors were deferred despite confirmatory testing. Donors were notified and counseled about their test results and deferral. Their subsequent donation behavior was assessed. RESULTS: A total of 414 HIV-deferred donors (2.1%), 471 HCV-deferred donors (0.8%, p < 0.001 vs. HIV and HBV), and 222 HBV-deferred donors (1.6%, p < 0.01 vs. HIV) returned to donate despite their deferred status. For all three tests, confirmed-positive donors were less likely to return. Of donors originally confirmed positive, only 7 returning donors were negative by screening (thus the repeat donation interdicted from distribution by the DDR): 0 HIV RR donors, 2 of 36,092 HCV RR donors, and 5 of 8,404 HBV RR donors. Review of the laboratory results for the HCV donors and one HBV donor was consistent with originally false-positive confirmation tests. The four other HBV confirmed-positive donors were anti-hepatitis B core antigen-positive on their subsequent donation, which was discarded despite the DDR. CONCLUSION: Of 10.2 million donors, the DDR did not prevent the release of any potentially dangerous blood component due to inappropriate return of donors deferred for HIV, HCV, and HBV tests. The effectiveness of DDRs should be evaluated for other deferrals.     

The effect of short-term, temporary deferral on future blood donation

BACKGROUND: Most blood donor deferrals are temporary and short-term. The effect of short-term, temporary deferral (STTD) on blood donor return rates and subsequent blood donations is an important issue. STUDY DESIGN AND METHODS: Donors given STTDs during the first 3 months of 1993 were computer-matched with nondeferred donors on the basis of age, sex, and donation date. Computer records were evaluated during the next 4.25 years (4/93-6/97) to determine donor return rates and subsequent blood donations. RESULTS: The most common reasons STTD were low hemoglobin (46%), colds and/or sore throats (19%), and elevated temperature (10%). Nondeferred donors were 29 percent more likely than donors with STTD to return over the next 4.25 years (80% vs. 62%), and nondeferred donors donated 81 percent more whole blood units (13,798 vs. 7,615) over the same period. CONCLUSION: The study showed that STTD have a very negative impact on blood donor return rates and subsequent blood donations. Actions to alleviate these negative effects are indicated.     

Donor understanding and attitudes about current and potential deferral criteria for high-risk sexual behavior

BACKGROUND: Few donor criteria are as contentious as the deferral of men who have had sex with men (MSM). We performed an anonymous donor survey to determine attitudes toward current screening and the feasibility and acceptability of adoption of alternate donor criteria for MSM. STUDY DESIGN AND METHODS: Donors who had successfully donated to Canadian Blood Services were randomly mailed an anonymous questionnaire several weeks after donation; there were 40,000 donors sampled, evenly split between first‐time and repeat donors. RESULTS: The response rate was 45.5%. The vast majority of donors found the current screening questions and clinic environment acceptable. Attention to clinic educational materials was poor. A total of 53% felt that the MSM criteria should be changed; many were supportive of criteria based on specific behaviors rather than a period of abstinence. Gender‐neutral questions such as number of sexual partners would result in deferral of large numbers of donors. CONCLUSION: Many donors would support a change in MSM deferral policy. Implementation of strategies based on donor attention to additional material would be challenging. Universal use of simple gender‐neutral questions would result in very high donor loss and are therefore not an acceptable option. The acceptability and feasibility of various screening approaches should be explored further with both donors and advocacy groups.     

The introduction of anti-HTLV testing of blood donations and the risk of transfusion-transmitted HTLV, UK: 2002–2006

summary .  The objectives of the study were to describe the introduction of testing blood donations for antibodies to human T-cell lymphotropic virus (anti-HTLV) and to determine the risk of HTLV potentially infectious donations entering the UK blood supply. The rationale for testing was based on (i) evidence of transmission through transfusion in the UK, (ii) the serious nature of HTLV I-associated morbidity and (iii) evidence of infection in UK blood donors. From mid-2002, all blood donations made at UK blood centres were tested in pooled samples using Abbott-Murex HTLV I/II GE 80/81 enzyme immunoassay (EIA). Surveillance data were used to calculate the incidence and prevalence of anti-HTLV and derive estimates of risk. Between August 2002 and December 2006, 106 donations were confirmed positive for anti-HTLV (95 anti-HTLV I and 11 anti-HTLV II). Prevalence was 10-fold higher among donations from new donors than repeat (4·0 and 0·42 per 100 000 donations), and only one repeat donor had evidence of seroconversion. The risk of an HTLV I potentially infectious donation entering the UK blood supply was estimated at 0·11 per million donations (95% confidence interval 0·06 to 0·18). The current very low observed incidence and prevalence among blood donors reflect the very low estimated risk of an HTLV I-positive donation entering the UK blood supply. A change in either the epidemiology of HTLV in UK blood donors or the length of the window period of the test should prompt further review of the risk and a reassessment of anti-HTLV testing in the UK.     

Demographic correlates of low hemoglobin deferral among prospective whole blood donors

BACKGROUND: Approximately 10% of attempted blood donations are not allowed because of low hemoglobin (Hb) deferral. STUDY DESIGN AND METHODS: Low Hb deferrals were tracked in more 715,000 whole blood donors at six blood centers across the United States. A multivariable logistic regression model was developed to comprehensively assess demographic correlates for low Hb deferral. RESULTS: Demographic factors significantly associated with low Hb deferral include female sex (11 times greater odds than males), increasing age in men (men over 80 have 29 times greater odds than men under 20), African American race (2‐2.5 times greater odds than Caucasians), Hispanic ethnicity in women (1.29 times greater odds than Caucasian women), and weight in men (men under 124 pounds have 2.5 times greater odds than men over 200 pounds). Interestingly, increasing donation frequency is associated with decreased odds for low Hb deferral (women with one donation in the previous 12 months have two times greater odds than those with six donations). CONCLUSIONS: Low Hb deferral is associated with female sex, older age, African American race/ethnicity, and lower body weight in men. An inverse association with donation frequency suggests a selection bias in favor of donors able to give more frequently. These data provide useful information that can be utilized to manage blood donors to limit low Hb deferrals and assist in policy decisions such as changing the Hb cutoff or permissible frequency of donation. They also generate hypotheses for new research of the causes of anemia in defined groups of donors.     

Implementation of concurrent red blood cell and platelet collection by apheresis in a university haemapheresis unit

The present study analyses the number of concurrently collected red blood cell (RBC) units in plateletpheresis donors and the reasons why donors were deferred from multicomponent collection. Donors undergoing concurrent collection of RBCs and platelets (PLTs) were retrospectively evaluated for haemoglobin values and the reasons for deferral over a period of 1 year. A total of 404 RBC units were concurrently collected with PLTs. An average of 1.8 RBC units per year was collected from each donor. The baseline haemoglobin values were almost equal for the RBC donations. An RBC unit was not collected in 190 aphereses. Most frequent reasons for the noncollection of an RBC product were a donation interval of less than 3 months (20.5%), haematoma and blood flow problems (18.9%) and low pre-haemoglobin values (17.4%). Donor eligibility has to be taken into account to optimize concurrent RBC collection in plateletpheresis.     

HTLV antibody screening using mini-pools

At the present time, the UK blood transfusion services do not screen blood donations for anti-HTLV. This presentation describes a pilot study to ascertain the feasibility of HTLV antibody screening using mini-pools and also provides an estimate of HTLV prevalence within our donor population in Scotland and Northern Ireland. The Abbott/Murex HTLV I/II GE80/81 ELISA was selected for the trial. Thirty confirmed HTLV positive library samples were tested at various dilutions and five were shown to be nonreactive at a dilution of 1:100. Residues of mini-pools (of up to 95 individual donations) prepared for HCV NAT testing were tested with the Abbott/Murex GE80/81 assay. Of 6666 mini-pools (equivalent to 570 609 donations) tested, six were repeatedly reactive. All six mini-pools were confirmed HTLV antibody positive by line immunoassay. Four were confirmed to be HTLV-I positive, one HTLV-II positive and one HTLV positive (unable to type). Dilutions (1:100) of the five HTLV "nonreactive" positive samples were included in each test plate and used to determine a grey-zone cut-off. Using this grey-zone system an additional six (0.09%) mini-pool samples gave repeatedly reactive grey-zone results, none of which were confirmed. The minimum Scottish/Irish HTLV donor prevalence was shown to be 1:95 000.     

Demographic,laboratory, and operational variables that influence short‐ and long‐term plateletpheresis yields

We studied the demographic, laboratory, and operational parameters that might influence individual, as well as average, plateletpheresis yields. Multivariate linear regression analyses showed that 25.4% and 11.6% of variability, among males and females, respectively, in individual yields was explained by the platelet count prior to that donation and 55% of the variation in mean platelet yields (PYs) was explained by the pre‐first donation platelet count, the first donation PY and the body mass index (BMI). Logistic regression analysis showed that donors with first donation PYs higher, compared to those with lower yields, than the median of all mean PYs were more likely to be relatively high platelet yielders over the long term. A statistically significant, although clinically insignificant, decline in predonation platelet counts is seen in all donors regardless of the total number of donations or interdonation interval. Donors with high pre‐first donation platelet counts, first donation yields, and BMI are likely to be consistent good platelet yielders. J. Clin. Apheresis 27:247–254, 2012. © 2012 Wiley Periodicals, Inc.     

Blood donation screening for hepatitis B virus markers in the era of nucleic acid testing: are all tests of value?

BACKGROUND: The American Red Cross implemented hepatitis B virus (HBV) minipool (MP)‐nucleic acid testing (NAT) in June 2009, in addition to existing tests for hepatitis B surface antigen (HBsAg) and antibodies to hepatitis B core antigen (anti‐HBc). The value of all three tests was evaluated. STUDY DESIGN AND METHODS: HBsAg, anti‐HBc, and HBV DNA (Ultrio MP‐NAT, Gen‐Probe/Novartis) donation results were analyzed during a 12‐month period (July 1, 2009‐June 30, 2010). Additional testing by individual‐donation (ID) polymerase chain reaction (PCR) to confirm donor infection was performed when any HBV screening test was reactive or positive, except in the case of HBsAg neutralization‐positive, anti‐HBc–reactive samples. Numbers of blood donations identified as reactive or positive versus nonreactive or negative were compared. RESULTS: Of about 6.5 million donations, 699 were defined as from HBV‐infected donors, of which 64% (444) were reactive for all three markers. More than 99% (697) had reactivity to one or both serologic tests with 68% (477) showing reactivity by MP‐NAT. Only two donations were DNA‐positive, seronegative NAT‐yield donations (1 per 3.23 million), fewer than expected (p = 0.0075). Among MP‐NAT–reactive donors, only small numbers represented early infection (2 or 0.4% with negative serology and 10 or 2.1% who were HBsAg confirmed positive, anti‐HBc nonreactive). Of the 142 occult HBV‐infected donors, 85% were MP‐NAT nonreactive requiring ID‐PCR for detection (121 or 54.5% of all MP‐NAT nonreactives vs. 21 or 4.4% of all MP‐NAT reactives). CONCLUSIONS: The HBV DNA–positive yield rate from MP‐NAT was lower than expected, likely representing the rarity of such findings even in very large studies. With the implementation of HBV MP‐NAT, the value of maintaining anti‐HBc for the detection of low‐level HBV DNA–positive donors was confirmed; however, HBsAg screening showed no blood safety value.     

Interdonation intervals and patterns of return among blood donors in Brazil

BACKGROUND: In Brazil, most donations come from repeat donors, but there are little data on return behavior of donors. STUDY DESIGN AND METHODS: Donors who made at least one whole blood donation in 2007 were followed for 2 years using a large multicenter research database. Donation frequency, interdonation intervals, and their association with donor demographics, status, and type of donation were examined among three large blood centers in Brazil, two in the southeast and one in the northeast. RESULTS: In 2007, of 306,770 allogeneic donations, 38.9% came from 95,127 first‐time donors and 61.1% from 149,664 repeat donors. Through December 31, 2009, a total of 28.1% of first‐time donors and 56.5% of repeat donors had donated again. Overall, the median interdonation interval was approximately 6 months. Among men it was 182 and 171 days for first‐time and repeat donors, and among women, 212 and 200 days. Predictors of return behavior among first‐time donors were male sex (odds ratio [OR], 1.17; 95% confidence interval [CI], 1.13‐1.20), community donation (OR, 2.26; 95% CI, 2.20‐2.33), and age 24 years or less (OR, 0.62‐0.89 for donors ≥25 years). Among repeat donors predictors were male sex (OR, 1.35; 95% CI, 1.32‐1.39), age 35 years or more (OR, 1.08‐1.18 vs. ≤24 years), and community donation (OR, 2.39; 95% CI, 2.33‐2.44). Differences in return by geographic region were evident with higher return rates in the northeast of Brazil. CONCLUSION: These data highlight the need to develop improved communication strategies for first‐time and replacement donors to convert them into repeat community donors.