Increasing the upper age limit for blood donation: Perspectives from older donors.

BACKGROUND AND OBJECTIVES: In the Netherlands, as of April 2018, the upper age limit for blood donation has been raised from 69 to 79 years, providing an opportunity to study older donors' perspectives regarding donating at older age. This study aims to explore whether older donors agree with the increase of the age limit, if they feel obliged to continue donating, to identify their motivators and barriers for donating blood and describe donation-related experiences and complications. MATERIALS AND METHODS: An online survey was distributed among Dutch blood donors aged 68-73 years. The survey contained questions regarding the increase of the upper age limit, motivations and barriers for donating, donation-related experiences and obligatory feelings to continue donating. RESULTS: Six hundred sixty donors (55%) were included in the analyses, including 38 stopped donors. Most donors (92%) agreed with the increase of the upper age limit. Approximately 63% of participating donors felt obliged to continue donating, especially women with high education. Donors indicated they felt healthy enough to keep donating (95%), and 72% thought it is good for their health to keep donating. Few donors reported that they found it hard to keep donating (5%) or indicated that they did not feel healthy enough to donate or thought it was not safe for them anymore (3.4%). CONCLUSION: Most of the older donors agree with the increase of the upper age limit for blood donation, report only few and minor donation-related experiences or complications and are highly motivated to continue their donor career at an older age.

The Prognostic Role of Global Longitudinal Strain and NT-proBNP in Heart Failure Patients Receiving Cardiac Resynchronization Therapy.

BACKGROUND: We aimed to evaluate whether baseline GLS (global longitudinal strain), NT-proBNP, and changes in these after cardiac resynchronization therapy (CRT) can predict long-term clinical outcomes and the echocardiographic-based response to CRT (defined by 15% relative reduction in left ventricular end-systolic volume). METHODS: We enrolled 143 patients with stable ischemic heart failure (HF) undergoing CRT-D implantation. NT-proBNP and echocardiography were obtained before and 6 months after. The patients were followed up (median: 58 months) for HF-related deaths and/or HF hospitalizations (primary endpoint) or HF-related deaths (secondary endpoint). RESULTS: A total of 84 patients achieved the primary and 53 the secondary endpoint, while 104 patients were considered CRT responders and 39 non-responders. At baseline, event-free patients had higher absolute GLS values (p < 0.001) and lower NT-proBNP serum levels (p < 0001) than those achieving the primary endpoint. A similar pattern was observed in favor of CRT responders vs. non-responders. On Cox regression analysis, baseline absolute GLS value (HR = 0.77; 95% CI, 0.51-1.91; p = 0.002) was beneficially associated with lower primary endpoint incidence, while baseline NT-proBNP levels (HR = 1.55; 95% CI, 1.43-2.01; p = 0.002) and diabetes presence (HR = 1.27; 95% CI, 1.12-1.98; p = 0.003) were related to higher primary endpoint incidence. CONCLUSIONS: In HF patients undergoing CRT-D, baseline GLS and NT-proBNP concentrations may serve as prognostic factors, while they may predict the echocardiographic-based response to CRT.

Functional host-specific adaptation of the intestinal microbiome in hominids.

Fine-scale knowledge of the changes in composition and function of the human gut microbiome compared that of our closest relatives is critical for understanding the evolutionary processes underlying its developmental trajectory. To infer taxonomic and functional changes in the gut microbiome across hominids at different timescales, we perform high-resolution metagenomic-based analyzes of the fecal microbiome from over two hundred samples including diverse human populations, as well as wild-living chimpanzees, bonobos, and gorillas. We find human-associated taxa depleted within non-human apes and patterns of host-specific gut microbiota, suggesting the widespread acquisition of novel microbial clades along the evolutionary divergence of hosts. In contrast, we reveal multiple lines of evidence for a pervasive loss of diversity in human populations in correlation with a high Human Development Index, including evolutionarily conserved clades. Similarly, patterns of co-phylogeny between microbes and hosts are found to be disrupted in humans. Together with identifying individual microbial taxa and functional adaptations that correlate to host phylogeny, these findings offer insights into specific candidates playing a role in the diverging trajectories of the gut microbiome of hominids. We find that repeated horizontal gene transfer and gene loss, as well as the adaptation to transient microaerobic conditions appear to have played a role in the evolution of the human gut microbiome.

[Treatment regimen for deep sternal wound infections after cardiac surgical interventions in an interdisciplinary approach]. / Behandlungsregime tiefer sternaler Wundinfektionen nach kardiochirurgischen Eingriffen im interdisziplinären Ansatz.

The aim of this article is to present the importance of a structured and situation-adapted approach based on the diagnostic and therapeutic strategy in the interdisciplinary treatment of 54 patients with deep sternal wound infections (DSWI) after cardiac surgical interventions and the results achieved. The patients were 41 men and 13 women with an average age of 65.1 years, who developed a DSWI after a cardiac surgical intervention during the period 2003-2016. The treatment strategy included a thorough debridement including the removal of indwelling foreign material, the reconstruction with a stable re-osteosynthesis after overcoming the infection and if necessary, situation-related surgical flaps for a defect coverage with a good blood supply and mandatory avoidance of dead spaces. A total of 146 operations were necessary (average 2.7 operations/patient, range 1-7 operations). In 24.1 % of the cases a one-stage approach could be carried out. In 41 patients negative pressure wound therapy (NPWT) with programmed sponge changing was used for wound conditioning (mean 5 changes, standard deviation, SD±â€¯5.6 changes over 22 days, SD±â€¯23.9 days, change interval every 3-4 days in 40.7% of the cases). In 33 patients a bilateral myocutaneous pectoralis major flap was used, in 4 patients a vertical rectus abdominis myocutaneous (VRAM) flap and in 7 patients both were carried out. A total of 43 osteosynthesis procedures were carried out on the sternum with fixed-angle titanium plates. Of the patients 7 died during intensive care unit treatment (total mortality 13 %, n = 5, 9.3 % ≤ 30 days) or in the later course. Of the patients 47 (87.1 %) could be discharged with a cleansed infection. In 2 patients the implant was removed after 2 years due to loosening.

[Calcaneoplasty with radiofrequency cementing following balloon reduction]. / Kalkaneoplastie mit Radiofrequenzzementierung nach Ballonaufrichtung.

The standard surgical procedure for complex calcaneal fractures is open reduction, internal reduction and internal stable angle plate osteosynthesis via a lateral approach. More recently, options for minimally invasive and percutaneous surgical strategies have been presented [4, 7]. As a possible procedural alternative for a covered, surgical treatment of calcaneal fractures, calcaneoplasty is discussed and applied in this context [5]. In this case series of five complex calcaneal fractures presented here, a balloon catheter was used for percutaneous reduction to restore the alignment of the calcaneus.This was followed by placement of PMMA cement in radiofrequency application and osteosynthesis using percutaneous cannulated screws. This Vicenti technique allows stable reduction and retention with early partial weight bearing with an overall low complication rate [17].

Iron supplementation: A qualitative study on the perception of blood donors, blood collection staff and donor physicians.

BACKGROUND AND OBJECTIVES: Iron supplementation is an effective strategy to mitigate donation-induced iron deficiency in blood donors. However, evidence on the perception of individuals involved in blood donation on iron supplementation as a blood service policy is lacking. This study aimed to evaluate the knowledge and perception of whole blood donors (donors), blood collection staff (collection staff) and donor physicians (physicians) regarding donation-induced iron loss and iron supplementation. MATERIALS AND METHODS: Online focus group discussions had four to six participants and followed a structured questioning approach. All participants had to be fluent in Dutch to participate, and donors had donated at least five times. Sixteen donors, eight collection staff members and four physicians participated in this study. Recordings were transcribed, coded and analysed using a grounded theory approach. RESULTS: Awareness of donation-induced iron loss was limited in donors. Donors and physicians were predominantly positive towards iron supplementation; the primary motivator for donors was to prevent deferral and reduce iron-deficiency-related symptoms. Improving donor health was the main argument for physicians to advocate iron supplementation. Staff had a critical view on iron supplementation as a policy, as they perceived it as unethical and possibly ineffective. A knowledge gap might underlie their concerns. CONCLUSION: Most individuals involved in blood donation are positive towards iron supplementation as a blood service policy. If implemented, guidance and monitoring is desired and adequate education of all stakeholders is required.

Understanding the mechanism by which Gd(III) coiled coils achieve magnetic resonance relaxivity - a study into the water coordination chemistry.

A class of Gd(III) coiled coils achieve high MRI relaxivity, in part due to their slow rotational correlation time. However, extending their length is unable to further enhance performance, as the mechanism by which relaxivity is achieved is dominated by the presence of three inner sphere waters in rapid exchange, through an associative mechanism.

Impact of Time of Surgery on the Outcome after Surgical Stabilization of Rib Fractures in Severely Injured Patients with Severe Chest Trauma-A Matched-Pairs Analysis of the German Trauma Registry.

Purpose: In severely injured patients with multiple rib fractures, the beneficial effect of surgical stabilization is still unknown. The existing literature shows divergent results, and the indication and especially the right timing of an operation are the subject of a broad discussion. The aim of this study was to determine the influence of the time point of surgical stabilization of rib fractures (SSRF) on the outcome in a multicenter database with special regard to the duration of ventilation, intensive care, and overall hospital stay. Methods: Data from the TraumaRegister DGU collected between 2010 and 2019 were used to evaluate patients above 16 years of age with severe rib fractures [Abbreviated Injury Score (AIS) ≥ 3] who received an SSRF in a matched-pairs analysis. In this matched-pairs analysis, we compared the effects of an early SSRF within 48 h after initial trauma vs. late SSRF 3-10 days after trauma. Results: After the selection process, we were able to find 142 matched pairs for further evaluation. Early SSRF was associated with a significantly shorter length of stay in the intensive care unit (16.2 days vs. 12.7 days, p = 0.020), and the overall hospital stay (28.5 days vs. 23.4 days, p = 0.005) was significantly longer in the group with late SSRF. Concerning the days on mechanical ventilation, we were able to demonstrate a trend for an approximately 1.5 day shorter ventilation time for patients after early SSRF, although this difference was not statistically significant (p = 0.226). Conclusions: We were able to determine the significant beneficial effects of early SSRF resulting in a shorter intensive care unit stay and a shorter length of stay in hospital and additionally a trend to a shorter time on mechanical ventilation.

Cardiovascular Benefits for Blood Donors? A Systematic Review.

It has been proposed that blood donation could be protective against cardiovascular disease. The aim of this study is to systematically summarize and evaluate existing observational and experimental studies on effects of blood donation on cardiovascular risk and disease in donor and general populations. The electronic databases PubMed and EMBASE were searched until March 2019 for experimental and observational studies on blood donation and cardiovascular risk or disease. Excluded were studies performed in patient populations or with controls compared to a patient population, and studies performed in individuals aged <18 or >70. All identified studies were independently screened for eligibility and quality using validated scoring systems by 2 reviewers. A total of 44 studies met all criteria. We included 41 observational studies and 3 experimental studies. 14 studies had a quality assessment score of 7 or higher. Of those, a majority of 9 studies reported a protective effect of blood donation, while 5 studies found no effects on cardiovascular risk factors. Results on other various outcomes were inconsistent and study quality was generally poor. Whether or not blood donation protects against cardiovascular disease remains unclear. Studies showing beneficial effects may have inadequately dealt with the healthy donor effect. High quality studies are lacking and therefore definite conclusions cannot be drawn. Large RCTs or cohort studies of high quality with sufficient follow-up should be conducted to provide evidence on the possible association between blood donation and cardiovascular disease.

Ferritin-guided iron supplementation in whole blood donors: optimal dosage, donor response, return and efficacy (FORTE)-a randomised controlled trial protocol.

BACKGROUND: Frequent whole blood donors have an increased risk of developing iron deficiency. Iron deficiency can have detrimental health effects when left untreated. Donation intervals are commonly too short to replenish iron stores and extending these reduces donor availability. Oral iron supplementation is known to shorten iron store recovery time but may also induce gastrointestinal complaints. We aim to optimise the effectiveness of iron supplements while minimising the risks of side effects. Therefore, we will evaluate the impact of different iron supplementation protocols in terms of dosage and frequency on ferritin and haemoglobin levels, gastrointestinal side effects, iron deficiency-related symptoms and donor return compared with placebo supplementation. METHODS: Twelve hundred whole blood donors with ferritin levels ≤30 µg/L are included into a double-blind, randomised controlled trial. Participants are randomly allocated to one of six arms, administering capsules containing 0 mg, 30 mg or 60 mg of iron, either on alternate days or daily for 56 days. At baseline and 56, 122 and 182 days of follow-up, ferritin and haemoglobin levels are measured, and compliance, donor return, dietary iron intake, gastrointestinal, iron deficiency-related symptoms and general health are assessed by questionnaire. ETHICS AND DISSEMINATION: This study will provide a comprehensive overview of the effects of different frequencies and dosages of administration of iron supplements on iron status and health effects, thereby considering individual differences in treatment adherence and lifestyle. The outcome will provide scientific evidence to guide the debate if and how oral iron supplements may support the recovery of whole blood donors with low ferritin levels. TRIAL REGISTRATION NUMBER: NL8590; The Dutch trial registry.

Long-term water quality assessments under changing land use in a large semi-arid catchment in South Africa.

Increasing nutrient loads from land use and land cover (LULC) change degrade water quality through eutrophication of aquatic ecosystems globally. The Vaal River Catchment in South Africa is an agriculturally and economically important area where eutrophication has been a problem for decades. Effective mitigation strategies of eutrophication in this region require an understanding of the relationship between LULC change and water quality. This study assessed the long-term impacts of LULC changes on nitrate (NO3-N) and orthophosphate (PO4-P) pollution in the lower Vaal River Catchment between 1980 and 2018. Multi-year LULC was mapped from Landsat imagery and changes were determined. Long-term trends in NO3-N and PO4-P loads and concentrations in river water samples were analysed, while multi-year LULC data were ingested into the Soil and Water Assessment Tool (SWAT) to simulate the impacts of LULC changes in NO3-N and PO4-P loads. Main LULC changes included an increase in the irrigated area by 262% and in built-up area by 33%. This occurred at the expense of cultivated dryland fields and rangelands. In situ data analysis showed that at the catchment inlet, PO4-P concentration and loads significantly increased, while NO3-N concentration and loads decreased between 1980 and 2018. At the catchment outlet, only PO4-P loads increased, while NO3-N loads and concentrations remained the same. SWAT simulations at the Hydrologic Response Unit scale showed that irrigated land was the largest contributor to NO3-N leaching per ha. Aggregation of nutrient loads by LULC type showed increased nutrient loads from irrigated and built-up areas over time, while loads from dryland areas decreased. At catchment scale, dryland remained an important contributor of the annual nutrient loads total because of its large area. In future, research efforts should focus on crop management practices to reduce nutrient loads.

Blood group AB increases risk for surgical necrotizing enterocolitis and focal intestinal perforation in preterm infants with very low birth weight.

Necrotizing enterocolitis (NEC) and focal intestinal perforation (FIP) are two of the most common emergencies of the gastrointestinal tract in preterm infants with very low birth weight (VLBW, birth weight < 1500 g). Identification of risk factors among these children is crucial for earlier diagnosis and prompt intervention. In this study, we investigated a relationship between ABO blood groups and the risk for surgical NEC/FIP. We genotyped the ABO locus (rs8176746 and rs8176719) in VLBW infants enrolled in a prospective, population-based cohort study of the German Neonatal Network (GNN). Of the 10,257 VLBW infants, 441 (4.3%) had surgical NEC/FIP. In univariate analyses, the blood group AB was more prevalent in VLBW infants with surgical NEC/FIP compared to non-AB blood groups (OR 1.51, 95% CI 1.07-2.13, p = 0.017; absolute risk difference 2.01%, 95% CI 0.06-3.96%). The association between blood group AB and surgical NEC/FIP was observed in a multivariable logistic regression model (OR of 1.58, 95% CI 1.10-2.26, p = 0.013) as well. In summary, our study suggests that the risk of surgical NEC and FIP is higher in patients with blood group AB and lower in those having non-AB blood groups.

Penetrating injuries in Germany - epidemiology, management and outcome an analysis based on the TraumaRegister DGU®.

BACKGROUND: The management of penetrating wounds is a rare challenge for trauma surgeons in Germany and Central Europe as a result of the low incidence of this type of trauma. In Germany, penetrating injuries are reported to occur in 4-5 % of the severely injured patients who are enrolled in the TraumaRegister DGU® (trauma registry of the German Trauma Society). They include gunshot injuries, knife stab injuries, which are far more common, and penetrating injuries of other origin, for example trauma caused by accidents. The objective of this study was to assess the epidemiology and outcome of penetrating injuries in Germany, with a particular focus on the level of care provided by the treating trauma centre to gain more understanding of this trauma mechanism and to anticipate the necessary steps in the initial treatment. MATERIALS AND METHODS: Since 2009, the TraumaRegister DGU® has been used to assess not only whether a trauma was penetrating but also whether it was caused by gunshot or stabbing. Data were taken from the standard documentation forms that participating German hospitals completed between 2009 and 2018. Excluded were patients with a maximum abbreviated injury scale (MAIS) score of 1 with a view to obtaining a realistic idea of this injury entity, which is rare in Germany. RESULTS: From 2009 to 2018, there were 1123 patients with gunshot wounds, corresponding to a prevalence rate of 0.5 %, and 4333 patients with stab wounds (1.8 %), which were frequently caused by violent crime. The high proportion of intentionally self-inflicted gunshot wounds to the head resulted in a cumulative mortality rate of 41 % for gunshot injuries. Stab wounds were associated with a lower mortality rate (6.8 %). Every fourth to fifth patient with a gunshot or stab wound presented with haemorrhagic shock, which is a problem that is seen during both the prehospital and the inhospital phase of patient management. Of the patients with penetrating injuries, 18.3 % required transfusions. This percentage was more than two times higher than that of the basic group of patients of the TraumaRegister DGU®, which consists of patients with a MAIS ≥ 3 and patients with a MAIS of 2 who died or were treated on the intensive care unit. CONCLUSIONS: In Germany, gunshot and stab wounds have a low incidence and are mostly caused by violent crime or attempted suicides. Depending on the site of injury, they have a high mortality and are often associated with major haemorrhage. As a result of the low incidence of these types of trauma, further data and analyses are required in order to provide the basis for evaluating the long-term quality of the management of patients with stab or gunshot wounds.

Low awareness of past SARS-CoV-2 infection in healthy plasma donors.

Awareness of infection with SARS-CoV-2 is crucial for the effectiveness of COVID-19 control measures. Here, we investigate awareness of infection and symptoms in relation to antibodies against SARS-CoV-2 in healthy plasma donors. We asked individuals donating plasma across the Netherlands between May 11th and 18th 2020 to report COVID-19-related symptoms, and we tested for antibodies indicative of a past infection with SARS-CoV-2. Among 3,676 with antibodies, and from questionnaire data, 239 (6.5%) are positive for SARS-CoV-2 antibodies. Of those, 48% suspect no COVID-19, despite the majority reporting symptoms; 11% of seropositive individuals report no symptoms and 27% very mild symptoms at any time during the first peak of the epidemic. Anosmia/ageusia and fever are most strongly associated with seropositivity. Almost half of seropositive individuals do not suspect SARS-CoV-2 infection. Improved recognition of COVID-19 symptoms, in particular, anosmia/ageusia and fever, is needed to reduce widespread SARS-CoV-2 transmission.

Host traits, lifestyle and environment are associated with human skin bacteria.

BACKGROUND: The human skin offers diverse ecosystems for microbial symbionts. However, the factors shaping skin-microbiome interactions are still insufficiently characterized. This contrasts with the broader knowledge about factors influencing gut microbiota. OBJECTIVES: We aimed to investigate major patterns of association of host traits, lifestyle and environmental factors with skin bacteria in two German populations. METHODS: This is a cross-sectional study with 647 participants from two population-based German cohorts, PopGen (n = 294) and KORA FF4 (n = 353), totalling 1794 skin samples. The V1-V2 regions of the 16S ribosomal RNA (rRNA) gene were sequenced. Associations were tested with two bacterial levels, community (beta diversity) and 16S rRNA gene amplicon sequence variants (ASVs). RESULTS: We validated known associations of the skin microbiota with skin microenvironment, age, body mass index and sex. These factors were associated with beta diversity and abundance of ASVs in PopGen, which was largely replicated in KORA FF4. Most intriguingly, dietary macronutrients and total dietary energy were associated with several ASVs. ASVs were also associated with smoking, alcohol consumption, skin pH, skin type, transepidermal water loss, education and several environmental exposures, including hours spent outdoors. Associated ASVs included members of the genera Propionibacterium, Corynebacterium and Staphylococcus. CONCLUSIONS: We expand the current understanding of factors associated with the skin bacterial community. We show the association of diet with skin bacteria. Finally, we hypothesize that the skin microenvironment and host physiology would shape the skin bacterial community to a greater extent compared with a single skin physiological feature, lifestyle and environmental exposure.

New blood donors in times of crisis: Increased donation willingness, particularly among people at high risk for attracting SARS-CoV-2.

BACKGROUND: Traditionally, during crises the number of new blood donors increases. However, the current coronavirus disease 2019 (COVID-19) pandemic created additional barriers to donate due to governmental prevention measures and increased personal health risks. In this report, we examined how the pandemic affected new donor registrations in the Netherlands, especially among groups with higher risk profiles for severe COVID-19. Additionally, we explored the role of media for blood donation and new donor registrations. STUDY DESIGN AND METHODS: We analyzed new donor registrations and attention for blood donation in newspapers and on social media from January until May 2020, in comparison to the same period in 2017 to 2019. RESULTS: After the introduction of nationwide prevention measures, several peaks in new donor registrations occurred, which coincided with peaks in media attention. Interestingly, people with a higher risk profile for COVID-19 (e.g., due to age or region of residence) were overrepresented among new registrants. DISCUSSION: In sum, the first peak of the current pandemic has led to increased new blood donor registrations, despite the associated increased health risks. Time and future studies will have to tell whether these new donors are one-off 'pandemic' donors or if they will become regular, loyal donors.

Generation of two iPSC clones (MHHi021-A and MHHi021-B) from a patient with hypertrophic cardiomyopathy with p.Arg723Gly mutation in the MYH7 gene.

Hypertrophic cardiomyopathy (HCM) is the most common form of genetic heart disease and is characterized by abnormal thickening of the left ventricular wall and interventricular septum. Here we describe the generation of two induced pluripotent stem cell (iPSC) clones from a HCM patient, heterozygous for the p.Arg723Gly (c.2169C > G) mutation in the MYH7 gene. The generated iPSC clones may provide a useful resource for disease modelling to study the mechanisms underlying HCM pathogenesis in iPSC derived progenies, in particular cardiomyocytes.

Whole blood donors' post-donation symptoms diminish quickly but are discouraging: Results from 6-day symptom diaries.

BACKGROUND: Whole blood donors may experience post-donation symptoms such as fatigue, dizziness, or headache after blood donation, which could influence donor retention. We aimed to examine post-donation symptoms during 1 week after whole blood donation, investigate donor characteristics associated with symptoms, and evaluate associations between symptoms and donor return. METHODS: During 1 week, whole blood donors who donated successfully at one of the collection centers in The Netherlands were invited to participate. Three thousand seventy six donors filled in a diary, assessing post-donation symptoms during days 1 to 6 after donation. We used linear mixed models analyses to determine the change in post-donation symptoms after donation for male and female donors separately. Furthermore, we investigated associations between post-donation symptoms and donors' physical characteristics using multivariable regression and determined associations between symptoms and donor return. RESULTS: Donors reported fatigue as the most common symptom, with approximately 3% of donors experiencing severe problems at the first day after donation. Multiple symptoms improved significantly up to day 3 after whole blood donation. Age, BMI, blood pressure (male donors), and blood volume (female donors) were significantly associated with post-donation symptoms. Donors with less fatigue after whole blood donation were more likely to return for their next donation within 31 days after receiving an invitation. CONCLUSION: Post-symptoms improve up to 3 days after whole blood donation. Our results may help blood collection centers to identify donors more prone to post-donation symptoms and provide personalized information about the presence and course of post-donation symptoms, possibly increasing donor return rates.

Ferritin measurement IN Donors-Effectiveness of iron Monitoring to diminish iron deficiency and low haemoglobin in whole blood donors (FIND'EM): study protocol for a stepped wedge cluster randomised trial.

BACKGROUND: Blood donors are at risk for reduced iron stores, because of which donor iron monitoring received increased attention in the last decade. Despite the importance for donor health, international consensus on an appropriate policy for iron monitoring is lacking. Therefore, we conduct a trial to evaluate to what extent ferritin-guided donation intervals are effective in increasing haemoglobin and ferritin levels, decreasing low-haemoglobin deferral, increasing donor return and improving the health of whole blood donors in the Netherlands. METHODS: Sanquin Blood Bank is implementing ferritin-guided donation intervals to prevent donors from increasing iron loss at repeated donations. Using a stepped wedge cluster randomised trial approach, the design involves a random crossover of 29 clusters of blood collection centres from the existing policy without ferritin measurements to a ferritin-guided donation interval policy. This new policy includes ferritin measurements for all new donors and at every 5th whole blood donation, extending donation intervals to 6 months if ferritin is 15-≤ 30 ng/mL and to 12 months if ferritin is < 15 ng/mL. We measure ferritin levels of whole blood donors from stored plasma samples and collect haemoglobin levels and information on low-haemoglobin deferral and donor return from the donor database before, during and after the implementation period. We measure donor health during and after the implementation period using questionnaires, assessing physical and mental wellbeing and iron deficiency- and donation-related symptoms. We use multilevel analyses to investigate differences in ferritin and haemoglobin levels, low-haemoglobin deferral rates, donor return and donor health from whole blood donors, between blood collection centres that have versus those that have not yet implemented the ferritin-guided donation interval policy. DISCUSSION: This stepped wedge cluster randomised trial will provide insight into the effectiveness of ferritin-guided donation intervals in lowering iron deficiency, decreasing donor deferrals due to low haemoglobin and improving donor health. We will evaluate a policy that is implemented nationwide in a real-life setting. Our study is therefore not limited to a small experimental setting and the results will guide policymakers seeking an appropriate policy for iron monitoring. TRIAL REGISTRATION: The Dutch trial registry NTR6738 . Registered on 29 September 2017. Retrospectively registered.

Low awareness of past SARS-CoV-2 infection in healthy adults

BackgroundThe coronavirus disease 2019 (COVID-19) pandemic challenges governments worldwide to balance appropriate virus control measures and their societal and economic consequences. These control measures include the identification, isolation and testing of potentially infected individuals. As this relies on an individuals awareness of infection, we investigated the extent to which healthy adults suspected having had COVID-19, and how COVID-19 suspicion and symptoms relate to antibodies indicative of a past infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Methods and findingsFor this cross-sectional study, individuals donating plasma anywhere in the Netherlands between May 11th and 18th were screened for total SARS-CoV-2 antibodies using ELISA and invited to participate in an online questionnaire about COVID-19-related symptoms and awareness. Antibody and questionnaire data were complete for 3,676 individuals, including 239 (6.5%) that tested positive for SARS-CoV-2 antibodies. Here, we show that a 38% of the individuals that tested positive for SARS-CoV-2 antibodies reported having had no or only very mild symptoms at any time during the peak of the epidemic. The loss of taste and/or smell in particular was significantly associated with seropositivity, independent of age and sex. Forty-eight percent of antibody-positive persons did not suspect having had COVID-19, in spite of most of them reporting symptoms. ConclusionsAwareness of infection was low among individuals that tested positive for SARS-CoV-2 antibodies, even at the peak of the epidemic. Improved awareness and recognition of COVID-19 symptoms and tracing of asymptomatic contacts is crucial to halting SARS-CoV-2 transmission.