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Background: In Canada, as many as 24% of mothers are deferred from cord blood (CB) donation due to risk factors for Zika virus (ZIKV). However, the ZIKV epidemic has waned considerably since 2016, and there has not been any report of ZIKV transmission by CB transplantation, which questions this policy. Thus, we performed an analysis of the risk of introducing ZIKV in the CB supply maintained by Héma-Québec (HQ) and Canadian Blood Services (CBS)., Study Design and Methods: This simulation considered the following parameters: the risk of travel exposure in a high-risk ZIKV country, the duration of travel, the daily risk of acquiring ZIKV in a high-risk country, the probability of materno-fetal ZIKV transmission, the probability of asymptomatic fetal viremia, and the probability of sexual transmission. A hundred million Monte Carlo simulations were run., Results: In the most-likely scenario (probability of traveling to a high-risk ZIKV country while pregnant = 0.178), the risk was estimated at 0.9 ZIKV-positive donations per million donations (95% confidence interval [CI] = 0.4-1.6)-or one every 868 years at HQ and one every 453 years at CBS. In the pessimistic model (probability of traveling to a high-risk ZIKV country while pregnant = 0.240), the risk was estimated at 1.2 ZIKV-positive donations per million donations (95% CI = 0.6-2.1)-or one every 644 years at HQ and one every 340 years at CBS., Discussion: We conclude that the risk of introducing ZIKV in the Canadian CB supply is too small to justify maintaining the current policy., (© 2024 AABB.)

Background: Hepatitis B core antibody (anti-HBc) screening has been implemented in many blood establishments to help prevent transmission of hepatitis B virus (HBV), including from donors with occult HBV infection (OBI). We review HBV screening algorithms across blood establishments globally and their potential effectiveness in reducing transmission risk., Materials and Methods: A questionnaire on HBV screening and follow-up strategies was distributed to members of the International Society of Blood Transfusion working party on transfusion-transmitted infectious diseases. Screening data from 2022 were assimilated and analyzed., Results: A total of 30 unique responses were received from 25 countries. Sixteen respondents screened all donations for anti-HBc, with 14 also screening all donations for HBV DNA. Anti-HBc prevalence was 0.42% in all blood donors and 1.19% in new donors in low-endemic countries; however, only 44% of respondents performed additional anti-HBc testing to exclude false reactivity. 0.68% of anti-HBc positive, HBsAg-negative donors had detectable HBV DNA. Ten respondents did universal HBV DNA screening without anti-HBc, whereas four respondents did not screen for either. Deferral strategies for anti-HBc positive donors were highly variable. One transfusion-transmission from an anti-HBc negative donor was reported., Discussion: Anti-HBc screening identifies donors with OBI but also results in the unnecessary deferral of a significant number of donors with resolved HBV infection and donors with false-reactive anti-HBc results. Whilst confirmation of anti-HBc results could be improved to reduce donor deferral, transmission risks associated with anti-HBc negative OBI donors must be considered. In high-endemic areas, highly sensitive HBV DNA testing is required to identify infectious donors., (© 2024 The Author(s). Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

Background and Objectives: Data provided from blood donors have contributed to the understanding of public health epidemiology and policy decisions. A recent example was during the severe acute respiratory syndrome-related coronavirus (SARS-CoV-2) pandemic when blood services monitored the seroprevalence in blood donors. Based on this experience, blood services have the opportunity to expand their role and participate in public health surveillance and research. The aim of this report is to share available resources to assist blood services in this area., Materials and Methods: The Surveillance, Risk Assessment and Policy (SRAP) Sub-group of the International Society of Blood Transfusion (ISBT) Transfusion Transmitted Infectious Diseases (TTID) Working Party developed a Public Health Research Toolkit to assist blood services and researchers interested in expanding their role in public health research., Results: The ISBT Public Health Research Toolkit provides resources for what blood services can offer to public health, examples of donor research studies, the utility of donor data and website links to public health agencies. The toolkit includes a customizable template for those interested in establishing and managing a biobank., Conclusion: The ISBT Public Health Research Toolkit includes resources to increase the recognition of the role blood donors can play in public health and to help blood services gain commitment and funding from various agencies for new research and surveillance., (© 2024 The Author(s). Vox Sanguinis published by John Wiley & Sons Ltd on behalf of International Society of Blood Transfusion.)

Background and Objectives: There is a growing infectious syphilis outbreak in Western Canada. Although blood donors are screened for syphilis risks, some blood donors will still be confirmed test-positive for syphilis. This study compares the characteristics of confirmed test-positive syphilis donations in both Western Canada and Eastern Canada, November 2022-August 2023., Materials and Methods: Donors were defined as Western or Eastern Canadian. Blood donations were tested for syphilis using the PK-TP assay (Beckman Coulter PK7300 Automated Microplate System). Confirmatory Treponema pallidum particle agglutination (TPPA) and rapid plasma reagin (RPR) assays were performed by one of two reference laboratories. An RPR titre ≥1:8 was used as a proxy for possible infectious syphilis., Results: Rates of laboratory-confirmed syphilis were higher in Western (n = 43, 13.4/100,000 donations) versus Eastern donors (n = 19, 4.7/100,000 donations; Fisher's exact test, two-sided, p ≤ 0.0001). Most syphilis confirmations were in first-time donors (Western Canada n = 31/43, 72.1%, Eastern Canada 12/19, 63.2%)., Conclusion: Although rates of laboratory-confirmed syphilis were higher in Western versus Eastern donors, Western donors did not have higher rates of infectious syphilis. Further studies might assess whether donors with laboratory-confirmed syphilis understood pre-donation screening questions or were completely unaware of a past infection., (© 2024 International Society of Blood Transfusion.)

Background: Combining pathogen reduction technology (PRT) with blood screening may alleviate concerns over the risk of transfusion-transmitted infections (TTI) and support changes in blood donor selection to potentially increase blood availability. This study aimed to estimate the residual risk of human immunodeficiency virus (HIV), hepatitis B virus (HBV), and hepatitis C virus (HCV) transfusion-transmission in Canada after implementing PRT, while eliminating deferrals for sexual risk behaviors., Study Design and Methods: A probabilistic approach that combined Bayesian networks with Monte Carlo simulations was used to estimate the risk of transfusing HIV-, HBV-, or HCV-contaminated blood components. Different scenarios were considered to compare the current residual risk after PRT implementation, with and without donor deferral criteria for sexual risk behaviors. Donor profiles and blood component outcomes were simulated based on a literature review including the prevalence and incidence of HIV, HBV, and HCV in the Canadian blood donor population; the use of current blood screening assays; and HIV, HBV, and HCV blood donor viral loads., Results: In the universal PRT scenario (i.e., with PRT/without deferral criteria), the estimated risks of HIV, HBV, and HCV transmission were significantly lower than those in the currently observed scenario (i.e., without PRT/with deferral criteria)., Conclusions: This risk model suggests that PRT for platelets and plasma (and eventually for RBCs when available) significantly reduces the residual risks of HIV, HBV and HCV transfusion-transmission and could enable the removal of blood donor deferral criteria for sexual risk behaviors., (© 2024 AABB.)

Background and Objectives: Trypanosoma cruzi is the etiologic agent of Chagas disease (CD), an anthropozoonosis from the American continent that progresses from an acute phase to an indeterminate phase, followed by a chronic symptomatic phase in around 30% of patients. In countries where T. cruzi is not endemic, many blood transfusion services test blood donors who have stayed in an endemic country ('at-risk stay')-even if they do not present with other risk factors. However, the efficiency of this approach has been questioned., Materials and Methods: On 18 September 2023, a worldwide survey was distributed among employees of blood transfusion services. The questions mainly pertained to CD's endemicity in the blood services' region, the current testing policy for T. cruzi and the number of confirmed positive results among donors with a prior at-risk stay alone (i.e., without other risk factors for T. cruzi infection)., Results: Twenty-six recipients completed the survey. Of the 22 (84.6%) blood services that operated in a non-endemic region, 9 (42.9%) tested donors for T. cruzi, including 8 (88.9%) that considered the travel history or the duration of the stay (alone) in their testing algorithm ('study blood services'). Over 93 years of observation among all study blood services, 2 donations from donors with an at-risk stay alone and 299 from those with other risk factors were confirmed positive for T. cruzi., Conclusion: The study findings question the utility of testing blood donors who have stayed in an endemic country without other risk factors., (© 2024 International Society of Blood Transfusion.)

Background: Hepatitis C is a blood-borne infection with the hepatitis C virus (HCV) that can progress to cirrhosis and liver cancer. About 70% (50-80%) of infections become chronic and exhibit anti-HCV and HCV nucleic acid (NAT) positivity. Direct acting oral pan genotypic antiviral treatment became available in 2014 and was free for most Canadians in 2018. Clinical screening for HCV infection is risk-based. About 1% of Canadians have been infected with HCV, with 0.5% chronically infected (about 25% unaware) disproportionately impacting marginalized groups. Blood donors are in good health, are deferred for risks such as injection drug use and can provide insight into the low-risk undiagnosed population. Here we describe HCV epidemiology in first-time blood donors over 28 years of monitoring., Methods: All first-time blood donors in all Canadian provinces except Quebec (1993 to 2021) were analyzed. All blood donations were tested for HCV antibodies (anti-HCV) and since late 1999 also HCV NAT. A case-control study was also included. All HCV positive donors (cases) since 2005 and HCV negative donors (1:4 ratio controls) matched for age, sex and location were invited to complete a risk factor interview. Separate logistic regression models for anti-HCV positivity and chronic HCV assessed the association between age cohort, sex, region and neighbourhood material deprivation and ethnocultural concentration., Case: control data were analysed by logistic regression., Results: There were 2,334,238 donors from 1993 to 2021 included. Prevalence for anti-HCV was 0.33% (0.30,0.37) in 1993 and 0.07% (0.05,0.09) in 2021 (p < 0.0001). In 2021 0.03% (0.01,0.04) had chronic HCV. Predictors for both anti-HCV positivity and chronic HCV were similar, for chronic HCV were male sex (OR 1.8, 1.6,2.1), birth between 1945 and 1975 (OR 7.1, 5.9,8.5), living in the western provinces (OR 1.4, 1.2,1.7) and living in material deprived (OR 2.7, 2.1,3.5) and more ethnocultural concentrated neighbourhoods (OR 1.8, 1.3,2.5). There were 318 (35.4%) of chronic HCV positive and 1272 (39.6%) of controls who participated in case control interviews. The strongest risks for acquisition were injection drug use (OR 96.9, 22.3,420.3) and birth in a high prevalence country (OR 24.5, 11.2,53.6)., Conclusions: Blood donors have 16 times lower HCV prevalence then the general population. Donors largely mirror population trends and highlight the ongoing prevalence of untreated infections in groups without obvious risks for acquisition missed by risk-based patient screening., (© 2024. The Author(s).)

Background and Objectives: The process of selecting blood donors is crucial for keeping the health of donors and ensuring the safety of the blood supply. However, it may create unpleasant feeling in those who are deferred. In this study, we aim to explore the return rates of Iranian deferred donors in comparison with eligible donors., Materials and Methods: The study included all whole blood donors referred between March 2017 and March 2018, who experienced temporary deferral for any reason. Donors who successfully donated blood during this period were also part of the study. Participants were followed up until their next donation attempt, spanning 4.8 years after initial inclusion. Then odds of return and median return time for both deferred and eligible donors were calculated., Results: From 993,824 volunteers, 733,153 (73.77%) were eligible and 192,332 (19.35%) temporary deferred. The return rate in the eligible and deferred donors was 74.77% vs. 51.77%, respectively (OR:2.78; 99%CI: 2.71-2.81). Odds of return among deferred regular (OR = 7.02, 99%CI:6.64-7.42), men (OR: 2.57, 99%CI:2.45-2.69), and over 45 years (OR: 1.15, 99% CI: 1.09-1.20), was higher than first-time, women, and younger donors. The median return time for eligible and deferred donors was 315 (99%CI: 313-316) and 1,467(99%CI: 1,412-1,524) days, respectively., Conclusion: This study revealed the negative effect of deferral on the return rate, that led to a 23% reduction in the return of deferred donors. Avoiding unnecessary deferral through adherence to the standard operating procedure of donor selection and effective counselling which clarifies the purpose of deferral and encourages them to return after the deferral period ends are recommended., (Copyright © 2024 Société française de transfusion sanguine (SFTS). Published by Elsevier Masson SAS. All rights reserved.)

Objectives: Estimate HTLV-1/2 (human T-cell lymphotropic viruses) prevalence in Canadian blood donors and the association of demographic variables with infection and their corresponding risk factors., Methods: First-time blood donors in all Canadian provinces (except Quebec) from 1990 to 2022 were included. Blood samples were tested for HTLV-1/2 by enzyme-linked immunoassay, confirmed by Western blot. Multivariable logistic regression with year, age group, sex, region, neighbourhood material deprivation, and ethnocultural composition indices predicted HTLV-1/2. Since 2005, all HTLV-1/2-positive donors (cases) were invited to participate in a risk factor interview, and 4 non-positive donors (controls per case) were matched for age, sex, and region. Case-control predictors of HTLV-1/2 were analyzed using logistic regression., Results: There were 3,085,554 first-time donors from 1990 to 2022. HTLV-1/2 prevalence remained low (12 per 100,000 in 2022, 95% CI 6.4-23.5). The odds ratios predicting HTLV-1/2 were higher in females (2.0, 95% CI 1.5-2.6), older age groups (50 + ; 6.3, 95% CI 4.3-9.2), British Columbia and Ontario, those materially deprived (1.9, 95% CI 1.2-2.9), and those in ethnocultural neighbourhoods (7.5, 95% CI 3.2-17.3). Most HTLV-1/2 in Ontario was HTLV-1, whereas in British Columbia half were HTLV-2. Forty-three of 149 (28.8%) cases and 172 of 413 (41.6%) controls completed an interview. The strongest predictor of HTLV-1/2 in case-control analysis was birth in a high-prevalence country (OR 39.8, 95% CI 7.8-204.3) but about 50% of HTLV-1 and 90% of HTLV-2 were Canadian-born., Conclusion: HTLV-1/2 prevalence is low in blood donors. High-prevalence country of birth accounts for about half of HTLV-1; HTLV-2 positives are usually Canadian-born. HTLV-1/2 transmission likely occurs overseas and within Canada., (© 2024. The Author(s) under exclusive license to The Canadian Public Health Association.)

Background and Objectives: Nucleic acid-amplification testing (NAT) is used for screening blood donations/donors for blood-borne viruses. We reviewed global viral NAT characteristics and NAT-yield confirmatory testing used by blood operators., Materials and Methods: NAT characteristics and NAT-yield confirmatory testing used during 2019 was surveyed internationally by the International Society of Blood Transfusion Working Party Transfusion-Transmitted Infectious Diseases. Reported characteristics are presented herein., Results: NAT was mainly performed under government mandate. Human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) NAT was performed on all donors and donation types, while selective testing was reported for West Nile virus, hepatitis E virus (HEV), and Zika virus. Individual donation NAT was used for HIV, HCV and HBV by ~50% of responders, while HEV was screened in mini-pools by 83% of responders performing HEV NAT. Confirmatory testing for NAT-yield samples was generally performed by NAT on a sample from the same donation or by NAT and serology on samples from the same donation and a follow-up sample., Conclusion: In the last decade, there has been a trend towards use of smaller pool sizes or individual donation NAT. We captured characteristics of NAT internationally in 2019 and provide insights into confirmatory testing approaches used for NAT-yields, potentially benefitting blood operators seeking to implement NAT., (© 2024 The Authors. Vox Sanguinis published by John Wiley & Sons Ltd on behalf of International Society of Blood Transfusion.)

Background: The two Canadian blood suppliers, Canadian Blood Services and Héma-Québec, removed the time-based deferral for men who have sex with men and adopted criteria assessing sexual risk behaviors. We report the impact of these changes on the safety and adequacy of the Canadian blood supply., Study Design and Methods: Since 2022, all donors are asked if (1) they have had a new partner and (2) more than one sexual partner in the last 3 months. Donors answering yes to either question are asked if they had anal sex in the last 3 months; if yes, they are deferred for 3 months. We followed HIV rates for the 18 months before and 14 (Héma-Québec) or 18 months (Canadian Blood Services) post-implementation and interviewed HIV-positive whole blood donors. We assessed the number and characteristics of whole blood donors answering yes to the two first questions with or without deferral., Results: There were four HIV-positive donations out of 1,492,355 donations pre-implementation and four out of 1,447,772 post-implementation (0.27/100,000 vs. 0.28/100,000, p = 1.00). Post-implementation, one HIV-positive donor was non-compliant with multiple criteria, no risk factors were identified in the others. 3.2% of donors answered yes to questions (1) and/or (2); 0.17% were deferred for a new partner and/or more than one partner and anal sex. Deferral rates were highest in first time, younger donors, and similar in males and females., Conclusion: Implementation of sexual risk behavior donor screening resulted in unchanged HIV rates to date and a manageable deferral rate., (© 2024 AABB.)

Background and Objectives: In Canada, plasma sent for fractionation is tested for both parvovirus B19 (B19V) and hepatitis A virus (HAV). This study compared positivity rates of B19 and HAV nucleic acid tests (NATs) in Canadian plasma samples for the pre-COVID-19 restriction era (2015 to end of February 2020 [Q1] 2020) and the post-COVID-19 restriction era., Materials and Methods: Pooled EDTA plasma specimens were tested within 24 months of blood draw using the Procleix Panther System (Grifols Diagnostic Solutions Inc, San Diego, CA, USA) for B19V and HAV detection. Reactive pools were resolved by individual specimen testing., Results: Between 1 January 2015, and 31 March 2022, 3,928,619 specimens from Canadian plasma donors were tested for B19V. For the same period, 3,922,954 specimens were tested for HAV. To account for a lag in specimen testing for up to 24 months, the data were divided into: (1) a pre-pandemic period (1 January 2015-31 March 2020; B19V tested n = 2,412,701, B19V NAT-positive n = 240 [0.01%], HAV tested n = 2,407,036, HAV NAT-positive n = 26 [0.001%]); (2) a two-year mixed-impact period (1 April 2020-31 March 2022; B19V tested n = 968,250, B19V NAT-positive n = 14 [0.001%], HAV tested n = 968,250, HAV NAT-positive n = 2 [0.0002%]); and (3) a pandemic-impact period (1 April 2022-31 March, 2023; B19V tested n = 597,668, B19V NAT-positive n = 3 [0.0005%], HAV tested n = 597,668, HAV NAT-positive n = 1 [0.0002%])., Conclusion: The percentage of B19V- and HAV-positive donations was significantly reduced from the pre-pandemic period to the pandemic-impact period., (© 2024 International Society of Blood Transfusion.)

Background: In Canada's largest COVID-19 serological study, SARS-CoV-2 antibodies in blood donors have been monitored since 2020. No study has analysed changes in the association between anti-N seropositivity (a marker of recent infection) and geographic and sociodemographic characteristics over the pandemic., Methods: Using Bayesian multi-level models with spatial effects at the census division level, we analysed changes in correlates of SARS-CoV-2 anti-N seropositivity across three periods in which different variants predominated (pre-Delta, Delta and Omicron). We analysed disparities by geographic area, individual traits (age, sex, race) and neighbourhood factors (urbanicity, material deprivation and social deprivation). Data were from 420 319 blood donations across four regions (Ontario, British Columbia [BC], the Prairies and the Atlantic region) from December 2020 to November 2022., Results: Seropositivity was higher for racialized minorities, males and individuals in more materially deprived neighbourhoods in the pre-Delta and Delta waves. These subgroup differences dissipated in the Omicron wave as large swaths of the population became infected. Across all waves, seropositivity was higher in younger individuals and those with lower neighbourhood social deprivation. Rural residents had high seropositivity in the Prairies, but not other regions. Compared to generalized linear models, multi-level models with spatial effects had better fit and lower error when predicting SARS-CoV-2 anti-N seropositivity by geographic region., Conclusions: Correlates of recent COVID-19 infection have evolved over the pandemic. Many disparities lessened during the Omicron wave, but public health intervention may be warranted to address persistently higher burden among young people and those with less social deprivation., (© The Author(s) 2024. Published by Oxford University Press on behalf of the International Epidemiological Association.)

Background and Objectives: No transfusion-associated cases of variant Creutzfeldt-Jakob disease (vCJD) have occurred in more than 20 years. Yet, many countries have maintained blood donor deferral criteria for vCJD. We developed a risk simulation model to reassess the need for vCJD-related deferral criteria in Canada., Materials and Methods: The model provides results separately for Héma-Québec (HQ) and Canadian Blood Services (CBS). The model used a Monte Carlo simulation approach to estimate the risk of having a vCJD-contaminated blood donation ('risk of vCJD') in a simulated cohort of 10 million donors followed for up to 85 years. The model assumed current deferral criteria for vCJD were lifted, which would allow new 'at-risk' donors to give blood. The model accounted for disease prevalence, donors' travel/immigration history, PRNP genotype at codon 129, demographics and the type of labile blood product., Results: In the base case, the risk of vCJD was estimated at zero at both blood services. In the most pessimistic scenario, the risk of vCJD was 6.4 × 10 -9 (i.e., 1 in 157 million donations) at HQ, or ≤1 in 77 million based on the upper bound of the 95% confidence interval (CI). At CBS, this risk was 4.8 × 10 -8 (i.e., 1 in 21 million donations), or ≤1 in 16 million based on the upper bound of the 95% CI., Conclusion: vCJD poses minimal risks to the Canadian blood supply. Current vCJD deferral criteria may, therefore, be lifted with virtually no impact on safety, while significantly expanding the donor base., (© 2023 International Society of Blood Transfusion.)

Background and Objectives: The distribution of rare and specific red cell phenotypes varies between races and ethnicities. Therefore, the most compatible red cell units for patients with haemoglobinopathies and other rare blood requirements are most likely to be found in donors from similar genetic backgrounds. Our blood service introduced a voluntary question asking donors to provide their racial background/ethnicity. Results triggered additional phenotyping and/or genotyping., Materials and Methods: We analysed the results of additional testing performed between January 2021 and June 2022, and rare donors were added to the Rare Blood Donor database. We determined the incidence of various rare phenotypes and blood group alleles based on donor race/ethnicity., Results: Over 95% of donors answered the voluntary question; 715 samples were tested, and 25 donors were added to the Rare Blood Donor database, including five k-, four U-, two Jk(a-b-) and two D- - phenotypes., Conclusion: Asking donors about their race/ethnicity was well received by donors, and the resulting selective testing enabled us to identify individuals with a higher likelihood of being rare blood donors, support patients with rare blood requirements and better understand the incidence of common and rare alleles and red blood cell phenotypes in the Canadian donor population., (© 2023 International Society of Blood Transfusion.)

Hepatitis B surveillance is essential to achieving Canada's goal of eliminating hepatitis B by 2030. Hepatitis B rates, association of infection with vaccine age-eligibility, and risk factors were analyzed among 1,401,603 first-time Canadian blood donors from 2005 to 2020. Donors were classified as having likely chronic or likely resolved/occult infections based on hepatitis B surface antigen, anti-hepatitis B core antigen, and hepatitis B nucleic acid test results. Likely chronically infected and control donors (ratio 1:4) participated in risk-factor interviews. The 2019 rate of likely chronic infection was 61.9 per 100,000 (95% CI 46.5-80.86) and 1449.5 per 100,000 for likely resolved/occult infections (95% CI 1370.7-1531.7). Likely chronic infections were higher in males (OR 3.2; 95% CI 2.7-3.7) and the vaccine-ineligible birth cohort (OR 1.9; 95% CI 1.6-2.2). The main risk factors were living with someone who had hepatitis (OR 12.5; 95% CI 5.2-30.0) and ethnic origin from a high-prevalence country (OR 8.4; 95% CI 5.9-11.9). Undiagnosed chronic hepatitis B may be more prevalent in Canada than currently determined by traditional passive hepatitis B reporting. Blood donor data can be useful in informing hepatitis B rates and evaluating vaccination programs in Canada.

Background and Objectives: Policies regarding medication use vary between blood centres. We evaluated medication use in eligible Canadian Blood Services whole blood donors to inform possible process improvements and allow comparisons between donors and the general population., Materials and Methods: All donors are asked about medication use in the last 3 days, and medications and their reason for use are documented in our donor computer system. Donor computer records were reviewed from January 1, 2020, to March 31, 2022 to extract information on medications by donor age and sex; medications were grouped into therapeutic classes. Stability of medication use over time was determined in a random sample of 100 donors who made at least two donations in the study period., Results: One-third of successful (eligible) donors were taking medications; of these, 80% were on one or two medications. Five classes of medication accounted for 72% of medication use, and 13 classes account for 93% of use. Use remains relatively stable over time., Conclusion: Medication use is common, with a few classes accounting for most use. Drop-down lists and storage of information from one donation to the next may enhance efficiency., (© 2022 International Society of Blood Transfusion.)

Background and Objectives: Donor criteria for diabetes vary significantly. We describe our evolving policies for donors with diabetes, their contribution to the Canadian blood supply and their rate of syncopal reactions compared to other donors., Materials and Methods: All donors are asked if they have diabetes and have taken medications in the last 3 days. We assessed donors with diabetes on various medications, the number deferred over time, and syncopal reactions in donors with diabetes and other donors in our donor reaction database., Results: Policy changes allowing type 2 diabetic donors on oral hypoglycaemics alone, type 2 diabetic donors on oral medications and insulin and type 1 diabetic donors (all on insulin) to donate resulted in a decrease in deferrals from 450 to 22 donors annually. Of donors being treated with medication for diabetes, 11% are receiving insulin as part of their treatment. Syncopal reaction rates were low and not statistically different between diabetic and non-diabetic donors, although confidence intervals (CIs) are large., Conclusion: Policies decreased deferrals while maintaining safety. A longer observation period would strengthen these observations., (© 2022 International Society of Blood Transfusion.)

This study attempted to understand the levels of neutralizing titers and the breadth of antibody protection against wild-type and variant severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Canadian blood donors during the first 3 months of 2021. During this period, it is unlikely that many of the blood donors had received a second dose, since vaccine rollout had not yet ramped up, and less than 2% of the Canadian population had received a second dose of vaccine. A repeated cross-sectional design was used. A random cross-sectional sampling of all available Canadian Blood Services retention samples ( n  = 1,500/month) was drawn monthly for January, February, and March 2021. A tiered testing approach analyzed 4,500 Canadian blood donor specimens for potential evidence of a signal for anti-spike (anti-S), anti-receptor-binding domain (anti-RBD), and anti-nucleocapsid protein (anti-N). Specimens were stratified based on donor-declared vaccination history and then stratified on the presence or absence of anti-N as follows: (i) "vaccinated plus anti-N" ( n  = 5), (ii) "vaccinated and no anti-N" ( n  = 20), (iii) "unvaccinated plus anti-N" ( n  = 20), and (iv) "unvaccinated and no anti-N" ( n  = 20). Randomized specimens were then characterized for neutralizing capacity against wild-type as well as SARS-CoV-2 variants of concern (VOCs) (Alpha [B.1.1.7], Beta [B.1.351], Gamma [P.1], and Delta [B.1.617.2]) using S-pseudotyped virus-like particle (VLP) neutralization assays. There was no neutralizing capacity against wild-type and VOC VLPs within the "no vaccine and no anti-N" group. Neutralization of Beta VLPs was less than wild-type VLPs within "vaccinated plus anti-N," "vaccinated and no anti-N", and "unvaccinated plus anti-N" groups. IMPORTANCE In the first 3 months of 2021 as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination was in the initial stages of a mass rollout, Canadian blood donors had various levels of humoral protection against wild-type and variant of concern (VOC) SARS-CoV-2. Very few Canadians would have received a second dose of a SARS-CoV-2 vaccine. In this study, we identified elevated levels of neutralizing capacity, albeit with reduced neutralization capacity against one or more SARS-CoV-2 strains (wild type and VOCs) in vaccinated blood donors. This broad neutralizing response we present regardless of evidence of natural SARS-CoV-2 infection. Neutralizing capacity against wild type and VOCs varied significantly within the unvaccinated group, with one subset of unvaccinated plasma specimens (unvaccinated and no anti-N) having no measurable wild type- nor variant-neutralizing capacity. The study is important because it indicates that vaccination can be associated with a broad neutralizing antibody capacity of donor plasma against SARS-CoV-2 VOCs.

We have previously used composite reference standards and latent class analysis (LCA) to evaluate the performance of laboratory assays in the presence of tarnished gold standards. Here, we apply these techniques to repeated, cross-sectional study of Canadian blood donors, whose sera underwent parallel testing with four separate SARS-CoV-2 antibody assays. We designed a repeated cross-sectional design with random cross-sectional sampling of all available retention samples ( n  = 1500/month) for a 12 -month period from April 2020 until March 2021. Each sample was evaluated for SARS-CoV-2 IgG antibodies using four assays an Abbott Architect assay targeting the nucleocapsid antigen (Abbott-NP, Abbott, Chicago IL) and three in-house IgG ELISAs recognizing distinct recombinant viral antigens: full-length spike glycoprotein (Spike), spike glycoprotein receptor binding domain (RBD) and nucleocapsid (NP). We used two analytic approaches to estimate SAR-CoV-2 seroprevalence: a composite reference standard and LCA. Using LCA to estimate true seropositivity status based on the results of the four antibody tests, we estimated that seroprevalence increased from 0.8% (95% CI: 0.5-1.4%) in April 2020 to 6.3% (95% CI: 5.1-7.6%) in March 2021. Our study provides further support for the use of LCA in upcoming public health crises, epidemics, and pandemics when a gold standard assay may not be available or identifiable. IMPORTANCE Here, we describe an approach to estimating seroprevalence in a low prevalence setting when multiple assays are available and yet no known gold standard exists. Because serological studies identify cases through both diagnostic testing and surveillance, and otherwise silent, unrecognized infections, serological data can be used to estimate the true infection fatality ratio of a disease. However, seroprevalence studies rely on assays with imperfect sensitivity and specificity. Seroreversion (loss of antibody response) also occurs over time, and with the advent of vaccination, distinction of antibody response resulting from vaccination as opposed to antibody response due to infection has posed an additional challenge. Our approach indicates that seroprevalence on Canadian blood donors by the end of March 2021was less than 10%. Our study supports the use of latent class analysis in upcoming public health crises, epidemics, and pandemics when a gold standard assay may not be available or identifiable.

Background: This pilot study assesses the ability of plasma collected from Canadian blood donors in the first wave of the SARS-CoV-2 pandemic to neutralize later SARS-CoV-2 variants of concern (VOCs)., Study Design and Methods: A repeated cross-sectional design was used, and a random cross-sectional sample of all available Canadian Blood Services retention samples (n = 1500/month) was drawn monthly for April and May of 2020. Qualitative IgG analysis was performed on aliquots of specimens using anti-spike, anti-receptor binding domain, and anti-nucleocapsid protein enzyme-linked immunosorbent assays as well as the Abbott Architect SARS CoV-2 IgG assay (Abbott Laboratories) against the anti-nucleocapsid protein. Selected plasma specimens were then assessed for neutralization against VOCs using pseudotyped lentivirus inhibition assays as well as plaque reduction neutralization test 50% (PRNT 50 )., Results: Six specimens with a high neutralizing titer against wild-type SARS-CoV-2 and three specimens with a low neutralizing titer against wild-type SARS-CoV-2 were chosen for further analysis against VOCs. Four of six high neutralizing titer specimens had a reduced neutralizing capacity against beta VOCs by both neutralization methods. Three of six high neutralizing titer specimens had reduced neutralization capacity against gamma VOCs., Conclusions: This preliminary data can be used as a justification for limiting the use of first wave plasma products in upcoming clinical trials but cannot be used to speculate on general trends in the immunity of Canadian blood donors to SARS-CoV-2., (© 2021 The Authors. Transfusion published by Wiley Periodicals LLC on behalf of AABB.)

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., (© 2021 International Society of Blood Transfusion.)

Background: There are several strategies to reduce donor reactions. We report donor participation and reaction rates before and after implementing multiple measures at Canadian Blood Services., Study Design and Methods: We introduced a structured program of 500 mL of water and a salty snack pre-donation and applied muscle tension (AMT) during donation. Donors were not deferred for out of range blood pressure (BP); however, BP was measured in first time donors. Time on the donation chair post-donation was decreased from 5 to 2 min for repeat donors. We assessed participation rates using our quarterly survey of 10,000 recent donors. We extracted vasovagal reactions with loss of consciousness (LOC) from our operational database and compared pre-implementation (Oct 12,018-March 31,2019) and post-implementation (Oct 12,019-March 31,2020) periods., Results: Survey response rates varied from 11% to 16%. The percentage of donors who drank the water and ate the salty snack increased from 58% to 82% and 44% to 70% over 4 quarters; those performing AMT increased from 24% to 41%. Reactions decreased from 19.07 per 10,000 (744 reactions in 390,123 donations) to 14.04 per 10,000 (537 in 382,382 donations) (p < .0001). No first-time donors with high BP (n = 684) but 5 with low BP (n = 718) had reactions, CI were very large., Conclusions: Achieving optimal participation was challenging. After implementation of a donor wellness initiative based on best practice, rates of vasovagal reactions with LOC decreased by 25%. A larger dataset is necessary to assess the safety contribution of BP deferrals when other mitigation measures are in place., (© 2021 AABB.)

Background: The use of pre-/post-exposure prophylaxis (PrEP/PEP) may interfere with routine HIV screening. As a result, blood services worldwide have adopted a variety of deferral policies to mitigate increased residual risk. In this study, we evaluated the operational impact of modifying the donor health questionnaire (DHQ) to include explicit questions to assess PrEP/PEP exposure., Study Design and Methods: We conducted a retrospective study between June 2019 and October 2020 of all blood donors attempting to donate at Canadian Blood Services. Sixteen-months post-implementation, we summarized self-reported PrEP/PEP rates and their indications for use. We also assessed deferral rates and the sensitivity of using existing risk questions to defer people exposed to PrEP/PEP., Results: Of 1,122,075 donations, 89 people (eight per 100,000 donations) reported PrEP (64%)/PEP (34%) use in the last 4 months. People exposed to PrEP were more likely to be men (94%) and taking PrEP for lifestyle reasons (87%). In contrast, indications for PEP use included occupational exposure (50%) and sexual assault (27%). Most donors who answered affirmatively to PrEP/PEP exposure were deferred (96%). If potential donors were not directly asked about their PrEP/PEP use, the majority would not have been deferred for any other reasons (PrEP 32/57 (56%) and PEP 15/30 (50%))., Conclusion: Not all blood services have adopted direct questions to identify PrEP/PEP exposure; some rely on existing DHQ questions. In Canada, despite DHQ questions such as medication use in the last 3-days, more than half of people exposed to PrEP/PEP would not have been identified and deferred., (© 2021 AABB.)

Background: Case detection underestimates the burden of the COVID-19 pandemic. Following the first COVID-19 wave, we estimated the seroprevalence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) among blood donors across Canada., Study Design and Methods: This serial cross-sectional study was conducted between May 9 and July 21, 2020 from blood donors donating at all Canadian Blood Services locations. We used the Abbott Architect assay to detect SARS-CoV-2 IgG antibodies from retention plasma. Seroprevalence was standardized to population-level demographics and assay characteristics were adjusted using the Rogan-Gladen equation. Results were stratified by region, age, ethnicity, ABO groups, and quantiles of material and social deprivation indices. Temporal trends were evaluated at 2-week intervals. Univariate and multivariate logistic regression compared SARS-CoV-2 reactive to non-reactive donors by sociodemographic variables., Results: Overall 552/74642 donors, had detectable antibodies, adjusted seroprevalence was 7.0/1000 donors (95% CI; 6.3, 7.6). Prevalence was differential by geography, Ontario had the highest rate, 8.8/1000 donors (7.8, 9.8), compared to the Atlantic region 4.5/1000 donors (2.6, 6.4); adjusted odds ratio (aOR) 2.2 (1.5, 3.3). Donors that self-identified as an ethnic minority were more likely than white donors to be sero-reactive aOR 1.5 (1.2, 1.9). No temporal trends were observed., Discussion: Worldwide, blood services have leveraged their operational capacity to inform public health. While >99% of Canadians did not show humoral evidence of past infection, we found regional variability and disparities by ethnicity. Seroprevalence studies will continue to play a pivotal role in evaluating public health policies by identifying trends and monitor disparities., (© 2021 AABB.)

Background: Alternative screening questions could permit low-risk men who have sex with men (MSM) to donate blood without a time deferral. We performed a study to determine the proportion of current donors who may be deferred by various questions and their comfort with them., Study Design and Methods: Donors attending collection sites in Canada in January and February 2018 were offered one of two questionnaires but not both. Questionnaire 1 asked about risk behaviors; Questionnaire 2 rated comfort with the questions. Volunteers uncomfortable with questions participated in short qualitative telephone interviews to understand reasons. Quantitative data were analyzed using χ 2 statistics., Results: Of 36 241 donors attending, 31 904 (88%, Period 1) completed Questionnaire 1; of 34 947, a total of 30 278 (87%, Period 2) completed Questionnaire 2; 294 completed an interview. In the past 3 months 3.1% (95% confidence interval [CI], 3.1%-3.6%) had more than one partner; 6.0% (95% CI, 5.7%-6.2%) had a new partner; 6.7% (95% CI, 6.4%-6.9%) were in a nonexclusive relationship; 11.2% (95% CI, 10.9%-11.6%) had at least one of these; 3.7% (95% CI, 3.4%-3.9%) had anal sex; and 62.8% (95% CI, 62.2%-63.3%) had condomless sex. More than 6% were uncomfortable with each question, but more (17.2%; 95% CI, 16.8%-17.7%) were uncomfortable with anal sex. Key reasons for discomfort were questions being too personal and unclear safety benefit., Conclusion: Most donors are comfortable answering alternative questions (except very personal ones) but question the benefit. Implementing alternative questions would result in substantive deferrals. Other policies such as using an MSM capture question to ask additional questions only to MSM should be considered., (© 2020 AABB.)

Iron deficiency is a global problem in women of child-bearing age and is associated with adverse maternal and newborn outcomes. Repeated blood donations deplete iron stores and decrease hemoglobin levels. However, the clinical impact of iatrogenic iron deficiency on mothers and neonates due to blood donation is uncertain. The objective of this study was to assess the association between repeated blood donations in female donors of child-bearing age and the associated risk of adverse maternal and neonatal outcomes. We undertook an observational cohort study of all women who delivered a live or stillborn infant in Ontario, Canada, between 1 January 2010 and 31 March 2012 using birth record data from the Better Outcomes Registry & Network, Canadian Blood Services, and the Institute of Clinical Evaluative Sciences. Only a woman's first pregnancy within the study time frame was included for analysis. We excluded women <18 years or >50 years of age at the time of delivery and multiple birth pregnancies. Data on all female donors who made whole blood donations between 1 January 2007 and 31 March 2012 were obtained from Canadian Blood Services. The primary newborn outcome was diagnosis of a small-for-gestational-age neonate (less than 10th centile). Secondary outcomes were preterm birth, stillbirth, APGAR <4 at 5 minutes, cord pH <7, neonatal death, maternal transfusion, infection, preeclampsia, gestational hypertension, gestational diabetes, placental abruption, and maternal death. Regression models evaluated the effect of repeated donation and the time interval between donations and conception on neonatal and maternal outcomes while adjusting for important clinical and demographic risk factors. A total of 260 037 women delivered live or stillborn singleton infants between 1 January 2010 and 31 March 2012. A total of 7919 (3.0%) women were blood donors, with a mean of 2.43 ± 2.10 lifetime donations. Mean maternal age at the time of delivery for nondonors and donors was 30.30 ± 5.38 and 29.74 ± 4.94 years, respectively. Small for gestational age occurred in 23 706 (9.4%) of neonates born to nondonors and 526 (6.6%) of neonates born to donors. There was a reduction in the risk of small for gestational age with increasing number of lifetime donations (adjusted odds ratio 0.89 [0.86-0.92] per additional donation). For the prespecified secondary outcomes, we observed a reduction in the risk of low birth weight (adjusted odds ratio 0.95 [0.91-0.98] per additional donation). There was no association with other secondary neonatal or maternal outcomes except for maternal hypertension. Proximity of donation to conception had no effect on risk of a small-for-gestational age neonate. Our data suggest that there is no increased risk of deleterious neonatal and maternal outcomes associated with repeated blood donations prior to pregnancy. Although possibly a result of a healthy donor effect, our findings are reassuring to female donors and their children as well as to clinicians and blood system stakeholders seeking to inform policy decisions., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Background and Objectives: In Canada, the deferral for men who have sex with men (MSM) was decreased from a permanent deferral to a 5-year then a 12-month deferral. Current HIV testing can detect an HIV infection in donated blood within 2 weeks of exposure; thus, a 12-month deferral may be unnecessarily restrictive. We aimed to estimate the residual risk of HIV if the deferral were further decreased to 3 months., Materials and Methods: Using a deterministic model with stochastic Monte Carlo simulation, residual risk of HIV was the sum of testing error, assay sensitivity and window-period risks. Data inputs were estimated from donor surveillance, donor surveys and published data. Residual risk was modelled at baseline and using three scenarios: (1) most likely - non-compliance, HIV prevalence and incidence rates of MSM are unchanged; (2) optimistic - non-compliance improves by 50%; and (3) pessimistic - non-compliance, HIV prevalence and incidence rates of MSM all double., Results: HIV residual risk at baseline was 1 in 36·0 million donations (95% CI 1 in 1 504 907 million, 10·5 million); in the most likely scenario 1 in 34·2 million (1 in 225 534 million, 8·7 million); in the optimistic scenario 1 in 36·0 million (1 in 282 618 million, 9·5 million); in the pessimistic scenario 1 in 16·7 million (1 in 39 469 million, 6·0 million). All confidence intervals overlapped., Conclusion: With very low modelled risk under a 12-month deferral, the additional risk with a 3-month deferral is very low. This is true even with a pessimistic scenario., (© 2019 International Society of Blood Transfusion.)

Background: The erythrocytic protozoan parasite Babesia microti, the cause of human babesiosis, is transmitted not only by tick bites but also via blood transfusion. B. microti is endemic in the northeastern/upper midwestern United States, where partial screening of blood donations has been implemented. In Canada, a 2013 study of approximately 14,000 donors found no B. microti antibody-positive samples, suggesting low risk at that time., Methods: Between June and October 2018, 50,752 Canadian donations collected from sites near the US border were tested for Babesia nucleic acid by transcription-mediated amplification (TMA). Reactive donations were tested for B. microti by IgG immunofluorescence assay and polymerase chain reaction. A subset of 14,758 TMA nonreactive samples was also screened for B. microti antibody. Donors who tested reactive/positive were deferred, asked about risk factors, and were requested to provide a follow-up sample for supplemental testing., Results: One sample from Winnipeg, Manitoba, was TMA and antibody reactive. Of the 14,758 TMA-nonreactive donations tested for antibody, four reactive donations were identified from southwestern Ontario near Lake Erie. None of the interviewed donors remembered any symptoms, likely tick exposure, or relevant travel within Canada or the United States., Conclusions: This is the largest B. microti prevalence study performed in Canada. The results indicate very low prevalence, with only one TMA-confirmed-positive donation of 50,752 tested. This donor was from the only region in Canada where autochthonous infection has been reported. Seropositive donations in southwestern Ontario suggest low prevalence; travel should not be ruled out given the proximity to the US border., (© 2019 AABB.)

Background and Objectives: Eight published studies modelled the impact of changing from a lifetime to time-limited deferral for men who have sex with men (MSM); each predicted greater risk impact than has been observed. This study uses these previous efforts to develop an 'optimized' model to inform future changes to MSM deferrals., Materials and Methods: HIV residual risk was calculated using observed HIV incidence/prevalence prior to the change in MSM deferral, then with the additional MSM expected under a 12-month deferral for five compliance scenarios, and finally using data observed after implementation of the deferral. Monte Carlo simulation calculated 95% confidence intervals (CI)., Results: The architecture of reviewed models was sound, and two were selected for combination into the optimized model. HIV risk estimated by this in the UK under MSM lifetime deferral was 0·102 (95% CI: 0·050-0·172) per million. The model predicted from a 27·8% decrease to a 47·6% increase depending upon compliance pre-implementation of the 12-month deferral. A decrease of 0·9% was observed post-implementation. For Canada, HIV risk under a 5-year deferral was 0·050 (95% CI: 0·00003-0·122) per million. Pre-implementation of the 12-month deferral, the model predicted from 30·2% decrease to 10-fold increase. A decrease of 47·0% was observed after implementation., Conclusion: The optimized model predicted HIV risk under 12-month MSM deferral in UK and Canada would remain low, and this was confirmed post-implementation. While the model is adaptable to other deferral scenarios, improved data quality would improve precision, particularly estimates of incidence in individuals likely to donate., (© 2019 International Society of Blood Transfusion.)

Background: To reduce donor iron deficiency in whole blood donors, we changed our hemoglobin (Hb) cutoff in males and interdonation interval in females., Study Design and Methods: A change in messaging to females in fall 2016 was followed by changing the interdonation interval from 56 to 84 days in the appointment booking system (December 2016) and actual donation criterion (March 2017). The minimum Hb for males increased from 125 g/L to 130 g/L (March 2017). We evaluated Hb levels and deferral rates, donor presentations with a Hb level below 120 g/L, donation frequency, and donor base size before and after these changes., Results: The Hb deferral rate decreased in females from 13.0% to 9.5%, increased in males from 1.2% to 2.1%, and decreased overall from 6.8% to 5.4% (all p < 0.001). Mean Hb increased from 135.0 g/L to 136.2 g/L in females and from 149.9 g/L to 150.6 g/L in males (both p < 0.0001). The percentage of presentations with Hb below 120 g/L decreased by 27% in males and females (p < 0.001). Annual donation frequency decreased by 12% in females and 4% in males; the donor base was expanded by 5.8%., Conclusions: Many positive impacts were seen for female donors, including a shift in the Hb distribution curve to the right, and a large reduction in Hb deferrals. For males, there was an increase in Hb deferrals and a small increase in mean Hb. Changes were related to both reduced donation frequency and a shift in composition of the donor base., (© 2019 AABB.)

Background: Some countries impose an upper age limit on whole blood and double RBC donation while others do not. We evaluated the safety of blood donation in older individuals (≥71 years), and their contribution to the blood supply of five countries., Study Design and Methods: Twelve blood center members of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative from four countries with no upper age limit for whole blood and double RBC donation (Canada, New Zealand, England, and the United States) or an upper age limit of 80 (Australia) provided 2016 data on donors and donations, deferral rates, and vasovagal reactions by donor age and sex. Donors under age 24 were included in the number of total donors and donations, but not in deferral and reaction rate comparisons., Results: Older donors accounted for 1.0% (New Zealand) to 4.3% (United States) of donors, and 1.5% (New Zealand) to 5.6% (United States) of donations; most were between ages 71 and 76. The deferral rate was higher in older compared to 24- to 70-year-old males, but very similar between older and younger females. In contrast, vasovagal reaction rates were either lower (male donors) or similar (female donor for reactions with loss of consciousness) in older compared to 24- to 70-year-old donors., Conclusions: Exclusion solely based on older age appears to be unwarranted based on safety concerns such as donor reactions. Healthy older individuals can continue to safely donate and make a significant contribution to the blood supply past arbitrary age limits., (© 2019 AABB.)

Background: In non-endemic countries, malaria risk is addressed by selectively testing or deferring at-risk donors. These policy decisions were made using a variety of decision-making frameworks prior to the development of the Alliance of Blood Operators Risk Based Decision-Making Framework. It is unclear whether the range of items assessed in the decision-making process would be increased if the Framework were used. We compared assessments considered in France, England and Australia for decisions to implement selective testing, plus donor selection criteria (Canada and the USA included) with those recommended by the Framework., Materials and Methods: Elements of the Framework were identified: the intervention, safety threat, availability threat, donor impact, financial implications, risk communication, stakeholder and regulatory aspects. Decisions about selective testing and donor selection criteria were analysed separately. Assessments were compared against elements of the Framework and the level of concern for considerations rated., Results: Sufficiency of the blood supply (plus safety in France) were the drivers for selective testing; main trade-offs were high operational impact and cost. In three donor criteria examples, transfusion-transmitted malaria cases prompted the change. Social concerns were high in France and Australia, political/regulatory concerns influenced decisions in France, Australia and Canada, while sufficiency was a consideration in Canada and the USA. Decision trade-offs involved moderate operational impact., Discussion: The assessments considered in each country were generally consistent with the assessments recommended by the Framework. When data supported quantified risk assessment, safety and operational feasibility had the greatest weight. When risk was not well defined, contextual factors such as social and political concern had greater weight.

Background: We assessed donor return rates, donation frequency, and factors related to the evolution of ferritin levels 2 years after entering donors into a large operational study of ferritin testing., Study Design and Methods: Ferritin testing was done on donors from representative clinics (n = 12,595). Low-ferritin donors (<25 μg/L) were informed and not called for 6 months to book a donation. Approximately 37% of donors had ferritin retested on a return donation. Return rate and donation frequency were monitored, and a logistic regression model was constructed., Results: The return rate was lower in low-ferritin donors (67% vs. 78%), particularly in women who were first-time donors (36% vs. 61%). Returning low-ferritin donors made fewer donations in the 2 years after notification compared to the 2 years prenotification (4.5 vs. 7.5 for men, 3.0 vs. 5.0 for women), while donation frequency was lower and increased slightly for normal-ferritin donors (4.7 vs. 4.4 for men, 3.6 vs. 3.1 for women). An increased number of donations, shorter interdonation intervals, female sex, and younger age are associated with low ferritin levels on initial and repeat testing. Some recovery of ferritin occurred, but most low-ferritin donors continued to have low or borderline levels on retesting., Conclusion: Informing donors of low ferritin results had a long-lasting impact on return rates and donation frequency, requiring recruitment efforts to maintain adequacy of supply. Increasing the interdonation interval leads to some improvement in ferritin levels; more sustained efforts to encourage donors to improve iron intake are needed to achieve long-term benefit., (© 2018 AABB.)

Background: We compared donor and general population demographics over time to provide insight into current donation patterns and the future adequacy of the blood supply., Study Design and Methods: Seventeen blood center members of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative from 12 countries provided the number of donors and people in the general population by demographic category for 2001 and 2011, changes in age criteria, and percentage of first-time donors. We calculated the median age of donors and the general population and determined the percentage of each group in age and sex cohorts., Results: Age criteria vary, with upper limits recently liberalized in several countries. In 2011, the percentage of first-time donors ranged from 10% to 41%. The median age of the donor and general population increased from 2001 to 2011 in most countries, as did the percentage of the general population over 60. The youngest donor cohort is overrepresented to a variable degree; this tendency increased over time. Although still underrepresented, older donors contributed more in 2011. A large middle-aged cohort is aging at a rate exceeding the progression of time, while 25- to 45-year-olds are relatively underrepresented., Conclusions: All participating countries are experiencing aging of their general population. Donor demographics differ substantially between countries; this can be only partly explained by population demographics and age criteria. Many countries have an aging middle-aged donor and population cohort and are increasingly relying on their youngest donors to contribute disproportionately to the blood supply., (© 2017 AABB.)

Background: The recent spread of the Zika virus to the Americas and the recognition that it can cause severe disease in the developing fetus has prompted the adoption of measures to mitigate the risk that this virus might pose to transfusion safety. In nonendemic countries, the risk to transfusion results from donors traveling to an endemic region. Canada implemented a 21-day temporary deferral for prospective donors who traveled to such regions. We present the rationale for this policy, including a quantitative risk assessment supported by a Monte Carlo simulation., Study Design and Methods: The model considered the following parameters, each with specified values and ranges: the probability that a donor recently returned from a Zika-endemic region, the duration of travel to this region, the daily risk of acquiring Zika while in an endemic region, and the incubation and viremic periods. We ran the simulation 20 times, each with 10 million iterations., Results: In the absence of any travel deferral, 32 donors (range, 20-46 donors) would be able to donate while still being at risk of transmitting Zika, corresponding to a rate of 1:312,500 (range, 1:217,000 to 1:500,000). None of these donors would be viremic beyond 21 days after returning from their travel, with a risk estimated at less than 1:200,000,000., Conclusions: A 21-day temporary travel deferral offers an extremely wide margin of safety for the possible transmission of Zika by a donation obtained from someone who recently returned from a country where the virus is circulating., (© 2017 AABB.)

Background: Hepatitis E virus (HEV) is a virus of emerging importance to transfusion medicine as studies on blood donors and other populations demonstrate that the prevalence of endemic cases is higher than previously recognized and the risk to vulnerable transfusion recipients is not insignificant., Study Design and Methods: We carried out an HEV prevalence study on 13,993 Canadian blood donors with polymerase chain reaction (PCR) testing on all donors and antibody testing on a subset of 4102 donors. HEV antibody-positive and age- and sex-matched antibody-negative donors were invited to participate in a scripted telephone interview about risk factors., Results: There were no PCR-positive samples found (95% confidence interval [CI], 0%-0.026%). The seroprevalence of HEV in our tested population was 5.9% (95% CI, 5.16%-6.59%). HEV antibody positivity was associated with male sex and increasing age. In case-control analysis history of living outside Canada (odds ratio [OR], 2.9; 95% CI, 1.56-5.32) and contact with farm animals (OR, 1.5; 95% CI, 1.01-2.28) were associated with HEV seropositivity., Conclusion: This is the largest data set to date on HEV infection in Canada. Results suggest low lifetime exposure to HEV and that infectious donations are rare., (© 2017 AABB.)

Background: We assessed risk groups for iron deficiency and the feasibility and efficacy of ferritin testing in a large blood center., Study Design and Methods: Donors were informed of possible testing in the predonation pamphlet. Plasma ferritin was measured on retention samples (n = 12,595) from representative clinics. Low-ferritin donors (<25 µg/L) were sent a letter and information sheet and not called for 6 months. Ferritin testing was repeated on 25% of donors; donor return rate and frequency were monitored., Results: Low-ferritin donors represented 2.9% of first-time and reactivated (no donation in past 12 months) male donors, 32.2% of first-time and reactivated female donors, 41.6% of repeat male donors, and 65.1% of repeat female donors. A mean of 11.7 months after index donation, the return rate was 76% for normal and 58% for low-ferritin donors; returning low-ferritin donors had made approximately one fewer donation. Ferritin increased by 16.3 and 12.1 µg/L in male and female low-ferritin donors and decreased by 17 µg/L in male and female normal-ferritin donors., Conclusion: The minimum hemoglobin level will be increased to 130 g/L for male donors and the minimum interdonation interval changed to 84 days (four donations yearly) for female donors based on iron deficiency risk groups. Large-scale ferritin testing was feasible. Donors informed of low-ferritin results had a lower return rate, donated less often, and had an increase in ferritin on return, approximately 1 year after initial testing, compared to donors with normal ferritin results., (© 2016 AABB.)

Purpose of Review: The review summarizes recent publications on the contentious issue of donor deferral criterion for men who have sex with men (MSM)., Recent Findings: Recent studies from the United States and China demonstrated that MSM is still a frequent risk factor for HIV-positive donors. Noncompliance is an important factor in the overall risk of HIV transmission but does not appear to be affected by the length of the deferral period. A major US study found a 2.6% noncompliance rate with the current indefinite deferral for MSM; similar or lower rates were found in other jurisdictions with shorter deferral periods. Several countries have had a defined deferral period of 1 year or 5 years in place long enough to determine that increases in HIV-positive cases predicted by modeling studies did not actually occur, suggesting that the assumptions made in these models are overly conservative., Summary: In summary, MSM eligibility policies are slowly changing around the world, with the US FDA now permitting a 1-year deferral. Transparency, involvement of stakeholders, and careful evaluation of risk and societal benefit should be part of future policy discussions on this issue.

Background: Informing donors of their ferritin status is one possible mitigating strategy to reduce iron deficiency in donors., Study Design and Methods: We evaluated the impact of informing donors of their ferritin status on their donation frequency, understanding of iron needs, and actions to improve iron intake 2 years after their inclusion in a prospective observational cohort study., Results: Informing donors of low ferritin results decreased return rate in first-time and repeat donors, and the median number of donations declined from three to two donations/year in returning donors with low ferritin on index donation compared to an increase from 1.5 to 2.5 donations/year in donors with normal ferritin. An electronic questionnaire demonstrated that approximately 60% of low ferritin donors saw their primary medical practitioner, and half of this group started iron. Qualitative interviews revealed suboptimal understanding of iron needs and poor compliance with iron supplementation., Conclusion: Providing donors with results of ferritin testing may reduce return rates and donation frequency in the 2 years after testing. Simply providing donors with ferritin results and an information sheet is often inadequate to improve donors' understanding of iron needs and may not lead to a substantive increase in iron intake over time., (© 2016 AABB.)

Background: The deferral for men who have sex with men (MSM) changed from a permanent deferral since 1977 to a 5-year deferral on July 22, 2013, in Canada. We assessed the impact on safety and adequacy of the blood supply at Canadian Blood Services., Study Design and Methods: Human immunodeficiency virus (HIV) rates were monitored from January 1, 2010, to July 21, 2015. Risk factors were assessed in notification interviews. Anonymous online surveys of male whole blood donors assessed compliance before and after implementation., Results: HIV rates were 0.2, 0.5, and 0.51 per 100,000 donations in 2010 to 2012; they were 0.54 and 0.22 in the first and second years after implementation (p = 0.8). Of four male HIV-positive donors after implementation, three denied risk factors and one knew he had HIV. Before implementation 9669 of 19,437 (49.7%) donors participated in the survey, and after implementation, 6881 of 18,934 (36.3%). Before implementation 0.67% of male donors were noncompliant, and after implementation, 0.44%. There was no difference before versus after implementation in male donors with MSM history in the past 5 years (0.37% vs. 0.43%, p = 0.54). After implementation, eligible MSM donors increased (0.42% vs. 0.66%, p = 0.04), with approximately 500 more donors in 2014., Conclusion: Implementation of a 5-year deferral for MSM had no impact on HIV rates in 2 years of postimplementation monitoring. Donor compliance improved after implementation due to MSM donors who were previously ineligible becoming eligible. There was no change in the percentage of male donors with recent male partners but there was a modest increase in eligible MSM in the donor pool., (© 2015 AABB.)

Background: Human babesiosis, caused by the intraerythrocytic protozoan parasite Babesia microti, is primarily transmitted by tick bites and is also transmitted by transfusion. Infections have been identified in U.S. blood donors close to Canadian borders. We aimed to assess the risk of transfusion-transmitted babesiosis in Canada by examining infections in ticks and seroprevalence in blood donors., Study Design and Methods: Passive surveillance (receipt of ticks submitted by the public) was used to identify regions for tick drag sampling (active surveillance, 2009-2014). All ticks were tested for B. microti using an indirect immunofluorescent antibody assay (Imugen, Inc.). Between July and December 2013, blood donations from selected sites (southern Manitoba, Ontario, Québec, New Brunswick, and Nova Scotia) near endemic U.S. regions were tested for antibody to B. microti. Donors completed a questionnaire about risk travel and possible tick exposure., Results: Of approximately 12,000 ticks submitted, 14 were B. microti positive (10 in Manitoba, one in Ontario, one in Québec, two in New Brunswick). From active tick surveillance, six of 361 ticks in Manitoba were positive (1.7%), three of 641 (0.5%) in Québec, and none elsewhere. There were 26,260 donors at the selected sites of whom 13,993 (53%) were tested. None were positive for antibody to B. microti. In 2013, 47% of donors visited forested areas in Canada, and 41% traveled to the United States., Conclusion: The data do not suggest that laboratory-based testing is warranted at this time. However, there are indicators that B. microti may be advancing into Canada and ongoing monitoring of tick populations and donor seroprevalence is indicated., (© 2015 AABB.)

Background: Travel to malaria risk areas such as Mexico is a common source of donor deferral in Canada. On February 21st, 2011 the deferrable regions in Mexico were revised to permit donation if donors travelled to the state of Quintana Roo, Mexico, a popular ocean-side resort area., Materials and Methods: Canadian travel data and malaria deferral rates since 2007 were plotted to examine trends. Deferral records in one centre were accessed from January to April, 2011 to tabulate travel destinations of deferred donors immediately before and after the change., Results: Travel to Mexico and the Caribbean accounts for 63% of general population travel, and travel to Mexico has been increasing (P <0.05). Deferral for short-term malaria risk travel has a strong seasonal trend with peaks in the winter and troughs in the summer. Approximately 36,000 fewer donations were lost following the change, a reduction of 37% from the previous year. Deferrals in one centre increased for Caribbean/Central America after the change (P <0.05) consistent with the seasonal trend, but decreased for Mexico (P <0.05)., Discussion: Deferrals for malaria risk travel are substantial. Careful revision and refinement of risk areas of travel can significantly reduce the burden of deferral.

Background: Adverse donor reactions can result in injury and decrease the likelihood of donor return. Reaction reports captured in the blood center's database provide an incomplete picture of reaction rates and risk factors., Study Design and Methods: We performed an anonymous survey, mailed to 40,000 donors in 2008, including questions about symptoms, height, weight, sex, and donation status. Reaction rates were compared to those recorded in our database. Possible risk factors were assessed for various reactions., Results: The response rate was 45.5%. A total of 32% of first-time and 14% of repeat donors reported having any adverse symptom, most frequently bruising (84.9 per 1000 donors) or feeling faint or weak (66.2 per 1000). Faint reactions were two to eight times higher than reported in our database, although direct comparison was difficult. Younger age, female sex, and first-time donation status were risk factors for systemic and arm symptoms. In females, low estimated blood volume (EBV) was a risk factor for systemic symptoms. Only 51% of donors who consulted an outside physician also called Canadian Blood Services. A total of 10% of first-time donors with reactions found adverse effects information inadequate., Conclusion: This study allowed us to collect more information about adverse reactions, including minor symptoms and delayed reactions. Based on our findings of the risk factors and frequency of adverse reactions, we are implementing more stringent EBV criteria for younger donors and providing more detailed information to donors about possible adverse effects and their management., (© 2012 American Association of Blood Banks.)

Background: Various testing strategies may reduce the risk of Chagas disease transmission in nonendemic, low-prevalence countries. Results of the first year of selective testing of at-risk donors at Canadian Blood Services are reported., Study Design and Methods: Since February 2009, platelets were not produced from at-risk donors. Since May 2010, at-risk donors were tested for Trypanosoma cruzi antibodies. Donors testing positive were interviewed about risk factors, and lookback studies were initiated., Results: There were 7255 at-risk donors of 421,979 donors screened (1.72%). Risk factors were born in Latin America (50.6%), mother or maternal grandmother born in Latin America (28%), and 6 months or more travel history or residence in Latin America (19%). Sixteen (16) at-risk donors had T. cruzi repeat-reactive test results of whom 13 confirmed positive. Eleven of 13 were born in Latin America (nine in Paraguay and two in Argentina), and the other two were born in Canada but had short-term travel history and mothers who had been born in Latin America. Ten of the donors spoke German as their first language (all of those born in Paraguay and one born in Canada). There were 148 previous donations (176 components transfused) evaluated by lookback, of which 28% of recipients could be tested. None were positive., Conclusion: Selective testing has mitigated a small risk to the blood supply with very few false-positive results. Most positive donors were born in a risk country, with a concentration of German-speaking immigrants from Paraguay. Residency or travel alone were not clear risk factors., (© 2012 American Association of Blood Banks.)

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., (© 2011 American Association of Blood Banks.)