Has the frequency of ABO RhD blood groups in Australian blood donors changed as a result of the removal of the variant Creutzfeldt-Jakob disease-based deferral?

BACKGROUND AND OBJECTIVES: Until 25 July 2022, Australians who had spent more than 6 months in the United Kingdom or territories between 1980 and 1996 were deferred from blood donation due to the risk of variant Creutzfeldt-Jakob disease. Removal of this geography-based donor deferral on RhD-negative blood availability has not been reported. MATERIALS AND METHODS: All donors who donated at least once from 25 July 2022 to 25 July 2023 were included. UK donor status, first-time donor and ABO RhD data were extracted from the National Blood Management System. RESULTS: Data from 566,447 blood donors with a valid ABO RhD result were analysed. Of these, 34,560 were new or returning lapsed donors following removal of the UK donor deferral. The median age [range] in years for all donors was 43 [75] with UK donors being older 53 [70]. There was a higher prevalence of RhD-negative status in UK donors (20.2%) compared with first-time blood donors (15.7%). CONCLUSION: UK donors were generally older, female and more likely to be RhD-negative. Although UK donors provided a boost to RhD-negative blood collections, the overall prevalence of ABO RhD blood groups in the total Australian blood donor panel remained similar to previous estimates.

Association Between Blood Donor Demographics and Post-injury Multiple Organ Failure after Polytrauma.

OBJECTIVE: To test the hypothesis that blood donor demographics are associated with transfused polytrauma patients' post-injury multiple organ failure (MOF) status. SUMMARY OF BACKGROUND DATA: Traumatic shock and MOF are preventable causes of death and post-traumatic hemorrhage is a frequent indication for transfusion. The role of blood donor demographics on transfusion recipients is not well known. METHODS: A log-linear analysis accounting for the correlated structure of the data based on our prospective MOF database was utilized. Tests for trend and interaction were computed using a likelihood ratio procedure. RESULTS: A total of 229 critically injured transfused trauma patients were included, with 68% of them being males and a mean age of 45 years. On average 10 units of blood components were transfused per patient. A total of 4379 units of blood components were donated by donors aged 46 years on average, 74% of whom were males. Blood components used were red blood cells (47%), cryoprecipitate (29%), fresh frozen plasma (24%), and platelets (less than 1%). Donor-recipient sex mismatched red blood cells transfusions were more likely to be associated with MOF ( P = 0.0012); fresh frozen plasma and cryoprecipitate recipients were more likely to experience MOF when transfused with a male (vs female) component ( P = 0.0014 and <0.0001, respectively). Donor age was not significantly associated with MOF for all blood components. CONCLUSIONS: Blood components donor sex, but not age, may be an important factor associated with post-injury MOF. Further validation of our findings will help guide future risk mitigation strategies specific to blood donor demographics.

Absence of correlation between ABO Rh(D) blood group and neutralizing antibody titers in SARS-CoV-2 convalescent plasma donors.

BACKGROUND: Several studies have described associations between ABO blood group and SARS-CoV-2 infection severity in hospitalized patients where group A individuals are over-represented and group O individuals may have a lower infection rate. In convalescent individuals, group B blood donors have higher neutralizing SARS-CoV-2 antibody titers. We analyzed whether there was any correlation of ABO Rh(D) blood group with SARS-CoV-2 infection and with neutralizing antibodies in Australian convalescent plasma (CP) donors. STUDY DESIGN AND METHODS: ABO Rh(D) distribution and demographics of CP donors (n = 765) were compared with the total blood donor panel (n = 488,028), plasmapheresis donors (n = 203,176) and whole blood donors (n = 282,437) from 2020. The presence of neutralizing antibodies in CP donors was measured using the Vero E6 cell microneutralization assay. RESULTS: The distribution of ABO group in CP donors compared to the total donor panel was not significantly different (p = .177). There were significantly more group AB donors in the plasmapheresis subset (p = .005) and group O individuals were over-represented in the whole blood donor subset (p < .0001). There was no significant difference in neutralizing antibody levels among CP donors with differing ABO blood groups (p = .872). CONCLUSION: ABO Rh(D) blood group distribution was not found to be significantly different between convalescent plasma donors and general blood donors in our large sample group. Inherent blood donor selection biases associated with clinical demand accounted for some differences within CP donors. The levels of SARS-CoV-2 neutralizing antibodies were also not significantly associated with ABO Rh(D) group.

The distribution of ABO RhD blood groups in Australia, based on blood donor and blood sample pathology data.

OBJECTIVE: To determine the distribution of ABO RhD blood groups in Australia in 2019. DESIGN: Retrospective analysis of blood group data for blood donors (Australian Red Cross Lifeblood National Blood Management System) and for people whose blood type was determined in samples submitted for analysis by hospital-based or private pathology agencies. SETTING: All Australian states and territories, 1 January - 31 December 2019. MAIN OUTCOME MEASURES: Proportions of donors and patients, by ABO blood group and RhD status. These proportions were compared with published data for 1993-94 first-time blood donors. RESULTS: A total of 1 318 751 valid ABO RhD blood group results were provided by 28 of 41 invited pathology agencies (including 245 of 324 approved health providers, 76%). Valid ABO RhD data were available for 490 491 blood donors, including 103 798 first-time donors (21.2%). Blood group prevalence based on samples typed by pathology services was O RhD+, 38.4%; O RhD-, 6.5%; A RhD+, 32.0%; A RhD-, 5.6%; B RhD+, 11.8%; B RhD-, 1.5%; AB RhD+, 3.7%; and AB RhD-, 0.5% (totals: RhD+, 85.9%; RhD-, 14.1%). The distribution based on typing of first-time blood donors was similar. The overall proportion of RhD+ first-time donors rose from 81% in 1993-94 to 83.8% in 2019; the proportion of groups B and AB RhD+ RBC units issued declined from 9.8% in 2010-11 to 6.9% of all RBC units in 2019-20, while that of O RhD- RBC units increased from 11.7% to 17.4%. CONCLUSION: Our national assessment of ABO RhD prevalence in Australia provides updated information for re-evaluating blood and blood product collection and holdings in light of changes in population demographic characteristics.

Seroprevalence of SARS-CoV-2-specific antibodies in Sydney after the first epidemic wave of 2020.

OBJECTIVES: To estimate SARS-CoV-2-specific antibody seroprevalence after the first epidemic wave of coronavirus disease 2019 (COVID-19) in Sydney. SETTING, PARTICIPANTS: People of any age who had provided blood for testing at selected diagnostic pathology services (general pathology); pregnant women aged 20-39 years who had received routine antenatal screening; and Australian Red Cross Lifeblood plasmapheresis donors aged 20-69 years. DESIGN: Cross-sectional study; testing of de-identified residual blood specimens collected during 20 April - 2 June 2020. MAIN OUTCOME MEASURE: Estimated proportions of people seropositive for anti-SARS-CoV-2-specific IgG, adjusted for test sensitivity and specificity. RESULTS: Thirty-eight of 5339 specimens were IgG-positive (general pathology, 19 of 3231; antenatal screening, 7 of 560; plasmapheresis donors, 12 of 1548); there were no clear patterns by age group, sex, or location of residence. Adjusted estimated seroprevalence among people who had had general pathology blood tests (all ages) was 0.15% (95% credible interval [CrI], 0.04-0.41%), and 0.29% (95% CrI, 0.04-0.75%) for plasmapheresis donors (20-69 years). Among 20-39-year-old people, the age group common to all three collection groups, adjusted estimated seroprevalence was 0.24% (95% CrI, 0.04-0.80%) for the general pathology group, 0.79% (95% CrI, 0.04-1.88%) for the antenatal screening group, and 0.69% (95% CrI, 0.04-1.59%) for plasmapheresis donors. CONCLUSIONS: Estimated SARS-CoV-2 seroprevalence was below 1%, indicating that community transmission was low during the first COVID-19 epidemic wave in Sydney. These findings suggest that early control of the spread of COVID-19 was successful, but efforts to reduce further transmission remain important.

Understanding the demand for phenotyped red blood cell units and requests to perform molecular red blood cell typing for Australian patients.

BACKGROUND: Australian Red Cross Lifeblood has seen a 50 % increase in demand for phenotyped red blood cell (RBC) units between 2016-2018 and a 30 % increase in demand in 2018 to perform molecular RBC typing on patient samples. Lifeblood conducted a survey to understand transfusion laboratory practices for requesting patient phenotyping and/or molecular RBC typing and for selecting phenotyped RBC units in various patient groups. STUDY DESIGN AND METHODS: An electronic Qualtrics survey form was sent to 296 transfusion laboratories with questions designed to understand the practice of selecting phenotyped RBC units and reasons for requesting extended serology or molecular RBC typing. RESULTS: 49 (16.6 %) transfusion laboratories provided data. Reasons to request extended phenotyping and/or molecular RBC typing for patients included; chronic transfusion (n = 31 laboratories), sickle cell disease (n = 25), Thalassemia (n = 23), requirement for anti-CD38 or other MAB therapy (n = 23) or Myelodysplasia (n = 22). Forty-seven transfusion laboratories provided responses with reasons for requesting molecular RBC typing which included: predicting phenotype in patients with multiple antibodies (n = 31), prior to administering anti-CD38 or other MAB therapies (n = 29), for pregnancy related transfusions (n = 28) or for confirming the phenotype of recently transfused patients (n = 18). CONCLUSION: Transfusion laboratory practices indicated that phenotyped RBC units were selected for patients requiring chronic transfusion support and/or undergoing MAB therapy. Requests for molecular RBC typing occurred for more complex patient requirements where serological investigations were not suitable or possible due to reagent restrictions.

Evaluation of a sterile surgical skin marker to indicate the optimal vein for venepuncture in the blood donation setting.

BACKGROUND AND OBJECTIVES: Phlebotomy is a central task for blood donation; however, not all blood donors have veins that are easy to see or feel. This study aimed to determine whether use of a surgical skin marker to highlight the donors' vein location and direction prior to venepuncture increased blood donation success. METHODS: All blood donors who participated in this study were eligible to donate according to Australian guidelines. Ten donor centres with phlebotomy success rates <95% were selected. A randomized cluster trial design assigned five sites to test the skin marking device and five sites as controls. Single-use sterile Gentian violet skin marker pens were used to mark donors' veins. Phlebotomy site skin bacterial load after using the skin marking device was tested on a subset of 100 donors. Phlebotomy success rates and donor adverse events were recorded. RESULTS: Of the control donors, 6993 had successful phlebotomies and 225 failed. Of the skin marker donors, 6998 had successful phlebotomies and 248 failed. No statistically significant differences in phlebotomy success were found between the two groups (OR: 0·91, 96·4% CI [96·0, 96·8], P-value 0·348). CONCLUSION: The use of skin marker pens did not increase overall phlebotomy success rate. There was no increase in phlebotomy site skin bacterial load, and amendments to standard skin disinfection techniques were not required. Blood donors were not concerned about the pen mark on their arms. Generally, staff indicated that the markers may be valuable to assist with phlebotomies for donors with difficult or deep veins.

Comparison of group O Rh(D)- red blood cell use in pregnant women across hospitals of various sizes and obstetric capabilities prior to the introduction of patient blood management guidelines.

BACKGROUND: O Rh(D)- red blood cell (RBC) units can generally be transfused to most patients regardless of their ABO blood type and are frequently used during emergency situations. Detailed usage patterns of O Rh(D)- RBC units in obstetric populations have not been well characterised. With the introduction of patient blood management guidelines, historical usage patterns are important for providing comparative data. AIMS: To determine how the use of O Rh(D)- RBC units in pregnant women differs between hospitals of different sizes and obstetric capabilities prior to patient blood management guidelines. METHODS: Data from 67 New South Wales public hospital blood banks were linked with hospital and perinatal databases to identify RBC transfusions during pregnancy, birth and postnatally between July 2006 and December 2010. RBC transfusions were divided into O Rh(D)- or other blood types. Hospitals were classified according to birth volume, obstetric capability and location, with transfusions classified by timing and diagnosis. RESULTS: Of the 12 078 RBC units transfused into pregnant women, 1062 (8.8%) were O Rh(D)-. Higher use of O Rh(D)- RBC units was seen in antenatal transfusions, preterm deliveries and in regional or smaller hospitals. There was wide variation in rates of O Rh(D)- RBC transfusion among hospitals. CONCLUSIONS: The rate of O Rh(D)- RBC unit use in obstetrics was lower during the period assessed than the nationally reported usage. It is encouraging that O Rh(D)- RBCs were more commonly used in emergency or specialised situations, or in facilities where holding a large blood inventory is not feasible.

Evaluation of a tool to score donor vein suitability for blood donation.

BACKGROUND AND OBJECTIVES: Phlebotomy is a central task for whole blood donation, yet there are no published standards regarding systematic donor vein assessment or the impact of vein quality on successful blood donation. Blood donation failures and related adverse events are highly predictive of donors not returning for future blood donation. A specific blood donation vein scoring tool was assessed to measure donor vein suitability for whole blood collection and investigate the correlation of the donor's veins with donation outcomes. MATERIALS AND METHODS: The vein assessment tool consisted of three questions using a 5-point Likert-type scale to measure responses. Two phlebotomists performed blinded assessments of each donor's veins on each arm using the tool. The individual measures were then aggregated to provide a total vein score out of 12. Inter-rater reliability of the vein score tool was assessed by calculating the intraclass correlation coefficient for absolute agreement. RESULTS: Fifty-seven phlebotomists across four fixed blood donation centres performed paired vein assessments on 553 blood donors. The intraclass correlation coefficient indicated moderate inter-rater reliability was achieved. The median scores for viable donations were 10, for non-viable donations were 6·5 and for failed phlebotomies were 4. Donation histories of donors with lower vein scores indicated lower success during blood donation. CONCLUSION: The vein score tool appears to be predictive of a successful donation outcome, however, since there was not a suitably high correlation between the scores of the two assessors, further refinement of the tool will be required prior to wider use.

Mortality and hospital readmissions in the first year of life after intra-uterine and neonatal blood product transfusions: A population data linkage study.

AIM: Blood product transfusions are a potentially life-saving therapy for fetal and neonatal anaemia, but there is limited population-based research on outcomes. We aimed to describe mortality, readmission and average hospital stay in the first year of life for infants with or without intra-uterine or neonatal blood product transfusions. METHODS: Linked birth, hospital and deaths data from New South Wales, Australia (January 2002-June 2014) were used to identify singleton infants (≥23 weeks' gestation, surviving to 29 days; n = 1 089 750) with intra-uterine or neonatal transfusion or no transfusion. Rates of mortality and readmission in the first year (29-365 days) and days in hospital were calculated. RESULTS: Overall, 68 (0.06/1000) infants had experienced intra-uterine transfusion and 4332 (3.98/1000) neonatal transfusion. Transfusion was more common among those born at earlier gestational ages requiring invasive ventilation. Mortality, readmissions and average days in hospital were higher among transfused than non-transfused infants. Over half of infants with intra-uterine and neonatal transfusion had ≥1 readmission in the first 29-365 days (55.9 and 51.8%, respectively), and around a quarter had ≥2 (20.6 and 28.5%, respectively) compared with 15.3% with ≥1 and 3.5% with ≥2 in the non-transfused group. CONCLUSION: Infants with a history of blood product transfusion, particularly those needing a neonatal transfusion, had higher mortality and more frequent contact with the hospital system in the first year of life than those infants with no history of transfusion.

An analysis on the fate of a selection of blood products derived from cytomegalovirus-seronegative donors at three tertiary referral hospitals in Australia.

BACKGROUND: Supply of cytomegalovirus (CMV)-seronegative blood products in Australia is an ongoing challenge. Requests for CMV-negative products are increasing with prediction that the demand will exceed supply by 2019. Clinical information evaluating how these products are being utilized by health providers within Australia is limited. This study aimed to identify indications for use of CMV-negative blood products and gather data to support possible practice change. STUDY DESIGN AND METHODS: All CMV-negative products issued to three tertiary Australian hospitals from May 1, 2016, to May 31, 2016, were identified (n = 1219). This equated to 1044 red blood cell units and 175 platelet units. Data were collected on the fate of each unit. Information collected included the indication and urgency of transfusion, reason for discard, product age, and recipient CMV immunoglobulin G status. RESULTS: Of the units issued during the audit period, 32 (2.6%) were discarded by the hospitals. Transfusion data were collected on 411 units. Of these, 136 (33.1%) were transfused to CMV-positive recipients, in most cases for hematology indications, and 67 units (16.3%) were transfused to CMV-negative requiring recipients. A total of 144 (35%) CMV-negative units were selected based on their irradiation status. Other reasons for the selection of CMV-negative units included product close to expiry (n = 134, 32.6%) or specific patient phenotype requirements (n = 31, 7.5%). CONCLUSION: In this study, the majority of CMV-negative blood products were not used for CMV-negative requiring recipients. Alterations to inventory management would be advantageous to ensure continued supply for CMV-negative requiring recipients.

The use of historical platelet counts from blood donors to program apheresis platelet donation: An Australian perspective.

BACKGROUND: For Australian apheresis platelet donations, in-centre haematology analysers provided the platelet count used to program the platelet collection machines. When the haematology analysers were not functional, historical platelet counts from previous donations were used. This study aimed to confirm that the routine use of historical platelet counts for programming apheresis collection machines would maintain platelet yields within the donated units and that haematology analysers could be removed. STUDY DESIGN: A staggered implementation for the routine use of mean historical platelet counts to program apheresis platelet collection machines was conducted. The donors' full blood counts following donation were tested centrally for comparison to the historical mean. The component yields when using on-the-day platelet counts to program platelet collection were compared with those collected using historical platelet counts. For historical platelet counts to be deemed successful, the target was for 90% of the mean historical donor platelet counts to have less than 20% variance from the on-the-day platelet count. RESULTS: Over 96% of the mean historical platelet counts were within 20% variance of the platelet count on the day of donation. The component yield (platelet count x109 cell/unit) before analyser removal was 273.3 ±â€¯32.0 (n = 2639) and post-removal was 282.8 ±â€¯38.8 (n = 2689). CONCLUSION: The removal of haematology analysers from donor centres and replacement with mean historical platelet counts was successful in maintaining platelet yields. Replacement of the haematology analysers with historical platelet counts simplified regulatory compliance, reduced staff workload and costs associated with analyser registration.

A national review of the clinical use of group O D- red blood cell units.

BACKGROUND: There has been an international decline in the demand for red blood cell (RBC) units. In Australia, there has been a 21% reduction in demand between 2012 and 2015. In contrast, the demand for the "universal" group O D- RBC units is in fact proportionally increasing. STUDY DESIGN AND METHODS: The clinical use of the entire O D- RBC distribution for a 5-week period throughout Australia was reviewed. Fate data on each unit issued (n = 9733) were collected that included the indication and urgency of transfusion, reason for discard, component age, and patient demographics. RESULTS: A total of 74% of audit forms were returned (n = 7143). The national discard rate of issued units was 7.9%. A total of 6387 units were transfused into an estimated total of 3008 patients (55% males) with median patient age of 67 years and median RBC age of 21 days. Forty-seven percent were transfused to group O D- patients. A total of 17.4% were chosen for specific phenotype requirements, 24.5% of units were transfused close to expiry, and 24.5% were transfused into patients of other ABO groups. CONCLUSION: The data appear broadly representative of the current transfusion and inventory management practices surrounding the use of group O D- RBC units. Strategies to reduce O D RBC demand include reevaluation of inventory holdings particularly at smaller centers, increasing the panel of phenotyped RBC units across all ABO groups, more regular rotation of units between hospitals to minimize time expiry, and continuing education for promoting transfusion of ABO-identical RBC units.

A DNA Circuit for IsomiR Detection.

A synthetic DNA oligonucleotide has been programmed to function as a biological circuit to detect 5'-IsomiRs. The circuit consists of two integrated DNA switches. The first is "activated" when a DNA probe is enzymatically modified by a reverse transcriptase that incorporates nucleotides complementary to the 5'-region of a microRNA (miRNA). Addition of the correct number and sequence of nucleotides enables the probe to assemble into an asymmetric DNA hairpin. The reconfigured hairpin probe then primes an internal polymerisation reaction, resulting in the synthesis of a symmetrical DNA hairpin. This activates the second switch, which then initiates the amplification of reverse-transcribed miRNA through a continuous cycle of DNA nicking and polymerisation. The DNA circuit enables sensitive and rapid detection of femtomoles of a miRNA transcript under isothermal conditions.

The prevalence of selected clinically significant red blood cell antigens among Australian blood donors.

Red blood cell (RBC) transfusion can cause some patients to form antibodies to RBC antigens when RBC phenotypes do not match that of the blood donor. Transfusion practitioners can order phenotyped RBC units for patients with known RBC antibodies or those who are at risk of forming them. However, with increasing demand for phenotyped RBC units, contemporary data on antigen prevalence is required to manage the changing supply. A total of 490,491 blood donors, including 103,798 (21.2%) first-time blood donors, from 2019 were analysed for the prevalence of selected clinically relevant blood group antigens. Prevalence of the phenotype R1R1 (D+ C+ E- c- e+) increased from the previous estimate of 17.3% to 24.0% in first-time blood donors. The prevalence of R1r (D+ C+ E- c+ e+) decreased from 35.3% to 30.8%. R1R1 was more common in blood donors born in Asia or the Middle East. The prevalence of Fy(a-b-) in donors where Fy antigens were tested was 0.2%. Of these, 71.8% stated their region of birth as Africa. The prevalence of Jk(a-b-) is 0.01% in donors where the Jk antigens were tested with region of birth stated as either Oceania or Asia. The increasing prevalence of the c-negative phenotype in R1R1 individuals is associated with the changing demographics of the Australian community. For R1R1 individuals with childbearing potential, the transfusion of RhD negative blood, which is usually c-positive, may increase the possibility of haemolytic disease of the fetus and newborn during pregnancy. Continued diversification of the Australian blood donor panel will support having the appropriate phenotyped RBC units available.

Seroprevalence of Japanese encephalitis virus-specific antibodies in Australia following novel epidemic spread: protocol for a national cross-sectional study.

INTRODUCTION: Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus that causes encephalitis and other morbidity in Southeast Asia. Since February 2022, geographically dispersed JEV human, animal and vector detections occurred on the Australian mainland for the first time. This study will determine the prevalence of JEV-specific antibodies in human blood with a focus on populations at high risk of JEV exposure and determine risk factors associated with JEV seropositivity by location, age, occupation and other factors. METHOD: Samples are collected using two approaches: from routine blood donors (4153 samples), and active collections targeting high-risk populations (convenience sampling). Consent-based sampling for the latter includes a participant questionnaire on demographic, vaccination and exposure data. Samples are tested for JEV-specific total antibody using a defined epitope-blocking ELISA, and total antibody to Australian endemic flaviviruses Murray Valley encephalitis and Kunjin viruses. ANALYSIS: Two analytic approaches will occur: descriptive estimates of seroprevalence and multivariable logistic regression using Bayesian hierarchical models. Descriptive analyses will include unadjusted analysis of raw data with exclusions for JEV-endemic country of birth, travel to JEV-endemic countries, prior JEV-vaccination, and sex-standardised and age-standardised analyses. Multivariable logistic regression will determine which risk factors are associated with JEV seropositivity likely due to recent transmission within Australia and the relative contribution of each factor when accounting for effects within the model. ETHICS: National Mutual Acceptance ethical approval was obtained from the Sydney Children's Hospitals Network Human Research Ethics Committee (HREC). Local approvals were sought in each jurisdiction. Ethical approval was also obtained from the Australian Red Cross Lifeblood HREC. DISSEMINATION: Findings will be communicated to participants and their communities, and human and animal health stakeholders and policy-makers iteratively and after final analyses. Understanding human infection rates will inform procurement and targeted allocation of limited JEV vaccine, and public health strategies and communication campaigns, to at-risk populations.

Patient-reported outcomes of serum eye drops manufactured from Australian blood donations and packaged using Meise vials.

Introduction: Serum eye drops (SED) are an effective treatment for dry eye syndrome. However, autologous serum collection can have challenges. Patient-tailored (allogeneic) SED (PT-SED) can be made from healthy blood donors. Australian Red Cross Lifeblood has manufactured both autologous SED (Auto-SED) and PT-SED and, in May 2021, introduced Meise vial packaging. This study aimed to explore SED patient-reported outcomes and vial packaging satisfaction. Methods: A prospective cohort study was conducted with recruitment between 1 November 2021 and 30 June 2022. Participants completed the dry eye questionnaire (DEQ5), health-related quality-of-life (SF-8™), functional assessment of chronic illness therapy-treatment satisfaction-general (FACIT-TS-G), and general wellbeing surveys. Existing patients completed these once, and new patients were surveyed at baseline, 3 months post-treatment, and 6 months post-treatment. Results: Participants who completed all study requirements were 24 existing and 40 new Auto-SED and 10 existing and 8 new PT-SED patients. Auto-SED patients were younger [56.2 (±14.7) years] than PT-SED patients [71.4 (±10.0) years]. Participants used a mean of 1.8 (±1.1) SED, 5.3 (±2.9) times per day. In new patients, DEQ5 scores improved within 6 months from 14.0 (±2.9) to 10.6 (±3.4) for Auto-SED and from 12.9 (±3.7) to 11.4 (±2.8) for PT-SED. General wellbeing measures improved in the new Auto-SED from 7.0 (±1.9) to 7.8 (±1.7) but were reduced for new PT-SED from 6.7 (±2.9) to 6.1 (±2.9). Discussion: SED improved dry eye symptoms in most patients, regardless of the serum source. Patients using PT-SED showed decreases in some quality-of-life measures; however, recruitment was reduced due to operational constraints, and concurrent comorbidities were not assessed. General feedback for SED and vial packaging was positive, with some improvements identified.

Emerging Microfluidic Devices for Sample Preparation of Undiluted Whole Blood to Enable the Detection of Biomarkers.

Blood testing allows for diagnosis and monitoring of numerous conditions and illnesses; it forms an essential pillar of the health industry that continues to grow in market value. Due to the complex physical and biological nature of blood, samples must be carefully collected and prepared to obtain accurate and reliable analysis results with minimal background signal. Examples of common sample preparation steps include dilutions, plasma separation, cell lysis, and nucleic acid extraction and isolation, which are time-consuming and can introduce risks of sample cross-contamination or pathogen exposure to laboratory staff. Moreover, the reagents and equipment needed can be costly and difficult to obtain in point-of-care or resource-limited settings. Microfluidic devices can perform sample preparation steps in a simpler, faster, and more affordable manner. Devices can be carried to areas that are difficult to access or that do not have the resources necessary. Although many microfluidic devices have been developed in the last 5 years, few were designed for the use of undiluted whole blood as a starting point, which eliminates the need for blood dilution and minimizes blood sample preparation. This review will first provide a short summary on blood properties and blood samples typically used for analysis, before delving into innovative advances in microfluidic devices over the last 5 years that address the hurdles of blood sample preparation. The devices will be categorized by application and the type of blood sample used. The final section focuses on devices for the detection of intracellular nucleic acids, because these require more extensive sample preparation steps, and the challenges involved in adapting this technology and potential improvements are discussed.

Serological testing of blood donors to characterise the impact of COVID-19 in Melbourne, Australia, 2020.

Rapidly identifying and isolating people with acute SARS-CoV-2 infection has been a core strategy to contain COVID-19 in Australia, but a proportion of infections go undetected. We estimated SARS-CoV-2 specific antibody prevalence (seroprevalence) among blood donors in metropolitan Melbourne following a COVID-19 outbreak in the city between June and September 2020. The aim was to determine the extent of infection spread and whether seroprevalence varied demographically in proportion to reported cases of infection. The design involved stratified sampling of residual specimens from blood donors (aged 20-69 years) in three postcode groups defined by low (<3 cases/1,000 population), medium (3-7 cases/1,000 population) and high (>7 cases/1,000 population) COVID-19 incidence based on case notification data. All specimens were tested using the Wantai SARS-CoV-2 total antibody assay. Seroprevalence was estimated with adjustment for test sensitivity and specificity for the Melbourne metropolitan blood donor and residential populations, using multilevel regression and poststratification. Overall, 4,799 specimens were collected between 23 November and 17 December 2020. Seroprevalence for blood donors was 0.87% (90% credible interval: 0.25-1.49%). The highest estimates, of 1.13% (0.25-2.15%) and 1.11% (0.28-1.95%), respectively, were observed among donors living in the lowest socioeconomic areas (Quintiles 1 and 2) and lowest at 0.69% (0.14-1.39%) among donors living in the highest socioeconomic areas (Quintile 5). When extrapolated to the Melbourne residential population, overall seroprevalence was 0.90% (0.26-1.51%), with estimates by demography groups similar to those for the blood donors. The results suggest a lack of extensive community transmission and good COVID-19 case ascertainment based on routine testing during Victoria's second epidemic wave. Residual blood donor samples provide a practical epidemiological tool for estimating seroprevalence and information on population patterns of infection, against which the effectiveness of ongoing responses to the pandemic can be assessed.