Anti-SARS-CoV-2 total immunoglobulin and neutralising antibody responses in healthy blood donors throughout the COVID-19 pandemic: a longitudinal observational study.

INTRODUCTION: Quantifying antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and neutralising antibodies may help to understand protection at the individual and population levels. Determination of neutralising antibodies using classical virus neutralisation tests (VNT) is considered the gold standard, but they are costly and time-intensive. Enzyme-linked immunosorbent assay (ELISA)-based surrogate VNTs (sVNT) or anti-SARS-CoV-2 spike protein receptor binding domain immunoglobulins (anti-S-RBD Ig) may be suitable alternatives to VNTs. We aimed to (a) explore the correlations between anti-S-RBD Ig, VNT, and sVNT measurements and (b) describe humoral immunity against SARS-CoV-2 after vaccination, natural infection, and vaccine breakthrough infection in healthy blood donors. METHODS: We measured total anti-SARS-CoV-2 Ig in 5714 serum samples from 2748 healthy individuals visiting the Swiss Red Cross Blood Donation Centre in Basel from 03/2020 to 04/2022. We used the Elecsys® Anti-SARS-CoV-2 immunoassay (Roche) against the N- and S-receptor binding domain (RBD) proteins. In a subset of 548 samples from 123 donors, we conducted sVNTs against the Wuhan wild-type SARS-CoV-2 (SARS-CoV-2 Neutralizing Antibodies Detection Kit; Adipogen™). In 100 samples from 40 donors, we correlated sVNT and VNTs against the wild-type (D614G WU1) virus. Surveys were sent to the blood donors to collect data on their SARS-CoV-2 infection and vaccination status. Using this data, donors were categorised as "vaccination only", "infection before vaccination", "post-vaccine breakthrough infection", and "natural infection only". RESULTS: Our longitudinal observation study cohort consisted of 50.7% males with a median age of 31 years (range 18-75 y). Anti-SARS-CoV-2 N protein positivity rates per month indicate 57.1% (88/154) of the cohort was infected up to 04/2022. No differences in seropositivity were found between sexes, age groups, blood types (AB0 or RhD), and cytomegalovirus serostatus. We observed a high correlation between anti-S-RBD Ig and inhibition percentage (Spearman's ρ = 0.92, Kendall's τ = 0.77, p <0.0001). We determined the sensitivity and specificity for the manufacturers' thresholds for detecting virus-neutralising effects and computed the "best" cut-off based on our real-world data. We categorised 722/1138 (63.5%) donors as vaccination only (82.3%), post-vaccine breakthrough infection (7.8%), infection before vaccination (5.8%), and natural infection only (4.2%). We observed a lower inhibition percentage in the natural infection-only group than in all other vaccinated groups. The infection before vaccination group had higher anti-S-RBD Ig titres after the first vaccine dose than the other vaccinated groups. CONCLUSION: In total, 57.1% of healthy blood donors were infected with SARS-CoV-2, but natural infection without evidence of vaccination seems to result in substantially lower neutralising antibody levels. An estimate of antibody neutralisation may be helpful to assess reinfection risk. Total anti-S-RBD Ig correlates with surrogate virus neutralisation test results, a surrogate for neutralisation; therefore, we suggest that total anti-S-RBD Ig may estimate the level of neutralising antibodies. The threshold for protection from an unfavourable clinical outcome must be evaluated in prospective clinical cohorts.

Causes of pre and post-donation deferrals among blood donors, at Kwale Satellite Blood Transfusion Center, Kwale County, Kenya, 2018-2022.

BACKGROUND: Both pre-donation and post-donation deferrals pose challenges to blood safety and availability. This study delved into the deferral rates before donations and their underlying reasons, as, transfusion transmissible infections (TTIs) leading to post-donation deferrals among potential blood donors at the Kwale Satellite Blood Transfusion Centre (KSBTC) in Kenya. METHODS: We performed a retrospective electronic record review of pre- and post-donation deferrals among blood donors at KSBTC, 2018-2022. The pre-donations deferral rate and reasons for deferral were analyzed. Accepted donations were analyzed to determine the prevalence of HIV, hepatitis B (HBV), hepatitis C (HCV), and syphilis. Descriptive statistics were calculated and both crude odds ratio (COR) and adjusted odds ratio (AOR), and their 95% confidence intervals (CI) were calculated. Variables with p < 0.05 were considered statistically significant. RESULTS: A review was conducted on 12,633 blood donation records. Among these, individuals 2,729/12,633 (21.60%) were deferred from donating with the primary reason being low hemoglobin levels, constituting 51.86% of deferrals. Around 773/9,904 (7.80%) of blood units, were discarded due to at least one TTI. Among these, HBV accounted for 4.73%, HIV for 2.01%, HCV for 1.21%, and Syphilis for 0.59% of cases. The adjusted odds ratio for male donors were, (aOR = 1.3, 95% CI 1.01-1.57), donors with none or primary education level (aOR = 1.4 95% CI 1.11-1.68), first-timer donors (aOR = 1.2, 95% CI 1.01-1.44), and static strategy for blood collection (aOR = 1.4, 95%CI 1.12-1.63) were independently potentially associated with testing positive for at least one TTI. CONCLUSION: The study indicates that TTIs continue to pose a risk to the safety of Kenya's bloodstock, with a notable prevalence of HBV infections. Male donors, individuals with limited education, first-time donors, and utilizing a fixed strategy for blood collection were identified as potential risk factors independently associated with TTIs.

Syphilis testing in blood donors, France, 2007 to 2022.

BackgroundSyphilis in blood donors (BD) has increased in many countries.AimWe aimed to describe trends in syphilis seroposivity in BD in France, to identify risk factors and assess if a non-treponemic test (NTT) could define BD having recovered from syphilis for more than 1 year.MethodsThe analysis covered the period 2007 to 2022 and 45,875,939 donations. Of the 474 BD syphilis-positive in 2022, 429 underwent additional investigations with an NTT. History of syphilis was obtained at the post-donation interview or based on serology results for repeat donors.ResultsUntil 2021, positivity rates remained stable (mean: 1.18/10,000 donations, range: 1.01-1.38). An increased rate was observed in 2022 (1.74/10,000; p = 0.02). Over the whole study period, prevalence was 2.2 times higher in male than in female BD (4.1 times higher in 2022). The proportion of males with an identified risk factor who have sex with men increased from 16.7% in 2007 to 64.9% in 2022. Based on NTT, 79 (18%) of the donors who were seropositive in 2022 were classified as having been infected in the previous year. History of syphilis was available for 30 of them. All had an infection within the previous 3 years. Among seven donors with a syphilis < 12 months before testing, one had an NTT titre ≥ 8, three a titre between 1 and 4, three were negative.ConclusionSyphilis seropositivity increased considerably in BDs in 2022, mostly in males, notably MSM. Available data did not allow appropriate evaluation of the NTT to distinguish recent from past infection.

Self-reported high-risk behavior among first-time and repeat replacement blood donors; a four-year retrospective study of patterns.

BACKGROUND: There is no replacement for blood, and patients requiring transfusion depend on human donors, most of whom are family donors. Family donors may deny engagement in high-risk activities, which threaten the safety of donated blood. This study determined frequency of self-reported high-risk behaviors among replacement donors. METHODS: This retrospective study recruited 1317 donor records from 2017-2020, at Mankranso Hospital, Ghana. Data from archived donor questionnaires were extracted and analyzed with SPSS and GraphPad. Frequencies, associations, and quartiles were presented. RESULTS: The donors were predominantly males (84.4%), 17-26 years old (43.7%), informal workers (71.8%), rural inhabitants (56.5%), first-time (65.0%), and screened in the rainy season (56.3%). Donation frequency was significantly associated with age, sex, occupation, and residence. Repeat donors were significantly older (p≤0.001). More males than females were deferred (p = 0.008), drug addicts (p = 0.001), had body modifications (p = 0.025), multiple sexual partners (p = 0.045), and STIs (p≤0.001), whereas, more females were recently treated (p = 0.044). Weight loss (p = 0.005) and pregnancy (p = 0.026) were frequent among 17-26-year group, whereas, tuberculosis was frequent among 37-60-year group (p = 0.009). More first-time donors were unwell (p = 0.005), deferred (p≤0.001), pregnant (p = 0.002), drug addicts, had impending rigorous activity (p = 0.037), body modifications (p = 0.001), multiple sexual partners (p = 0.030), and STIs (p = 0.008). STIs were frequent in the dry season (p = 0.010). First-time donors had reduced hemoglobin (p = 0.0032), weight (p = 0.0003), and diastolic pressure (p = 0.0241). CONCLUSION: Donation frequency was associated with age, sex, occupation, and residence, with first-time donors younger than repeat donors. Deferral from donation, drug addiction, body modification, multiple sexual partners, and STIs were frequent among males, whereas, more females received treatment. Tuberculosis was frequently reported among older adults, whereas, weight loss and pregnancy were frequent among younger individuals. More first-time donors reported being unwell, deferred, drug addiction, body modifications, multiple sexual partners, STIs, and pregnant. Hemoglobin, weight, and diastolic BP were reduced among first-time donors.

Sociodemographic influences on private and professional contact behaviour during the COVID-19 pandemic in Germany: cross-sectional analysis based on a Regional Blood Donor Cohort.

OBJECTIVE: The COVID-19 pandemic has had significant health and socioeconomic impacts worldwide. Extensive measures, including contact restrictions, were implemented to control the spread of the virus. This study aims to examine the factors that influenced private and professional contact behaviour during the COVID-19 pandemic. RESULTS: We used baseline data (January-April 2021) from the SeMaCo study (Serologische Untersuchungen bei Blutspendern des Großraums Magdeburg auf Antikörper gegen SARS-CoV-2), a longitudinal, regional cohort study assessing COVID-19 seroprevalence in blood donors from Magdeburg and surrounding areas in Germany. In the blood donor cohort (n = 2,195), there was a general reduction in private contacts (by 78.9%) and professional contacts (by 54.4%) after March 18, 2020. Individuals with higher education reduced both private (by 84.1%) and professional (by 70.1%) contacts more than those with lower education levels (private contacts 59.5%; professional contacts 37%). Younger age groups (18-30 years) reduced private contacts more frequently (by 85.4%) than older individuals (61-83 years, by 68.6%) and demonstrated a higher likelihood of private contact reduction compared to older age groups (51-60 years: odds ratio (OR) 0.45 [95% [CI] 0.32-0.65]; 61-83 years: OR 0.33 [95% [CI] 0.22-0.48]).

Hepatitis E Virus in the United States and Canada: Is It Time to Consider Blood Donation Screening?

Hepatitis E virus (HEV) is the most common cause of acute viral hepatitis in the world and can lead to severe complications in immunocompromised individuals. HEV is primarily transmitted through eating pork, which has led to an increased in anti-HEV IgG seropositivity in the general population of Europe in particular. However, it can also be transmitted intravenously, such as through transfusions. The growing evidence of HEV contamination of blood products and documented cases of transmission have given rise to practice changes and blood product screening of HEV in many European countries. This review covers the abundant European literature and focuses on the most recent data pertaining to the prevalence of HEV RNA positivity and IgG seropositivity in the North American general population and in blood products from Canada and the United States. Currently, Health Canada and the Food and Drug Administration do not require testing of HEV in blood products. For this reason, awareness among blood product prescribers about the possibility of HEV transmission through blood products is crucial. However, we also demonstrate that the province of Quebec has a prevalence of anti-HEV and HEV RNA positivity similar to some European countries. In light of this, we believe that HEV RNA blood donation screening be reevaluated with the availability of more cost-effective assays.

Seroprevalence of transfusion-transmitted infections among blood donors in Makkah, Saudi Arabia.

INTRODUCTION: Blood donation is vital for healthcare; however, transfusion-transmitted infections (TTIs) pose a serious risk. This study investigated the seroprevalence of TTIs among Saudi blood donors. METHODOLOGY: This retrospective study included male blood donors aged ≥ 18 years who donated blood at Al-Noor Specialist Hospital in Makkah from January 2017 to December 2022. The blood units were screened for hepatitis B surface antigen (HBsAg) and core antibodies (HBc-IgG), hepatitis C antibodies (HCV-Abs), syphilis, HIV-1 antigen/antibody (HIV-1 Ag/Ab), human T-lymphotropic virus 1, 2 (HTLV-1/2), and malaria. RESULTS: There were 40,287 donors with an average age of 44.33 ± 18.12 years, and 62.3% (n = 25103) were Saudis. The overall rate of TTIs seropositivity was 7.4% (n = 2953); HBc-IgG (6.1%; n = 2473) was the most common, followed by HCV-Abs (0.4%; n = 177), and syphilis (0.34%; n = 136). All cases were negative for malaria, whilst HIV and HTLV positive donors were 0.06% (n = 24) and 0.13% (n = 52), respectively. Syphilis was more prevalent among non-Saudis (0.24%; n = 83) than among Saudis (0.1%; n = 53), whereas anti-HBc antibodies seropositivity was significantly higher among Saudi (3.4%; n = 1373) than non-Saudi donors (2.7%; n = 1100). CONCLUSIONS: Hepatitis B virus was the most frequently detected bloodborne pathogen, followed by hepatitis C virus and syphilis. Hepatitis B virus was also more prevalent among Saudi donors, whilst expatriates had higher rates of syphilis. Additional prospective multicenter studies are needed to accurately determine the prevalence of TTIs in Saudi Arabia.

Serological markers of transfusion transmissible infections and ABO blood groups in Najran, Saudi Arabia.

OBJECTIVES: To ascertain the prevalence of transfusion transmissible infections (TTIs) across diverse donor groups in the Najran province. Additionally, to establish a potential association between the development of TTI and the donors' blood group, as determined by the ABO/Rh blood grouping system. METHODS: Blood donation data of 4120 donors, spanning from January to December 2020, were retrospectively reviewed. The blood were screened for TTI markers, including hepatitis B surface antigen (HBsAg), anti-hepatitis B core (anti-HBc), anti-hepatitis C virus (anti-HCV), anti-human immunodeficiency viruses 1 and 2 (anti-HIV1&2), anti-human T-lymphotropic virus types 1 and 2 (anti-HTLV-1&2), and syphilis antigen. RESULTS: Positive TTI markers were detected in 10.9% of the donors. The most detected TTI marker was anti-HBc (8.9%), followed by HBsAg (0.7%). Other markers were individually detected in <1% of the donors. Anti-HBc-positive was significantly elevated among non-Saudi blood donors. There was an association between age groups and anti-HCV (p=0.002), anti-HTLV (p=0.004) and syphilis antigen (p=0.02) markers positivity. The AB positive blood group exhibited the most positivity for TTI markers, followed by O positive blood group. Similarly, association was found between ABO group and HBsAg (p=0.01), anti-HBc (p=0.001), and anti-HCV (p<0.001) markers positivity. CONCLUSION: Emphasis on implementing robust screening measures for donated blood is underscored by this study. There is the need for future study to extensively evaluate TTI status to enhance our understanding of the trend in TTI.

[Modern problems of plasma donation services: global experience in solving them].

As an analysis of foreign literature on donation has shown, the global market for therapy with drugs from human plasma is growing, which leads to the need for large volumes. With significant geographic imbalances in the global plasma supply and the dependence of most countries on plasma supplies from the United States, the most vulnerable are low- and middle-income countries, where the challenge of meeting the demand for plasma products requires improvements to regional plasma donation systems. An effective tool for the development of plasma collection services is compliance with the standards of plasma donation services, the development of voluntary free plasma donation, and the optimization of donor recruitment and retention processes.

Assessment of the COVID-19 pandemic progression in Ecuador through seroprevalence analysis of anti-SARS-CoV-2 IgG/IgM antibodies in blood donors.

Introduction: Coronavirus Disease 2019 (COVID-19) is a severe respiratory illness caused by the RNA virus SARS-CoV-2. Globally, there have been over 759.4 million cases and 6.74 million deaths, while Ecuador has reported more than 1.06 million cases and 35.9 thousand deaths. To describe the COVID-19 pandemic impact and the vaccinations effectiveness in a low-income country like Ecuador, we aim to assess the seroprevalence of IgG and IgM antibodies against SARS-CoV-2 in a sample from healthy blood donors at the Cruz Roja Ecuatoriana. Methods: The present seroprevalence study used a lateral flow immunoassay (LFIA) to detect anti-SARS-CoV-2 IgG and IgM antibodies in months with the highest confirmed case rates (May 2020; January, April 2021; January, February, June, July 2022) and months with the highest vaccination rates (May, June, July, August, December 2021) in Quito, Ecuador. The IgG and IgM seroprevalence were also assessed based on sex, age range, blood type and RhD antigen type. The sample size was 8,159, and sampling was performed based on the availability of each blood type. Results: The results showed an overall IgG and IgM seroprevalence of 47.76% and 3.44%, respectively. There were no differences in IgG and IgM seroprevalences between blood groups and sex, whereas statistical differences were found based on months, age range groups, and RhD antigen type. For instance, the highest IgG seroprevalence was observed in February 2022 and within the 17-26 years age range group, while the highest IgM seroprevalence was in April 2021 and within the 47-56 years age range group. Lastly, only IgG seroprevalence was higher in RhD+ individuals while IgM seroprevalence was similar across RhD types. Discussion: This project contributes to limited data on IgG and IgM antibodies against SARS-CoV-2 in Ecuador. It suggests that herd immunity may have been achieved in the last evaluated months, and highlights a potential link between the RhD antigen type and COVID-19 susceptibility. These findings have implications for public health strategies and vaccine distribution not only in Ecuador but also in regions with similar characteristics.

Performance of immunological assays for universal and differential diagnosis of HTLV-1/2 infection in candidates for blood donations from the Brazilian Amazon.

The present study compares the ability of distinct immunological assays (chemiluminescence immunoassay-CLIA, western blot-WB and flow cytometry-FC-Simplex and Duplex) to detect anti-HTLV (human T-lymphotropic virus) antibodies in candidates for blood donations at the Amazonas State Blood Center (Brazil) between January 2018 and December 2022. Overall, 257,942 samples from candidates for blood donations were screened using CLIA, which led to 0.15% seropositivity for HTLV (409 samples). A total of 151 candidates for blood donations were enrolled for retesting with CLIA followed by additional testing using WB and FC-Simplex and Duplex analysis. Our results demonstrated that 62% (93/151), 20% (30/151) and 17% (26/151) of the samples presented positive results with retesting using CLIA, WB and FC-Simplex analysis, respectively. Additional analysis of the CLIA, WB and FC-Simplex results revealed an overall agreement of 56% for CLIA and WB (22 co-negative; 30 co-positive samples), 48% for CLIA and FC-Simplex (21 co-negative; 24 co-positive samples) and 80% for WB and FC-Simplex (51 co-negative; 23 co-positive samples). Considering the WB as the reference standard for the diagnosis of infection with HTLV-1/2, we observed that the CLIA results of ≤3.0 RLU and >10.0 RLU in the retest can be used define a negative or positive result, respectively, and could be used as new specific cut-off values. The overall agreement between WB and FC-Duplex for accomplishing the differential diagnosis was evaluated and demonstrated 100% correspondence for the diagnosis of HTLV-1 (15/15) and HTLV-2 (7/7). Our findings demonstrate that gaps in the diagnosis of infection with HTLV-1/2 could be overcome by the simultaneous use of distinct immunological assays during retesting of candidates for blood donations.

Detection of Nucleocapsid Antibodies Associated with Primary SARS-CoV-2 Infection in Unvaccinated and Vaccinated Blood Donors.

Nucleocapsid antibody assays can be used to estimate SARS-CoV-2 infection prevalence in regions implementing spike-based COVID-19 vaccines. However, poor sensitivity of nucleocapsid antibody assays in detecting infection after vaccination has been reported. We derived a lower cutoff for identifying previous infections in a large blood donor cohort (N = 142,599) by using the Ortho VITROS Anti-SARS-CoV-2 Total-N Antibody assay, improving sensitivity while maintaining specificity >98%. We validated sensitivity in samples donated after self-reported swab-confirmed infections diagnoses. Sensitivity for first infections in unvaccinated donors was 98.1% (95% CI 98.0-98.2) and for infection after vaccination was 95.6% (95% CI 95.6-95.7) based on the standard cutoff. Regression analysis showed sensitivity was reduced in the Delta compared with Omicron period, in older donors, in asymptomatic infections, <30 days after infection, and for infection after vaccination. The standard Ortho N antibody threshold demonstrated good sensitivity, which was modestly improved with the revised cutoff.

Factors associated with blood donation among college and university students in Wuhan, China: structural equation model.

BACKGROUND: College and university students were an important population group of blood donors, especially in the current situation of tight blood supply. This study aimed to investigate the current status and determinants of blood donation among this population group in Wuhan using a structural equation model. METHODS: We conducted a cross-sectional study involving 12 colleges and universities in Wuhan, China, including 5168 students. Sociodemographic characteristics, health status, knowledge about blood donation, and attitude toward blood donation were treated as latent variables, with blood donation as the observed variable. Confirmatory factor analysis was conducted using the Mplus 8.0 statistical software application, followed by the establishment of a structural equation model to assess the relationships that exist between these variables. RESULTS: The overall blood donation rate among college and university students was 24.71%. The established model indicated that sociodemographic characteristics, health status, knowledge about blood donation, and attitude toward blood donation showed significant positive effects (0.135, 0.056, 0.321, and 0.389, respectively) on blood donation, among them, the direct effects were 0.076, -0.110, 0.143, and 0.389, respectively (P < 0.01). Additionally, sociodemographic characteristics, health status, and knowledge about blood donation had indirectly affected blood donation through the mediating effect of attitude towards blood donation. Their effects on attitude towards blood donation were 0.099, 0.243, and 0.468, respectively. (P < 0.01). The model could explain explained 22.22% of the variance in blood donation behavior among college and university students in Wuhan. CONCLUSION: Blood donation among college and university students in Wuhan was associated with sociodemographic characteristics, health status, knowledge about blood donation, and attitude towards blood donation, with attitude being the primary influencing factor. Tailored recruitment strategies for blood donation among students should prioritize initiatives aimed at enhancing knowledge about blood donation and fostering positive attitudes toward it.

Molecular detection and genotyping of human herpes virus 8 in blood donors in Congo.

OBJECTIVES: Human herpesvirus 8 (HHV8) is rarely studied in Congo, despite its prevalence in Africa. Among healthy individuals, HHV-8 does not always lead to a life-threatening infection; however, in immunocompromised individuals, it could lead to more severe disease. The distribution of HHV-8 genotypes varies depending on ethnicity and geographic region. METHOD: A prospective cross-sectional study included 265 samples from healthy blood donors from the National Blood Transfusion Center in Brazzaville, with an average age of 35 years, with extremes ranging from 18 to 60 years. After DNA extraction, a nested PCR was carried out for molecular detection, followed by genotyping by amplification of specific primers. RESULT: In this study, 4.9% were positive for molecular detection of HHV-8 DNA. All HHV-8 positive DNA samples that were subjected to genotyping by amplification with specific primers allowing discrimination of two major genotypes (A and B). Genotype A was identified in 5 (1.9%) samples and genotype B in 2 (0.7%) samples, indicating that both genotypes were predominant. The remaining viral DNA samples not identified as the major genotypes were classified as «indeterminate¼ and consisted of 6 (2.3%) samples. CONCLUSION: The results of the study suggest that Congo is an area where HHV-8 infection is endemic.

Irregular red blood cell antibodies, abnormal hemoglobin and dangerous universal blood donor insights from a public blood center in a Brazilian metropolitan area.

BACKGROUND: Immunohematology tests are crucial in transfusion safety. This study aimed to assess irregular red blood cell (RBC) antibodies, abnormal hemoglobin and dangerous universal blood donors at a public blood center in a Brazilian metropolitan area. METHODS: A cross-sectional study included all consecutive blood donors from January 2018 to December 2021 at the Brasília Blood Center Foundation, Federal District (FD), Brazil. RESULTS: Among 205,965 blood donations, irregular RBC antibodies were found in 743 (0.4 %). Abnormal hemoglobin was observed in 5396 (2.6 %): 3959 (1.9 %) with Hb AS, 1344 (0.7 %) with Hb AC, and 93 (< 0,1 %) with other hemoglobin variants. Of O group donors, 12.5 % (9646) had hemolysins: 12.5 % (2410) both anti-A and anti-B, 8.7 % (9646) only anti-A, and 1.6 % (1763) only anti-B hemolysins. Female sex (p < 0.001) and increasing age (p < 0.001) were associated with irregular RBC antibodies. O and/or Rh(D)-positive blood groups had a lower prevalence of irregular RBC antibodies compared to other ABO and/or Rh(D)-negative groups. Age (p < 0.001) and female sex (p < 0.001) were associated with anti-A/anti-B hemolysins, while FD residency was associated with reduced incidence (p < 0.001). CONCLUSION: Anti-A/anti-B hemolysins in O group donors, abnormal hemoglobin and irregular RBC antibodies pose risks to transfusion practice and should not be overlooked. Advancing age, female sex, ABO blood group other than O, or Rh(D)- negative are independently associated with the presence of irregular RBC antibodies. Dangerous universal blood donors were associated with advanced age, female gender, Rh(D)-positive blood type, and individuals residing in a Brazilian state other than where the blood center was located.

Insight into hazards and control of transfusion-transmitted infections in Egypt: A narrative review.

Blood transfusion is a critical life-saving medical intervention, but it carries the risk of transfusion-transmitted infections (TTIs) that can lead to serious consequences. TTIs include viral, bacterial, parasitic, and prion infections, transmitted through asymptomatic donor blood, contamination of stored blood products, or transfusion-related immunosuppression. Recognized global agents posing challenges to blood safety include human immunodeficiency virus (HIV), hepatitis C virus (HCV), hepatitis B virus (HBV), Syphilis, etc. Emerging pathogens like SARS-CoV-2, hepatitis E, and others present additional risks. The residual risk of TTIs, representing the likelihood of infected donations passing screening tests, varies globally. High-income countries generally show lower prevalence rates than low-income countries. In Egypt, the estimated prevalence rates for HIV, HBV, HCV, and syphilis markers among the donors are 0.23 %, 0.76 %, 2.33 %, and 0.24 %, respectively. In Egypt, specific residual risk estimates are scarce, but prevalence rates for key infections highlight existing challenges. The World Health Organization promotes a global blood safety strategy, advocating for national blood systems, voluntary non-remunerated donors, and quality-assured testing. Despite these measures, the establishment of a haemovigilance system which is critical for monitoring and preventing adverse events, including TTIs, is reported as lacking in Egypt. This highlights the importance of comprehensive surveillance and safety measures in the blood donation process to ensure universal access to safe blood. Primary health care can play a pivotal role in preventing TTIs.

Improved efficiency using sequential automated immunoassays for syphilis screening in blood donors.

Using sequential immunoassays for the screening of blood donors is well described for viral serology testing but not for the screening of syphilis. In this study, we report the evaluation results and 2-year sequential testing data using two highly sensitive automated serology assays, the Alinity s Syphilis chemiluminescent immunoassay for screening, with all repeatedly reactive samples then tested on the Elecsys Syphilis electrochemiluminescence immunoassay. We screened 1,767,782 blood donor samples between 7 July 2021 and 6 July 2023 and found the Alinity false-positive rate to be low at 0.08% (1,456/1,767,782). The common false-positive rate between the two assays was also low (3.83%, 58/1,514). Concordantly reactive samples were further tested using a Treponema pallidum particle agglutination test, a rapid plasma reagin test, and a fluorescent treponemal antibody absorption test. There were 262/1,376 concordantly reactive Alinity and Elecsys blood donor samples with reactivity on one or more of the confirmatory tests. A total of 26/1,376 donors had a current syphilis infection, 152/1,376 reported a past history of syphilis and had been treated, and 84/1,376 did not report a past history of syphilis. We suggest that future studies could explore the use of sequential immunoassays to aid in the serodiagnosis for syphilis. IMPORTANCE: The serodiagnosis for syphilis usually follows two methodologies-a "traditional" algorithm using a non-treponemal test followed by confirmation using a treponemal test, or a "reverse" algorithm using a treponemal test followed by a non-treponemal test. There are limited reports in the literature of using a modified reverse algorithm (treponemal test followed by a second treponemal test), and to the best of knowledge, there are currently no published articles using two highly sensitive automated immunoassays to aid the serodiagnosis of syphilis. In addition, the Treponema pallidum particle agglutination (TPPA) assay is commonly used as a confirmatory test for the diagnosis of syphilis. With the withdrawal of the TPPA assay from Australia and presumably from the global market also, alternative testing algorithms are now required. This study provides proof of concept for using sequential immunoassays in the diagnosis of syphilis.