Blood donor return behavior in South Africa and the United States before and during the COVID-19 pandemic.

BACKGROUND: Studies preceding the COVID-19 pandemic found that slower time-to-return was associated with first-time, deferred, and mobile drive blood donors. How donor return dynamics changed during the COVID-19 pandemic is not well understood. METHODS: We analyzed visits by whole blood donors from 2017 to 2022 in South Africa (SA) and the United States (US) stratified by mobile and fixed environment, first-time and repeat donor status, and pre-COVID19 (before March 2020) and intra-COVID19. We used Kaplan-Meier curves to characterize time-to-return, cumulative incidence functions to analyze switching between donation environments, and Cox proportional hazards models to analyze factors influencing time-to-return. RESULTS: Overall time-to-return was shorter in SA. Pre-COVID19, the proportion of donors returning within a year of becoming eligible was lower for deferred donors in both countries regardless of donation environment and deferral type. Intra-COVID19, the gap between deferred and non-deferred donors widened in the US but narrowed in SA, where efforts to schedule return visits from deferred donors were intensified, particularly for non-hemoglobin-related deferrals. Intra-COVID19, the proportion of donors returning within a year in SA was higher for deferred first-time donors (>81%) than for successful first-time donors (80% at fixed sites; 69% at mobile drives). CONCLUSIONS: The pandemic complicated efforts to recruit new donors and schedule returning visits after completed donations. Concerted efforts to improve time-to-return for deferred donors helped mitigate donation loss in SA during the public health emergency.

An international comparison of HIV prevalence and incidence in blood donors and general population: a BEST Collaborative study.

BACKGROUND AND OBJECTIVES: Efficiency in mitigating HIV transmission risk by transfusion may vary internationally. We compared HIV prevalence and incidence in blood donors across different jurisdictions in relation to those rates in the general population and differences in deferral practices. MATERIALS AND METHODS: Data from 2007 to 2016 were collected in Australia, Brazil (São Paulo), Canada, England, France, Italy, Ireland, Japan, the Netherlands, New Zealand, Norway, Spain (Basque Country), USA (Vitalant) and Wales. For each country/region, the number of HIV antibody-positive donations and nucleic acid testing (NAT)-only-positive donations was broken down according to first-time or repeat donor status, along with the relevant denominators. RESULTS: There is a modest correlation between HIV prevalence among first-time donors and HIV prevalence in the general population. However, rates of HIV-positive donations in repeat donors, a proxy for incidence, do not correlate with incidence rates in the general population. Rates in donors from Italy and Basque Country, where deferral criteria for men having sex with men are less stringent, are higher compared with most other jurisdictions. Rates of NAT-only-positive donations are extremely low and do not differ significantly after adjustment for multiple comparisons. CONCLUSION: Donor HIV rates are only weakly associated with those observed in the general population. Countries with less stringent deferral criteria have higher HIV rates in their donor population, but the rates remain very low.

Use of Blood Donor Screening to Monitor Prevalence of HIV and Hepatitis B and C Viruses, South Africa.

Among 397,640 first-time blood donors screened in South Africa during 2012-2015, HIV prevalence was 1.13%, hepatitis B virus prevalence 0.66%, and hepatitis C virus prevalence 0.03%. Findings of note were a high HIV prevalence in Mpumalanga Province and the near absence of hepatitis C virus nationwide.

A retrospective analysis of false-positive infectious screening results in blood donors.

BACKGROUND: False-positive infectious transfusion screening results remain a challenge with continued loss of both donors and blood products. We sought to identify associations between donor demographic characteristics (age, race, sex, education, first-time donor status) and testing false positive for viruses during routine blood donation screening. In addition the study assessed the prevalence of high-risk behaviors in false-positive donors. STUDY DESIGN AND METHODS: Blood Systems, Inc. donors with allogeneic donations between January 1, 2011, and December 31, 2012, were compared in a case-control study. Those with a false-positive donation for one of four viruses (human immunodeficiency virus [HIV], human T-lymphotropic virus [HTLV], hepatitis B virus [HBV], and hepatitis C virus [HCV]) were included as cases. Those with negative test results were controls. For a subset of cases, infectious risk factors were evaluated. RESULTS: Black race and Hispanic ethnicity were associated with HCV and HTLV false-positive results. Male sex and lower education were associated with HCV false positivity, and age 25 to 44 was associated with HTLV false positivity. First-time donors were more likely to be HCV false positive although less likely to be HBV and HTLV false positive. No significant associations between donor demographics and HIV false positivity were observed. A questionnaire for false-positive donors showed low levels of high-risk behaviors. CONCLUSION: Demographic associations with HCV and HTLV false-positive results overlap with those of true infection. While true infection is unlikely given current testing algorithms and risk factor evaluation, the findings suggest nonrandom association. Further investigation into biologic mechanisms is warranted.

Blood group A and D negativity are associated with symptomatic West Nile virus infection.

BACKGROUND: West Nile virus (WNV) infection is mostly asymptomatic (AS) but 20% of subjects report WNV fever and 1% of patients experience neurologic diseases with higher rates in elderly and immunosuppressed persons. With no treatment and no vaccine to prevent the development of symptomatic (S) infections, it is essential to understand prognostic factors influencing S disease outcome. Host genetic background has been linked to the development of WNV neuroinvasive disease. This study investigates the association between the ABO and D blood group status and WNV disease outcome. STUDY DESIGN AND METHODS: The distribution of blood groups was investigated within a cohort of 374 WNV+ blood donors including 244 AS and 130 S WNV+ blood donors. Logistic regression analyses were used to examine associations between A, B, O, and D blood groups and WNV clinical disease outcome. RESULTS: S WNV+ donors exhibited increased frequencies of blood group A (S 47.6%, AS 36.8%, p = 0.04; odds ratio [OR], 1.56; 95% confidence interval [CI], 1.01-2.40) and D- individuals (S 21.5%, AS 13.1%, p = 0.03; OR, 1.82; 95% CI, 1.04-3.18). CONCLUSION: The findings suggest a genetic susceptibility placing blood group A and D- individuals at risk for the development of S disease outcome after WNV infection.

Outpatient red blood cell transfusion payments among patients on chronic dialysis.

BACKGROUND: Payments for red blood cell (RBC) transfusions are separate from US Medicare bundled payments for dialysis-related services and medications. Our objective was to examine the economic burden for payers when chronic dialysis patients receive outpatient RBC transfusions. METHODS: Using Truven Health MarketScan® data (1/1/02-10/31/10) in this retrospective micro-costing economic analysis, we analyzed data from chronic dialysis patients who underwent at least 1 outpatient RBC transfusion who had at least 6 months of continuous enrollment prior to initial dialysis claim and at least 30 days post-transfusion follow-up. A conceptual model of transfusion-associated resource use based on current literature was employed to estimate outpatient RBC transfusion payments. Total payments per RBC transfusion episode included screening/monitoring (within 3 days), blood acquisition/administration (within 2 days), and associated complications (within 3 days for acute events; up to 45 days for chronic events). RESULTS: A total of 3283 patient transfusion episodes were included; 56.4% were men and 40.9% had Medicare supplemental insurance. Mean (standard deviation [SD]) age was 60.9 (15.0) years, and mean Charlson comorbidity index was 4.3 (2.5). During a mean (SD) follow-up of 495 (474) days, patients had a mean of 2.2 (3.8) outpatient RBC transfusion episodes. Mean/median (SD) total payment per RBC transfusion episode was $854/$427 ($2,060) with 72.1% attributable to blood acquisition and administration payments. Complication payments ranged from mean (SD) $213 ($168) for delayed hemolytic transfusion reaction to $19,466 ($15,424) for congestive heart failure. CONCLUSIONS: Payments for outpatient RBC transfusion episodes were driven by blood acquisition and administration payments. While infrequent, transfusion complications increased payments substantially when they occurred.

Genetic research in the blood bank: acceptability to Northern California donors.

BACKGROUND: Blood banks have large altruistic donor populations and existing infrastructure that make them attractive sites for genetic epidemiologic research, but donors' willingness to participate and the impact on blood donation are unknown. STUDY DESIGN AND METHODS: A total of 2162 blood donors in Northern California responded to a cross-sectional questionnaire in August and September 2007. Participants were asked their likelihood of participation and future blood donation under three different scenarios: identity-linked genetic research, identity-unlinked genetic research, and genetic testing as a service. RESULTS: The majority of blood donors indicated that they would be likely or very likely to participate in identity-linked genetic research (67%) and in identity-unlinked genetic research (54%). While older donors and more frequent donors were more likely to participate in identity-linked research, younger, Caucasian, more educated, and more frequent donors were more likely to participate in identity-unlinked research. Less than 10% of donors indicated they would be less likely to donate blood in the future if genetic research was conducted at blood banks. More than 75% of donors would be interested in genetic testing as an optional service at the blood bank, but more than 20% of donors would be less likely to donate if such a service was offered. CONCLUSION: Overall, we found that the majority of blood donors would be likely to participate in genetic research and that less than 10% would be less inclined to donate if such research was conducted by blood banks.

Minority and foreign-born representation among US blood donors: demographics and donation frequency for 2006.

BACKGROUND: Historically, minority populations have represented only a small proportion of US blood donors, but recent trends in immigration and potential blood shortages emphasize the need for recruitment strategies to increase minority donations. STUDY DESIGN AND METHODS: Donation data from a network of six US blood centers for 2006 were analyzed. Race/ethnicity, country of birth, and educational attainment data were collected specifically for the study and assessed for their influence on donation behavior. Logistic regression was used to determine independent associations with repeat donors status and annual donation frequency. RESULTS: A total of 1,288,998 donations from 729,068 donors were studied; most donors had data on race/ethnicity (97.1%) and country of birth (93.1%). The proportion of minority donors differed by blood center, with African American donors (16%) most common at the Southeastern blood center and Asian (12%), Hispanic (13%), and foreign-born donors (13%) most common at the Northern California blood center. Minority donors and those born in Mexico or Latin America were younger than white donors. Minority and non-US-born donors were less likely than white and US-born donors to be repeat donors (odds ratio [OR], 0.60-0.78), and most were less likely to give two or more annual donations (OR, 0.82-1.11). CONCLUSION: Minority and Mexico/Latin America-born donors represent a younger and often first-time donor population compared to white and US-born donors, but their annual donation frequency was only slightly lower than white and US-born donors. Increasing the retention and donation frequency of minorities will be important for supplementing the blood supply.

Review of current transfusion therapy and blood banking practices.

Transfusion Medicine is a dynamically evolving field. Recent high-quality research has reshaped the paradigms guiding blood transfusion. As increasing evidence supports the benefit of limiting transfusion, guidelines have been developed and disseminated into clinical practice governing optimal transfusion of red cells, platelets, plasma and cryoprecipitate. Concepts ranging from transfusion thresholds to prophylactic use to maximal storage time are addressed in guidelines. Patient blood management programs have developed to implement principles of patient safety through limiting transfusion in clinical practice. Data from National Hemovigilance Surveys showing dramatic declines in blood utilization over the past decade demonstrate the practical uptake of current principles guiding patient safety. In parallel with decreasing use of traditional blood products, the development of new technologies for blood transfusion such as freeze drying and cold storage has accelerated. Approaches to policy decision making to augment blood safety have also changed. Drivers of these changes include a deeper understanding of emerging threats and adverse events based on hemovigilance, and an increasing healthcare system expectation to align blood safety decision making with approaches used in other healthcare disciplines.

Simultaneous estimation of detection sensitivity and absolute copy number from digital PCR serial dilution.

Digital polymerase chain reaction (dPCR) is a refinement of the conventional PCR approach to nucleic acid detection and absolute quantification. Digital PCR works by partitioning a sample of DNA or cDNA into many individual, parallel PCR reactions. Current quantification methods rely on the assumption that the PCR reactions are always able to detect single target molecules. When the assumption does not hold, the copy numbers will be severely underestimated. We developed a novel dPCR quantification method which determines whether the single copy assumption is violated or not by simultaneously estimating the assay sensitivity and the copy numbers using serial dilution data sets. The implemented method is available as an R package "digitalPCR".

Active and passive cigarette smoking and risk of intracranial meningioma.

Motivated by prior studies, we examined associations between cigarette smoking and risk of intracranial meningioma in a population-based case-control study, including 200 cases and 2 controls matched to each case on age and sex. Subjects were asked to recall their history of active and passive cigarette smoking occurring 10 or more years before the date of meningioma surgery. Ever active smoking was associated with an increased risk of meningioma in men (OR = 2.1; 95% CI 1.1-4.2) but not in women (OR = 0.7; 95% CI 0.5-1.1). The statistical interaction by gender was significant (p = 0.01). In men, risk increased with increasing number of cigarettes smoked daily (p for trend = 0.04). In women, the trend was opposite (p for trend = 0.08). Among never active smokers, passive smoking from a spouse was associated with increased risk in both sexes (OR 2.0; 95% CI 1.1-3.5), and risk increased with increasing duration of exposure (p for trend = 0.02). Uncertain is whether these findings reflect a true biological phenomenon or result from chance or uncontrolled confounding.

The association between breast carcinoma and meningioma in women.

BACKGROUND: Published case reports of a possible association between meningioma and breast carcinoma are not uncommon in the literature. Four published analytic studies have addressed this suggested association specifically. Three of these studies reported significant associations, with relative risk estimates mostly between 1.5 and 2.0. The other study reported relative risk point estimates near 1.5, but confidence intervals included 1.0. The current study was a population-based, retrospective cohort analysis that evaluated the risk of subsequent breast carcinoma in women who were diagnosed with meningioma and the risk of subsequent meningioma in women who were diagnosed with breast carcinoma. METHODS: The measure of association is the relative risk and is reported as the standardized incidence ratio (SIR). Using western Washington State cancer registry data and intercensal population estimates for western Washington State, incidence rates of second primary tumor were compared between identified meningioma and breast carcinoma cohorts and the general population for the years 1992-1998. RESULTS: The risk of breast carcinoma after patients were diagnosed with meningioma (SIR) was 1.54 (95% confidence interval [95% CI], 0.77-2.75). The risk of meningioma after patients were diagnosed with breast carcinoma was 1.40 (95% CI, 0.67-2.58), and the risk of meningioma after patients were diagnosed with invasive breast carcinoma was 1.64 (95% CI, 0.79-3.02). In each combination for age groups ages > 50 years, risks were elevated, but the confidence intervals included 1.0. CONCLUSIONS: These results suggest that the risk of meningioma among women who have experienced breast carcinoma and the risk of breast carcinoma among women who have experienced meningioma are elevated moderately. Shared risk factors may account for the relatively week bidirectional associations seen in this and other studies.

Dental X-rays and the risk of intracranial meningioma: a population-based case-control study.

BACKGROUND: Ionizing radiation is a likely cause of intracranial meningioma. The authors determined whether the risk of intracranial meningioma was associated with past dental X-rays-specifically, posterior bitewings, full-mouth series, and lateral cephalometric and panoramic radiographs. METHODS: The authors conducted a population-based case-control study of residents of King, Pierce, and Snohomish counties in western Washington State. Case patients (n = 200) had an incident intracranial meningioma that was confirmed histologically during life between January 1995 and June 1998. The authors used random-digit dialing and Medicare eligibility lists to identify two control subjects to be matched to each case patient based on age and gender. Exposures were determined during an in-person interview. The authors compared self-report and dental records in a subset of study participants. RESULTS: Of the 4 dental X-ray procedures evaluated, only the full-mouth series (specifically, > or = 6 over a lifetime) was associated with a significantly increased risk of meningioma (odds ratio, 2.06; 95% confidence limits, 1.03-4.17). However, evidence for a dose-response relation was lacking (P for trend = 0.33). The risk was elevated with the aggregate number of full-mouth series in 10-year periods from approximately 15-40 years before diagnosis, with significant elevations in the 10-year periods beginning 22-30 years before diagnosis. The risks in these analyses were even greater when only women were considered. CONCLUSIONS: Dental X-rays involving full-mouth series performed 15-40 years ago, when radiation exposure from full-mouth series was much greater than it is now, were associated with an increased risk of meningioma. The authors did not observe an increased risk with bitewings, lateral cephalometric, and panoramic radiographs.