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BACKGROUND In Canada, the deferral for men who have sex with men (MSM) has been progressively reduced from a permanent deferral for MSM since 1977, to 5 years, 1 year, and, most recently, 3 months. We estimated human immunodeficiency virus (HIV) residual risk and compliance with the MSM time deferral after each change. METHODS Four anonymous online compliance surveys were carried out before and after each change. HIV incidence and prevalence were monitored from 2010 to 2021. Residual risk was estimated using the incidence-window period model. RESULTS Human immunodeficiency virus prevalence, incidence, and residual risk did not change with incrementally shorter MSM deferrals. The residual risk per million donations post 3-month deferral was 0.05 (0.001-0.371). Men with temporally remote MSM history became eligible and, therefore, compliant as the deferral periods decreased (Cochran-Armitage p value =

In late 2019 the respiratory illness, Corona Virus Disease-19 caused by the SARS-CoV-2 virus emerged in China and quickly spread to other countries. The primary mode of transmission is person-to-person via respiratory droplets. SARS-CoV-2 has been identified in conjunctiva. Transmission by cornea transplant has not been reported but is theoretically possible. We aimed to estimate the possible risk of transmission in Canada via cornea transplant during the first wave of the pandemic, and the potential risk reduction from testing decedents. We constructed a deterministic model in which the risk of transmission was estimated as the product of three proportions: decedents with SARS-CoV-2 infection, corneas that are NAT positive, and NAT positive corneas presumed to transmit. Risk was estimated according to 3 scenarios: most likely, optimistic and pessimistic. At the peak of the first wave of the pandemic risk was estimated to be 1 in 63,031 cornea transplants in Canada but could be as low as 1 in 175,821 or as high as 1 in 10,129. It would take 16 years at the peak infection of the first wave of the pandemic to observe 1 transmission. Testing would reduce the risk of 1 in 63,031 to 1 in 210,104 assuming 70% test sensitivity. The theoretical risk of SARS-CoV-2 transmission by cornea transplant is extremely low and decedent testing is unlikely to be beneficial.

BACKGROUND Babesia microti has gained a foothold in Canada as tick vectors become established in broader geographic areas. B. microti infection is associated with mild or no symptoms in healthy individuals but is transfusion-transmissible and can be fatal in immunocompromised individuals. This is the first estimate of clinically significant transfusion-transmitted babesiosis (TTB) risk in Canada. STUDY DESIGN AND METHODS The proportion of B. microti-antibody (AB)/nucleic acid amplification test (NAT)-positive whole blood donations was estimated at 5.5% of the proportion of the general population with reported Lyme Disease (also tick-borne) based on US data. Monte Carlo simulation estimated the number and proportion of infectious red cell units for three scenarios: base, localized incidence (risk in Manitoba only), and donor study informed (prevalence from donor data). The model simulated 1,029,800 donations repeated 100,000 times for each. RESULTS In the base scenario 0.5 (0.01, 1.75), B. microti-NAT-positive donations would be expected per year, with 0.08 (0, 0.38) recipients suffering clinically significant TTB (1 every 12.5 years). In the localized incidence scenario, there were 0.21(0, 0.7) B. microti-NAT-positive donations, with 0.04 (0, 0.14) recipient infections (about 1 every 25 years). In the donor study informed scenario, there were 4.6 (0.3, 15.8) B. microti-NAT-positive donations expected, and 0.81 (0.05, 3.14) clinically significant TTB cases per year. DISCUSSION The likelihood of clinically relevant TTB is low. Testing would have very little utility in Canada at this time. Ongoing pathogen surveillance in tick vectors is important as B. microti prevalence appears to be slowly increasing in Canada.

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.

Background At Canadian Blood Services, platelet concentrate (PC) shelf life was extended to 7 days with a large-volume, delayed-sampling bacterial screening algorithm. We present the development study and postimplementation results. Study design and methods In the development study, PCs inoculated with five bacteria (various concentrations) were incubated for 7 days with daily sampling for BacT/ALERT cultures and bacterial quantification. After implementation, from August 2017 to December 2019, a total of 223 156 pools and 39 725 apheresis units and 5310 outdated PCs were screened. Since March 2018, cocomponents associated to false-positive results have been released to inventory. Results In the development study, Klebsiella pneumoniae, Serratia marcescens, and Staphylococcus aureus were detected at concentrations of at least 0.01 colony-forming units (CFUs)/mL at 24 hours postinoculation. However, Staphylococcus epidermidis was detected at concentrations of less than 0.16 CFUs/mL only more than 48 hours postinoculation. After implementation, 776 (0.35%) and 303 (0.77%) initial-positive results and 201 (0.09%) and 16 (0.04%) confirmed-positive results were obtained for pools and apheresis units, respectively, predominantly with Cutibacterium acnes. Other organisms included staphylococci, streptococci, Klebsiella oxytoca and Pseudomonas aeruginosa. One nonfatal reaction involving a 7-day pool contaminated with S. epidermidis occurred. Approximately, 1-in-1000 false-negative screening results were obtained during testing of outdated PCs. Approximately 1000 cocomponents associated with false-positive results were released into inventory. Combined PC outdating at Canadian Blood Services and hospitals was reduced from 18.9% to 13.1%. Conclusion Screening of 7-day PCs increased bacterial detection mainly of anaerobes and reduced outdating. The incidence of septic transfusion events has decreased approximately threefold. A longer surveillance period is needed to evaluate the value of anaerobic cultures and residual safety risk.

Background Hemolysis following the administration of intravenous immunoglobulin (IVIG) is an important adverse event (AE). While the monocyte monolayer assay (MMA) has been used to predict in vivo hemolysis when serologically incompatible blood may be transfused, it has also been shown to correlate with IVIG-associated hemolysis. In this study, the MMA was examined for its utility in assessing the risk of hemolysis after IVIG. Study design and methods Forty-two non-blood group O patients receiving high-dose IVIG (≥2 g/kg) were examined using an autologous and allogeneic MMA. Hemolysis was defined by a drop in hemoglobin of ≥1 g/L, a positive direct antiglobulin test (DAT) and eluate, and a decrease in haptoglobin or increase in lactate dehydrogenase and/or reticulocytes. Results Forty-two patients provided 50 assessable postinfusion samples, with hemolysis observed in 20 (40%) of cases. Autologous MMA using post-IVIG red blood cells significantly correlated with clinical outcomes when compared to allogeneic MMA (P = .0320 vs .5806, t test). No significant difference in receiver operating characteristics was observed when comparing autologous MMA testing against DAT for the diagnosis of IVIG-associated hemolysis. However, when using samples collected 5 to 10 days after receipt of high-dose IVIG, the autologous MMA had higher sensitivity than the DAT. Conclusion MMA testing with autologous monocytes collected 5 to 10 days after receipt of high-dose IVIG can be used for the diagnosis of IVIG-associated hemolysis and may be of particular value in cases in which the Day 5 to 10 DAT is negative.

Background Greater use of unrelated donors to support hematopoietic cell transplantation can be hampered by unavailability of registrants when identified as potential candidates for donation. Methods Multivariate analysis was performed to identify donor factors associated with availability for verification of human leukocyte antigen typing (VT) needed before donor activation. All VT requests for registrants on the Canadian Blood Services Stem Cell Registry between 1 January and 31 December 2018 were reviewed (n = 1358). Results Potential donors identified by transplant centers were categorized as available at the time of VT but ineligible for medical or other reasons (n = 130 and excluded from further analysis), available (n = 622) or unavailable (n = 566) due to scheduling, loss of interest, and/or inability to contact. With multivariate analysis, registrants who previously donated blood, those recruited online or from blood donation clinics, and a shorter interval between registration and VT request were significantly correlated with increased donor availability. Donor sex and geographic location, however, displayed no correlation. Conclusion Online registration and recruitment at whole blood donation centers should be enhanced to increase the availability of registrants at VT. More insight is needed to maintain registrant availability following community in-person recruitment events, especially if the interval between registration and activation is prolonged. Recruitment of male registrants who are well informed should not negatively impact availability.

BACKGROUND Transfusion medicine standards in Canada state that adult recipients can be transfused with cryoprecipitate of any ABO group, however, not all hospitals follow this guideline. There is a paucity of data on cryoprecipitate anti-A/B levels to reinforce standards. STUDY DESIGN AND METHODS Manual tube antibody titration was performed on 7 units of group O plasma and the corresponding cryosupernatant plasma and cryoprecipitate. IgG/IgM levels were determined by nephelometry. Additionally, 10 cryoprecipitate each from groups A, B, and O were similarly assessed. From the antibody titer distribution among these samples, the probability of making a pool of cryoprecipitate with a titer ≥1:100 was calculated using bootstrap analysis. RESULTS Anti-A/B titers in cryoprecipitate were equivalent to those in corresponding plasma; partitioning of anti-A/B activity into cryoprecipitate was not observed. Average IgM concentration was higher in cryoprecipitate than in plasma (P

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 employed, 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, USA) against 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% (PRNT50 ). 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. This article is protected by copyright. All rights reserved.

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

BACKGROUND The deferral for men who have sex with men (MSM) was reduced from a permanent deferral for MSM if even one time since 1977 to progressively shorter time deferrals of 5 years and 1 year in Canada. We assessed compliance with these deferrals and the impact on safety at Canadian Blood Services. STUDY DESIGN AND METHODS Three anonymous online compliance surveys of male whole blood donors were carried out before and after implementation of successive changes. HIV rates and incidence were monitored from January 1, 2011, to August 14, 2018. RESULTS Participation rates in the consecutive surveys were 49.7% before implementation, 36.3% after 5 years and 36.3% after 1 year. There was no difference before versus after implementation in male donors with MSM history in the past year (0.21%, 0.19%, 0.24%; p = 0.70). The percentage of eligible MSM donors increased (0.13%, 0.66%, 1.21%; p < 0.0001), with approximately 2500 eligible MSM donors with the 1-year deferral in place. HIV rates were less than 0.6 per 100,000 donations and unchanged after each policy change (p = 0.14 for trend). Incidence remained unchanged at 0.22 per 100,000 person-years before implementation, 0.54 per 100,000 after 5-year deferral, and no incident cases after 1-year deferral (p = 0.55). CONCLUSION Progressively shorter time deferrals had no impact on noncompliance of MSM with a male partner in the past year. Contrary to modeling predictions, shorter time deferrals had no impact on HIV rates or incidence. There was a modest increase in eligible MSM in the donor pool after each shorter time deferral. These results support the safety of reducing deferral periods for MSM.

Numerous studies point to the utility of blood cytokine measurements in the diagnosis and treatment of human disease. Advances in detection allow robust multiplex analysis. However, cytokines are present at low levels and are produced and act in complex networks which can remain active in stored blood. A major barrier to the routine use of cytokines as clinical biomarkers is sample management prior to analysis. Studies on cytokine stability under storage frequently use ‘spiked’ normal control plasma or serum to generate detectable levels of the cytokines of interest. These conditions may oversimplify the reality of clinically complex samples and provide limited information regarding optimal management of whole blood samples prior to plasma separation. Cytokine stability has also been addressed previously using plasma from normal individuals under different conditions of anticoagulant use, storage time and temperature of storage. No studies have as yet been undertaken to address cytokine stability in critically ill patients which may differ from normal, healthy individuals due to underlying cofounders such as inflammation. To address these issues, we subjected samples from five patients exhibiting an inflammatory disease state to three storage extremes which might be encountered in a clinical setting, prior to analysis of 40 cytokines. Blood drawn into EDTA or ACD anticoagulant was immediately separated and plasma stored at −80 °C. Matched samples were stored as follows; whole blood overnight at room temperature, or whole blood or plasma stored 10 days at 4 °C. We used equivalence testing to determine the similarity of stored cytokine values to baseline values. In ACD plasma, Eotaxin, IL-6, IL-11, IL-15, IP10, MDC, MCP-1 met equivalence to baseline in all storage conditions while for EDTA plasma stored 10 days at 4 °C EGF, FGF2, Fractalkine, G-CSF, IL-1β, IL-5, IL-6, IL-7, IL-11, IP-10, TGFα and TNFα showed equivalence to baseline measurements. Intraclass Correlation Coefficients (ICC) were calculated and the following cytokines showed good to excellent agreement across all 4 storage conditions: Eotaxin, IL-5, IL-6, IL-11, IL-13, IP-10, MCP-1 and TNFα when collected in EDTA, and Eotaxin, IL-5, IL-6, IL-11, IL12-p40, IL-15, IP-10 and MCP-1 when collected in ACD. Five plasma cytokines were identified as being the least stable in both ACD and EDTA: IL-7, IL-9, IL12p70, RANTES, sCD40L, while IL-1β was identified as unstable stored in ACD plasma. This study identified several clinically important cytokines that are remarkably stable in blood and plasma, and some that stored poorly. To our knowledge, this is the first cytokine storage study to use medically unwell patient samples and equivalence testing to evaluate the stability of measured cytokine values after storage.

Background and objectives In Canada, transfusion transmission risk of Human T-cell lymphotropic virus -I/II (HTLV) is addressed by universal leucoreduction and universal antibody testing. We aimed to estimate the risk with the current policy, if testing only first-time donors and if testing were stopped. Materials and methods Monte Carlo simulation was employed to estimate the proportion of red cell concentrate, random donor platelet and apheresis platelet units that would be released into inventory in each scenario (10 billion donors each). The model estimated the number of HTLV-positive donations not intercepted by testing, randomly assigned the number of HTLV particles/100 leucocytes using proportions from published data and randomly selected a postleucoreduction leucocyte count from quality control data. Units were considered infectious if ≥9 × 104 copies of HTLV provirus. Results With universal leucoreduction in place, the residual risk of releasing an HTLV potentially infectious unit with universal testing was 1 in 1·2 billion units (0, 1 in 55·9 million), with testing only first-time donors 1 in 7·1 million (0, 1 in 1·05 million) and with no testing 1 in 1·0 million (0, 1 in 178 600). The efficacy of leucoreduction was >99·5% (lower bound 95·7%) for all scenarios. Conclusion With universal leucoreduction in place, switching from universal testing to testing first-time donors would incur very low risk.

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 (

Background There are few studies investigating the effect of irradiation on red blood cells (RBCs) during storage. This study analyzed changes in in vitro quality of RBCs irradiated at several points during storage with the aim of providing evidence to support current maximum pre- and postirradiation storage limits. Study design and methods Each of seven participating centers produced four pools of 7 standard RBC units (SAGM, AS-3, or PAGGSM), which were then split back into 7 units. All units in a pool were from sex-matched blood donors. Every week during 6 weeks of refrigerated storage, 1 unit was irradiated, while 1 unit was not irradiated (control). Units were tested weekly for biochemical variables, morphology, and mechanical fragility. Results The earlier during storage that units were irradiated, the higher the hemolysis and K+ at end of storage. Irrespective of the timing of irradiation, there was a rapid increase in extracellular K+ , followed by a more gradual increase in hemolysis. ATP levels decreased faster in irradiated units and were reduced below accepted values if irradiated early. Irradiated female RBCs had an absolute lower hemolysis and K+ level compared to male RBCs at all time points. Conclusions The method of blood component manufacturing determined the absolute levels of hemolysis and potassium in irradiated and nonirradiated units, but did not influence the effect that timing of irradiation had on the in vitro quality characteristics. This study provides support for the current Council of Europe guidelines on the time limitations for the irradiation of RBCs.

BackgroundMultiple anti-SARS-CoV-2 immunoassays are available, but no gold standard exists. We assessed four assays using various methodological approaches to estimate SARS-COV-2 seroprevalence during the first COVID-19 wave in Canada.MethodsThis serial cross-sectional study was conducted using plasma samples from healthy blood donors between April-September 2020. Qualitative assessment of SARS-CoV-2 IgG antibodies was based on four assays: Abbott Architect SARS-Cov-2 IgG assay (target nucleocapsid) (Abbott-NP) and three in-house IgG ELISA assays (target spike glycoprotein (Spike), spike receptor binding domain (RBD), and nucleocapsid (NP)). Seroprevalence was estimated using multiple composite reference standards (CRS) and by a series of Bayesian Latent Class Models (BLCM) (using uninformative, weakly, and informative priors).Results8999 blood samples were tested. The Abbott-NP assay consistently estimated seroprevalence to be lower than the ELISA-based assays. Discordance between assays was common, 13 unique diagnostic phenotypes were observed. Only 32 samples (0.4%) were positive by all four assays. BLCM using uninformative priors predicted seroprevalence increased from 0.7% (95% credible interval (CrI); 0.4, 1.0%) in April/May to 0.8% (95% CrI 0.5, 1.2%) in June/July to 1.1% (95% CrI 0.7, 1.6) in August/September. Results from CRS were very similar to the BLCM. Assay characteristics varied considerably over time. Overall spike had the highest sensitivity (89.1% (95% CrI 79.2, 96.9%), while the sensitivity of the Abbott-NP assay waned from 65.3% (95% CrI 43.6, 85.0%) in April/May to 45.9% (95% CrI 27.8, 65.6) by August/September.DiscussionWe found low SARS-CoV-2 seroprevalence rates at the end of the first wave and estimates derived from single assays may be biased.SummaryMultiple anti-SARS-CoV-2 immunoassays are available, but no gold standard exists. We used four unique assays to estimate very low SARS-COV-2 seroprevalence during the first COVID-19 wave in Canada. Caution should be exercised when interpretating seroprevalence estimates from single assays.

BACKGROUND Effective donor skin disinfection is essential in preventing bacterial contamination of blood components with skin flora bacteria like Staphylococcus epidermidis. Cell aggregates of S. epidermidis (biofilms) are found on the skin and are resistant to the commonly used donor skin disinfectants chlorhexidine-gluconate and isopropyl alcohol. It has been demonstrated that essential oils synergistically enhance the antibacterial activity of chlorhexidine-gluconate. The objective of this study was to test plant-extracted essential oils in combination with chlorhexidine-gluconate or chlorhexidine-gluconate plus isopropyl alcohol for their ability to eliminate S. epidermidis biofilms. STUDY DESIGN AND METHODS The composition of oils extracted from Artemisia herba-alba, Lavandula multifida, Origanum marjoram, Rosmarinus officinalis, and Thymus capitatus was analyzed using gas chromatography-mass spectrometry. A rabbit model was used to assess skin irritation caused by the oils. In addition, the anti-biofilm activity of the oils used alone or in combination with chlorhexidine-gluconate or chlorhexidine-gluconate plus isopropyl alcohol was tested against S. epidermidis biofilms. RESULTS Essential oil concentrations 10%, 20%, and 30% were chosen for anti-biofilm assays, because skin irritation was observed at concentrations greater than 30%. All oils except for O. marjoram had anti-biofilm activity at these three concentrations. L. multifida synergistically enhanced the anti-biofilm activity of chlorhexidine-gluconate and resulted in the highest anti-biofilm activity observed when combined with chlorhexidine-gluconate plus isopropyl alcohol. Gas chromatography-mass spectrometry revealed that the main component contributing to the activity of L. multifida oil was a natural terpene alcohol called linalool. CONCLUSION The anti-biofilm activity of chlorhexidine-gluconate plus isopropyl alcohol can be greatly enhanced by L. multifida oil or linalool. Therefore, these components could potentially be used to improve blood donor skin disinfection.

BACKGROUND The platelet (PLT) storage lesion is in part caused by the collection and/or production process. Pathogen inactivation (PI) further accelerates its development leading to a reduced in vitro PLT functionality and hence quality. Although the treatment of PLT concentrates (PCs) with riboflavin and ultraviolet light PI should occur within 22 hours of collection, in this study the impact of treatment timing on in vitro PLT quality was investigated. STUDY DESIGN AND METHODS Apheresis PCs were PI treated on the day of production or on Days 1, 3, or 4 of storage or left untreated as control. A panel of in vitro variables was used to monitor quality throughout 7-day storage, including metabolism, PLT activation, and release of microparticles. Changes in phosphorylation profiles of proteins in the lysate and levels of PLT factor 4, thrombospondin, and epidermal growth factor (EGF) in the releasate were analyzed by immunoblots or enzyme-linked immunosorbent assay. RESULTS By Day 7 of storage, units illuminated on Day 4 showed a smaller impact of the PI process than units treated on the day of production or one day after on PLT quality such as PLT activation; metabolic activity; microvesicle and EGF release; and phosphorylation of p38, ERK, and HSP27. PCs treated on Day 3 of storage displayed an intermediate effect. CONCLUSION The timing of PI treatment of PCs influences in vitro PLT quality. Based on these results, timing recommendations should be reconsidered. If PI is applied, inventory management in blood banks might improve with a more flexible collection and treatment regime.

Staphylococcus epidermidis is a bacterium frequently isolated from contaminated platelet concentrates (PCs), a blood product used to treat bleeding disorders in transfusion patients. PCs offer an accidental niche for colonization of S. epidermidis by forming biofilms and thus avoiding clearance by immune factors present in this milieu. Using biochemical and microscopy techniques, we investigated the structural changes of the peptidoglycan (PG) and the biofilm matrix of S. epidermidis biofilms formed in whole-blood derived PCs compared to biofilms grown in glucose-supplemented trypticase soy broth (TSBg). Both, the PG and the biofilm matrix are primary mechanisms of defense against environmental stress. Here we show that in PCs, the S. epidermidis biofilm matrix is mainly of a proteinaceous nature with extracellular DNA, in contrast to the predominant polysaccharide nature of the biofilm matrix formed in TSBg cultures. PG profile studies demonstrated that the PG of biofilm cells remodels during PC storage displaying fewer muropeptides variants than those observed in TSBg. The PG muropeptides contain two chemical modifications (amidation and O-acetylation) previously associated with resistance to antimicrobial agents by other staphylococci. Our study highlights two key structural features of S. epidermidis that are remodeled when exposed to human platelets and could be used as targets to reduce septic transfusions events., CONACyT provided additional funding

BACKGROUND The optimal method of providing transfusion medicine (TM) education has not been determined. Transfusion Camp was established in 2012 at the University of Toronto as a centrally delivered TM education program for postgraduate trainees. The impact of Transfusion Camp on knowledge, attitudes, and self-reported behavior was evaluated. METHODS Didactic lectures (delivered locally, by webinar, or recorded) and locally facilitated team-based learning seminars were delivered over 5 days during the academic year to 8 sites: 7 in Canada and 1 in the United Kingdom. Knowledge assessment using a validated 20-question multiple-choice exam was conducted before and after Transfusion Camp. Attitudes and self-reported behavior were collected through a survey. RESULTS Over 2 academic years (July 2016 to June 2018), 390 trainees from 16 different specialties (predominantly anesthesia, 41%; hematology, 14%; and critical care, 7%) attended at least 1 day of Transfusion Camp. The mean pretest score was 10.3 of 20 (±2.9; n = 286) compared with posttest score of 13.0 (±2.8; n = 194; p < 0.0001). Lower pretest score and greater attendance (4-5 days compared with 1-3 days) were associated with larger improvement in posttest score; delivery format, specialty, and postgraduate year were not. Trainees reported an improvement in self-rated abilities to manage TM scenarios; 95% rated TM knowledge as very or extremely important in providing patient care; and 81% indicated that they had applied learning from Transfusion Camp into clinical practice. CONCLUSIONS Transfusion Camp increased TM knowledge, fostered a positive attitude toward TM, and enabled a self-reported positive impact on transfusion practice in postgraduate trainees. It is a novel and scalable approach to delivering TM education.

A 95% confidence interval (CI) of the mean is a range with an upper and lower number calculated from a sample. Because the true population mean is unknown, this range describes possible values that the mean could be. If multiple samples were drawn from the same population and a 95% CI calculated for each sample, we would expect the population mean to be found within 95% of these CIs. CIs are sensitive to variability in the population (spread of values) and sample size. When used to compare the means of two or more treatment groups, a CI shows the magnitude of a difference between groups. This is helpful in understanding both the statistical significance and the clinical significance of a treatment. In this article we describe the basic principles of CIs and their interpretation.

Background and Objectives Quality control (QC) data collected by blood services are used to monitor production and to ensure compliance with regulatory standards. We demonstrate how analysis of quality control data can be used to highlight the sources of variability within red cell concentrates (RCCs). Materials and Methods We merged Canadian Blood Services QC data with manufacturing and donor records for 28 227 RCC between June 2011 and October 2014. Units were categorized based on processing method, bag manufacturer, donor age and donor sex, then assessed based on product characteristics: haemolysis and haemoglobin levels, unit volume, leucocyte count and haematocrit. Results Buffy-coat method (top/bottom)-processed units exhibited lower haemolysis than units processed using the whole-blood filtration method (top/top). Units from female donors exhibited lower haemolysis than male donations. Processing method influenced unit volume and the ratio of additive solution to residual plasma. Conclusions Stored red blood cell characteristics are influenced by prestorage processing and donor factors. Understanding the relationship between processing, donors and RCC quality will help blood services to ensure the safety of transfused products.

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.

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.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.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.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.

The inability to effectively treat biofilm-related infections is a major clinical challenge. This has been attributed to the heightened antibiotic tolerance conferred to bacterial cells embedded within biofilms. Lytic bacteriophages (phages) have evolved to effectively infect and eradicate biofilm-associated cells. The current study was designed to investigate the ability of phage treatment to enhance the activity of antibiotics against biofilm-forming Staphylococcus aureus. The biofilm positive S. aureus strain ATCC 35556, the lytic S. aureus phage SATA-8505, and five antibiotics (cefazolin, vancomycin, dicloxacillin, tetracycline, and linezolid), used to treat S. aureus infections, were tested in this study. The ability of the SATA-8505 phage to augment the effect of these antibiotics against biofilm-associated S. aureus cells was assessed by exposing them to one of the five following treatment strategies: (i) antibiotics alone, (ii) phage alone, (iii) a combination of the two treatments simultaneously, (iv) staggered exposure to the phage followed by antibiotics, and (v) staggered exposure to antibiotics followed by exposure to phage. The effect of each treatment strategy on biofilm cells was assessed by enumerating viable bacterial cells. The results demonstrate that the treatment of biofilms with either SATA-8505, antibiotics, or both simultaneously resulted in minimal reduction of viable biofilm-associated cells. However, a significant reduction [up to 3 log colony forming unit (CFU)/mL] was observed when the phage treatment preceded antibiotics. This effect was most pronounced with vancomycin and cefazolin which exhibited synergistic interactions with SATA-8505, particularly at lower antibiotic concentrations. This in vitro study provides proof of principle for the ability of phages to augment the activity of antibiotics against S. aureus biofilms. Our results also demonstrate that therapeutic outcomes can be influenced by the sequence in which these therapeutic agents are administered, and the nature of their interactions. Further investigation into the interactions between lytic phages and antibiotics against various biofilm-forming organisms is important to direct future clinical translation of efficacious antibiotic–phage combination therapeutic strategies.

A p-value is a number between 0 and 1 that is extremely useful in interpreting research results. Using comparison of the means of two samples as an example, a p-value

BACKGROUND After introduction of a closed-system cell processor, the effect of this product change on safety, efficacy, and utilization of washed red blood cells (RBCs) was assessed. STUDY DESIGN AND METHODS This study was a pre-/postimplementation observational study. Efficacy data were collected from sequentially transfused washed RBCs received as prophylactic therapy by β-thalassemia patients during a 3-month period before and after implementation of the Haemonetics ACP 215 closed-system processor. Before implementation, an open system (TerumoBCT COBE 2991) was used to wash RBCs. The primary endpoint for efficacy was a change in hemoglobin (Hb) concentration corrected for the duration between transfusions. The primary endpoint for safety was the frequency of adverse transfusion reactions (ATRs) in all washed RBCs provided by Canadian Blood Services to the transfusion service for 12 months before and after implementation. RESULTS Data were analyzed from more than 300 RBCs transfused to 31 recipients before implementation and 29 recipients after implementation. The number of units transfused per episode reduced significantly after implementation, from a mean of 3.5 units to a mean of 3.1 units (p

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 US 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, Quebec, New Brunswick, and Nova Scotia) near endemic US 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 Quebec, two in New Brunswick). From active tick surveillance, six of 361 ticks in Manitoba were positive (1.7%), three of 641 (0.5%) in Quebec, 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.

Mandatory predonation reading materials inform donors about risk factors for transmissible disease, possible complications of donation and changes to the donation process. We aimed to assess the attention to predonation reading materials and factors which may affect attention.A national survey in 2008 of 18,108 blood donors asked about self-assessed attention to reading the materials. In face-to-face interviews, 441 donors completed additional questions about reading the materials and a literacy test. Qualitative interviews of 27 donors assessed their approach to reading.In the national survey, most of the first-time donors said they read all or most of the materials (90.9% first-time vs. 57.6% repeat donors, P0.001) and 66% vs. 23.1% reported reading them carefully (P0.001). In face-to-face interviews comparing those who read materials carefully, skimmed or did not read, most knew that donors are informed of positive transmissible disease test results (97.1%, 95.5, 98.0 P0.05), but fewer recalled seeing the definition of sex (77.2%, 56.9, 24.2 P0.001). Literacy was poor (30.5% frustration level, 60.3% instructional, 9.2% independent) but similar when those who read materials carefully, skimmed or did not read were compared (P0.05). Qualitative interviews showed that donors are reluctant to read any more than necessary and decide based on perceived importance or relevance.Attention to predonation reading materials tends to be better among first-time donors. The effectiveness is limited by low motivation to read, especially for repeat donors, as well as poor literacy.

BACKGROUND To investigate the long-term consequences of repeated plasmapheresis on donor health, their donation histories and demographic data were reviewed to determine the frequency of development of monoclonal (Mc) gammopathies or other gamma globulin abnormalities (OGGAs). STUDY DESIGN AND METHODS Samples from apheresis plasma donors collected at Canadian Blood Services were tested initially and every 4 months for total protein (TP) followed by serum protein electrophoresis (SPE). Out-of-range samples or those showing abnormal band patterns were forwarded to a hospital laboratory for additional investigation. RESULTS Of 52,972 donors who donated 471,446 apheresis plasmas over 9 years, 89,490 samples were sent for TP and SPE testing. Of 3005 samples forwarded for further investigation, abnormal immunofixation electrophoresis (IFE) results were found in 209 (0.4%) donors, 85 from first-time (FT) and 124 from repeat (RPT) plasma donors during participation in the program. There were 167 donors with Mc gammopathies (73 FT, 94 RPT) and 42 with OGGAs (12 FT, 30 RPT). FT or RPT donors with Mc gammopathies or OGGAs were significantly older than those with normal SPEs. RPT donors with Mc gammopathies or OGGAs also had a longer donation period than donors with normal SPEs. CONCLUSIONS The incidence of Mc gammopathies (2.41 per 1000 donors) did not significantly increase from 2004 to 2012. Older donors had a higher incidence of Mc gammopathies and longer donation periods than their healthy counterparts. Overall, gammopathy rates were below those reported over the same age range in the general population.

There are few studies investigating the effect of irradiation on red blood cells (RBCs) during storage. This study analyzed changes in in vitro quality of RBCs irradiated at several points during storage with the aim of providing evidence to support current maximum pre- and postirradiation storage limits.Each of seven participating centers produced four pools of 7 standard RBC units (SAGM, AS-3, or PAGGSM), which were then split back into 7 units. All units in a pool were from sex-matched blood donors. Every week during 6 weeks of refrigerated storage, 1 unit was irradiated, while 1 unit was not irradiated (control). Units were tested weekly for biochemical variables, morphology, and mechanical fragility.The earlier during storage that units were irradiated, the higher the hemolysis and KThe method of blood component manufacturing determined the absolute levels of hemolysis and potassium in irradiated and nonirradiated units, but did not influence the effect that timing of irradiation had on the in vitro quality characteristics. This study provides support for the current Council of Europe guidelines on the time limitations for the irradiation of RBCs.

BACKGROUND Blood transfusions and fractionated products are not without risk and may lead to acute and long-term adverse events. The objective of this study was to evaluate the appropriateness of usage of frozen plasma (FP), cryoprecipitate (CRYO), and recombinant factor VIIa (rVIIa) in a pediatric setting. METHODS All orders for FP, CRYO, and rVIIa were prospectively audited over 6 weeks. Data collected included demographics, laboratory values, indication, and adverse reactions. The appropriateness of each order was independently evaluated using adjudication criteria rated by two hematologists. RESULTS Two hundred sixty-five products were ordered; 67% of the orders were issued to operating rooms or intensive care units. The most common indication for all products was cardiac surgery. FP was ordered as fluid replacement (15/215; 7%) to correct abnormal coagulation tests (23/215; 11%) and for patients with minor or no bleeding (111/242; 46%). FP was more likely to alter the international normalized ratio (INR) if the INR was over 2.0 (P