Reactive Donors Research Articles

Ferric Chloride Promoted Glycosidation of Alkyl Thioglycosides.

Reported herein is a new reaction for glycosylation with thioglycosides in the presence of iron(III) chloride. Previously, FeCl3 was used for the activation of thioglycosides as a Lewis acid co-promoter paired with NIS. In the reported process, although 5.0 equiv of FeCl3 are needed to activate thioglycosides most efficiently, no additives were used, and the reactions with reactive glycosyl donors smoothly proceeded to completion in 1 h at 0 °C. This work showcases a new direction in developing glycosylation methods using greener and earth-abundant activators.

Response Patterns and Behavior of Seropositive Blood Donors: A Comprehensive Analysis.

Background Blood transfusion services are vital in healthcare, ensuring a steady and safe supply of blood for patients in need. Identifying seropositive blood donors and understanding their response patterns and behaviors are critical for improving the safety and efficacy of blood transfusion practices. Aim Our study aims to determine the response rate and pattern of blood donors who test reactive for transfusion-transmitted infections (TTIs) and to understand the attitudes of reactive blood donors toward post-donation notification, follow-up, and counseling. Materials and methods Our study is retrospective audit analyzing the data record for a period of 24 months from October 2021 to October 2023 in the transfusion medicine department of a tertiary care hospital in southern India. All donations were screened for hepatitis B, hepatitis C, HIV, malaria, and syphilis. Results Of the total 8,276 donations during the study period, 117 (1.41%) were reactive for various TTIs. The highest prevalence was hepatitis B (0.61%), followed by hepatitis C (0.38%), then HIV (0.22%) and syphilis (0.14%). Of all the TTI reactive donors, 82 donors (70%) responded after communication, and the remaining 30% could not be contacted by any mode of communication. The most common reason for non-communication was the fabricated postal address given by the donors. Of the donors approached, 57 (48.7%) reinstated to our blood bank for further counseling and specific treatment. The donor's busy schedule and out-of-city residence were the main reasons for non-compliance with the follow-up protocol. Conclusion Informing donors of their serological status and providing post-donation counseling are crucial elements of blood transfusion protocol. Necessary knowledge about TTIs are to be instilled to the donors during the blood collection procedure. Moreover, its crucial for the donor to provide accurate demographic details aiding follow up and easy access during times of managing blood inventory.

Nitric oxide is involved in the cardioprotection of neonatal rat hearts, but not in neonatal ischemic postconditioning.

The cardioprotective effect of ischemic preconditioning (IPC) and ischemic postconditioning (IPoC) in adult hearts is mediated by nitric oxide (NO). During the early developmental period, rat hearts exhibit higher resistance to ischemia-reperfusion (I/R) injury, contain higher levels of serum nitrates, and their resistance cannot be further increased by IPC or IPoC. NOS blocker (L-NAME) lowers their high resistance. Wistar rat hearts (postnatal Days 1 and 10) were perfused according to Langendorff and exposed to 40 min of global ischemia followed by reperfusion with or without IPoC. NO and reactive oxygen species donors (DEA-NONO, SIN-1) and L-NAME were administered. Tolerance to ischemia decreased between Days 1 and 10. DEA-NONO (low concentrations) significantly increased tolerance to I/R injury on both Days 1 and 10. SIN-1 increased tolerance to I/R injury on Day 10, but not on Day 1. L-NAME significantly reduced resistance to I/R injury on Day 1, but actually increased resistance to I/R injury on Day 10. Cardioprotection by IPoC on Day 10 was not affected by either NO donors or L-NAME. It can be concluded that resistance of the neonatal heart to I/R injury is NO dependent, but unlike in adult hearts, cardioprotective interventions, such as IPoC, are most likely NO independent.

Clinical significance of viral markers testing by ELISA and Individual Donation Nucleic Acid Testing (ID-NAT) for blood screening in blood bank: Single center study in Egypt

Prevention of transfusion-transmitted viral infections and insurance of safe blood transfusion are the main goals of all blood banks worldwide. Despite the high sensitivity and specificity of currently used enzyme linked immunosorbent assay (ELISA) for hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) testing, viral transmission could still occur during the window period. Introducing viral individual donation nucleic acid testing (ID-NAT) can greatly decrease such risk providing an additional layer in securing blood transfusion. We aimed to assess the clinical significance of viral markers testing by ELISA and ID-NAT for blood screening in the Blood Bank of Suez Canal University Hospital. We studied all donations (2132) collected during a two-months period. Blood donor samples were screened by ELISA and ID-NAT tests for HBV, HCV, and HIV. Serological testing results for HCV by ELISA revealed 2,122 (99.5 %) negative donations compared to 2,131 (99.95 %) negative donations by ID-NAT testing. Of the positive ELISA samples, only one was NAT positive. For HBV ELISA testing, 2,115 (99.2 %) donations were negative, also by ID-NAT testing 2,115 (99.2 %) donations were HBV DNA negative. Out of the negative ELISA samples, two samples were ID-NAT reactive donors which were missed by serology assay being in the window period. HIV ELISA testing revealed negative 2,130 (99.9 %) donations while ID-NAT testing showed 2,131 (99.95 %) negative donations and one positive donation. In conclusion, this is the first study carried out in the Suez Canal and Sinai region, Egypt to assess the importance of ID-NAT implementation. The introduction of ID-NAT in blood banks is an effective method for increasing safety of the blood transfusion.

Prevalensi Penyakit Infeksi Menular Lewat Transfusi Darah (IMLTD) Darah Donor di UDD PMI Kota Surabaya Tahun 2018-2022

Transmission of infectious diseases is one of the risks in the blood transfusion process. The Blood Donor Unit (UDD), as a blood provider institution, must ensure that blood products distributed in the community are safe, especially from infectious diseases that can be transmitted through blood transfusion (TTI). UDD PMI Surabaya is a first-class UDD and CPOB-certified facility that serves blood needs not only in East Java but also as a reference for the Eastern Indonesia region. The location of UDD is in a big city, the number of donors is quite large, the coverage of the area of origin of donors and the target users of blood products is quite broad, and a complete screening test method are interesting factors to study regarding the prevalence of TTI disease. This study aims to determine the prevalence of infectious diseases transmitted through blood transfusion among blood donors in UDD PMI Surabaya in 2018–2022, as well as the sociodemographic characteristics of reactive donors. This research is a retrospective, descriptive study. Data for 2018–2022 comes from the in UDD PMI Surabaya database with total number of 639580 blood donors. The research results show that hepatitis B is a TTI disease with the highest prevalence compared to other TTI diseases. Most donors come from the 17–30 year age group who have reactive TTI test results, and this decreases with increasing age except for hepatitis B. Reactive donors are more dominated by women than men, except for HIV disease.

Establishing a screening strategy for non-discriminatory reactive blood donors by constructing a predictive model of hepatitis B virus infection status from a single blood center in China.

When employing the transcription-mediated amplification method for screening blood donors, there are some non-discriminatory reactive results which are screening assay reactive but HBV-DNA discriminatory assay negative. This raises concerns regarding the possibility of false positives among donors, which may lead to permanent deferral of blood donors and affect blood supply. This study aimed to elucidate the infection status of these non-discriminatory reactive blood donors and develop and validate a model to predict individualized hepatitis B status to establish an optimal screening strategy. Supplementary tests were conducted on initial non-discriminating reactive donations to determine their HBV infection status, including repeat testing, viral load, serological marker detection, and follow-up. Primary clinical variables of the donors were recorded. Based on the Akaike information criterion, a stepwise forward algorithm was used to identify the predictive factors for information and construct a predictive model. The optimal screening strategy was determined through cost-effectiveness analysis. At the Blood Center of Zhejiang Province, 435 cases of initial non-discriminatory reactive donations were collected over two successive periods and sub-categorized through repeated testing into the following three groups: non-repeated positive group, non-discriminated positive group, and non-repeated HBV-DNA positive group. The HBV discriminatory rate increased after repeated testing (110/435, 25.29%). According to supplementary tests, the HBV-DNA positivity rate was 65.52% (285/435), and occult HBV infection was a significantly different among groups (χ2 = 93.22, p < 0.01). The HBV serological markers and viral load in the non-repeated positive group differed from those in the other two groups, with a lower viral load and a higher proportion of false positives. The predictive model constructed using a stepwise forward algorithm exhibited high discrimination, good fit, high calibration, and effectiveness. A cost-effectiveness analysis indicated that utilizing repeated discriminatory testing and the predictive model is an extremely beneficial screening approach for non-discriminatory reactive blood donors. Nearly two-third (65.52%) of the non-discriminatory reactive blood donors were HBV-DNA positive. Our innovative approach of constructing a predictive model as a supplementary screening strategy, combined with repeated discriminatory experiments, can effectively identify the infection status of non-discriminatory reactive blood donors, thereby increasing the safety of blood transfusions.

Donor notification and impact of counselling of reactive blood donors in the blood centre of a tertiary care teaching hospital of Odisha in eastern India

To ensure blood safety in blood transfusion service, the practice of donor screening, donor notification and counselling is essential. The aim of the study was to analyse the response rate of notified reactive donors to counselling and to see the impact of donor notification on reactive donors. A observational descriptive cross-sectional study was conducted in the blood centre of department of Transfusion Medicine, MKCG Medical College and Hospital Berhampur, Odisha during the time period from January 2022 to December 2022. Data was collected from reactive blood donor counselling register. Sero-reactive donors were contacted telephonically. Those who turned up into blood centre were counselled again and referred to appropriate centre for further management. The statistical analysis was done using percentages based on descriptive analysis.Out of total 32700 donations over a period of one year, 726 (2.22%) were reactive donors. Out of the total 726 donors, 496 (68.31%) donors could be notified telephonically, rest 230 could not be notified due to several reasons. Out of 496, 352(48.48%) were responders, who were counselled and referred to higher centres for further management. The response rate was 48.48%. Only 24 sero-reactive donors could be followed up. Pre-donation counselling, appropriate TTI screening test, donor notification and post donation counselling all together form a vital link between blood donors and blood safety, however the gap still exists.

Prevalence of Transfusion-transmissible Infections in Blood Donors: A Private Hospital Experience

Introduction: Blood transfusion, a vital component of established medical protocols, has the potential to save lives and enhance well-being. Nonetheless, it carries inherent risks, with transfusion-transmissible infections (TTIs) remaining a global public health concern. Vigilant monitoring of TTI prevalence among blood donors and understanding of evolving patterns are crucial safety endeavours. The objective of this study was to assess the prevalence of TTIs and their patterns among blood donors within a private hospital’s transfusion service. Methods: This retrospective study involved TTI testing results of blood donations at Normah Medical Specialist Centre (NMSC) in Kuching, Sarawak, spanning a decade from 2010 to 2019. Results: A total of 7329 blood donors contributed 16,085 blood units (2010 – 2019). Among them, 353 donors exhibited reactivity to TTIs, resulting in a prevalence of 4.81%. The majority of reactive donors were male (87.3%), of Malay ethnicity (62.6%), and first-time donors (73.9%). The prevalence rates were highest for HCV (2.69%), followed by HBV (1.41%), HIV (0.42%), and syphilis (0.39%). Both HBV and HCV demonstrated declining prevalence trends, while the prevalence of HIV and syphilis remained consistently low. The response to notification of positivity among reactive donors stood at a mere 4.0%, and the seroconversion rate among repeat donors reached 36.9%. No significant disparities in prevalence or response rates were observed between first-time and repeat donors. Conclusions: The prevalence of TTIs within NMSC’s blood donor populace remains relatively low, though not negligible. The responsiveness of reactive donors to notifications displayed considerable deficiencies.

Suggested blood donor deferral strategy regarding hepatitis B infections in China.

Hepatitis B virus (HBV) reactivity in individual immunologic and nucleic acid tests (NAT) tests does not represent the true infectious status of the blood donor. This study discusses the use of confirmatory tests to determine when deferral of blood donors is appropriate. HBsAg or HBV NAT reactive samples were confirmed via a neutralisation test. All the HBsAg reactive but neutralisation test negative samples were subjected to further anti-HBc testing. The receiver operating characteristic curve was used to obtain the best threshold value using signal-to-cut-off ratios of two HBsAg enzyme-linked immunosorbent assay reagents. Of the 780 HBV reactive samples collected, there were 467 HBsAg reactive but HBV DNA negative samples, of which 65 (13.92%) and 402 (86.08%) were neutralisation test positive and negative, respectively. Of the 402, 91 samples (30% of tested samples) were anti-HBc reactive. HBV DNA positive specimens negative by virus neutralisation were >80% HBcAg positive. A screening strategy was proposed for Chinese blood collection agencies. These findings suggest that adopting a screening algorithm for deferring HBV reactive blood donors based on HBsAg and NAT testing followed with HBsAg S/CO consideration and HBcAg testing can be both safe and feasible in China.

Targeting IDH2R140Q and other neoantigens in acute myeloid leukemia

AbstractFor patients with high-risk or relapsed/refractory acute myeloid leukemia (AML), allogeneic stem cell transplantation (allo-HSCT) and the graft-versus-leukemia effect mediated by donor T cells, offer the best chance of long-term remission. However, the concurrent transfer of alloreactive T cells can lead to graft-versus-host disease that is associated with transplant-related morbidity and mortality. Furthermore, ∼60% of patients will ultimately relapse after allo-HSCT, thus, underscoring the need for novel therapeutic strategies that are safe and effective. In this study, we explored the feasibility of immunotherapeutically targeting neoantigens, which arise from recurrent nonsynonymous mutations in AML and thus represent attractive targets because they are exclusively present on the tumor. Focusing on 14 recurrent driver mutations across 8 genes found in AML, we investigated their immunogenicity in 23 individuals with diverse HLA profiles. We demonstrate the immunogenicity of AML neoantigens, with 17 of 23 (74%) reactive donors screened mounting a response. The most immunodominant neoantigens were IDH2R140Q (n = 11 of 17 responders), IDH1R132H (n = 7 of 17), and FLT3D835Y (n = 6 of 17). In-depth studies of IDH2R140Q-specific T cells revealed the presence of reactive CD4+ and CD8+ T cells capable of recognizing distinct mutant-specific epitopes restricted to different HLA alleles. These neo–T cells could selectively recognize and kill HLA-matched AML targets endogenously expressing IDH2R140Q both in vitro and in vivo. Overall, our findings support the clinical translation of neoantigen–specific T cells to treat relapsed/refractory AML.

The importance of confirmatory assays in testing blood donors for human T-cell lymphotropic virus.

Serological HTLV-1/2 screening is mandatory for blood donor candidates in Brazil. Our objective was to analyse HTLV test results in blood donors submitted for screening and confirmatory assays in a Brazilian blood bank. Retrospective analysis (2017-2022) results of chemiluminescence immunoassays and confirmatory tests for HTLV-1/2 in reactive donors were performed. During the analysed period, three sets of assays were used: (1) Architect rHTLV-I/II + HTLV Blot 2.4 (Western blot [WB]); (2) Alinity s HTLV I/II Reagent Kit + INNO-line immunoassay (LIA) HTLV I/II Score (LIA); (3) Alinity + WB. The analysed period comprised a total of 1,557,333 donations. The mean percentage of HTLV reactive donors using the Architect assay was 0.14%. With the change to the Alinity assay, that percentage dropped 2.3-fold (0.06%). The reactivity rate in the confirmatory tests (1064 samples) ranged from 13.5% to 30.2%, whereas 58.3%-85.9% of samples were non-reactive. The highest rates of positive (30.2%) and indeterminate (11.5%) results were seen using LIA. Considering all analysed samples, those with signal/cut-off ratio (S/CO) >50 were positive in confirmatory tests (positive predictive value, PPV = 100%), whereas samples with S/CO ≤6 are very unlikely to be truly positive (PPV = 0). The use of the Alinity assay reduced the frequency of false-positive results. Confirmatory tests are important to identify true HTLV infection in blood donors, because more than 58% of initially reactive individuals are confirmed as seronegative. Categorizing S/CO values is useful for assessing the likelihood of true HTLV-1/2 infection.

Glycosyl oxazolines serve as active donors for iterative synthesis of type I oligosaccharides.

Synthesis of Galβ1 → 3GlcNAc-repeating saccharides is limited mainly by the formation of less-reactive oxazolines. We herein report an expeditious approach that requires trichloroacetyloxazolines as reactive glycosyl donors. Using only two disaccharide building blocks, the iterative oxazoline formation and glycosylation synthesized hexa- and octasaccharides with overall yields of 47% and 26% in four and six steps, respectively.

Notification and follow-up of blood donors reactive for transfusion-transmitted infections: A narrative review of the literature from India.

Notifying blood donors of their reactive status for transfusion-transmitted infections (TTIs) plays a vital role in enabling early diagnosis and management while also preventing these donors from making future donation and transmission of the infectious agent. Given the limited data on donor notification processes in India, a narrative review was conducted to assess the existing notification process and identify areas requiring enhancement. We conducted literature searches using PubMed, Google Scholar and Scopus, employing various keywords. The review included data on the year of the study, study design, donor numbers, TTI screening methods, sero-reactive donor confirmation, notification frequency and methods, donor responses, post-test counselling and risk factor assessment. Out of the 29 identified articles, 16 studies were included in the analysis. Repeat testing for initially reactive results was conducted in nine studies for 24.3% reactive donors. Phone calls were the primary notification method in most studies (8; 50%), with letters sent in cases of no response. Only 12 studies provided data on notified donors, revealing a notification rate of 71.2%. Of all initially reactive donors, 33.3% sought post-test counselling. Data from six studies indicated that 74.3% of responsive donors had identifiable TTI risk factors. Our review revealed significant variability in the notification processes across different studies. To enhance the management of TTI-reactive donor notifications and responses, we recommend the establishment of universal protocols encompassing pre-donation counselling, repeat/confirmatory testing, notification methods and comprehensive follow-up and treatment.

Analysis of the reentry status of blood donors with reactive bloodborne pathogen screening markers in Hangzhou City

Objective: To explore the reentry rate of reactive blood donors in the bloodborne pathogen infection screening in Hangzhou City, and analyze the donation behavior of those who successfully returned. Methods: A retrospective analysis of the return data of blood donors with reactive bloodborne pathogen screening markers was conducted at Zhejiang Provincial Blood Center from June 2017 to May 2022. The reentry process for blood donors with reactive bloodborne pathogen screening markers in Hangzhou City is as follows: after the initial screening period of 6 months, donors can voluntarily apply for return to the blood center. Samples are collected and subjected to routine enzyme-linked immunosorbent assay (ELISA) screening for HBsAg, anti-HCV, HIV Ab/Ag, and anti-TP, as well as a single nucleic acid (HIV/HCV/HBV) test. For samples that show non-reactivity in both ELISA and nucleic acid tests, serum biomarker testing for the reasons of exclusion is performed using chemiluminescence immunoassay (CLIA), and those with non-reactivity are allowed to return. Results: A total of 4 583 reactive blood donors who met the criteria for re-entry applied for reentry, out of which 475 applications were received from donors in the Hangzhou area. Among these, 279 donors were successfully readmitted, resulting in a success rate of 58.74% (279/475). By the end of December 2021, out of the 174 donors who successfully returned, 114 donors chose to donate again. They collectively donated 39 530 ml of whole blood and 1 147.2 therapeutic doses of platelets. Among these, 21 donors once again showed reactivity for pathogen infection biomarkers, accounting for 18.42% (21/114). Conclusion: The reentry strategy has somewhat mitigated the attrition of blood donors. Nevertheless, there are instances where donors who were successfully readmitted show reactivity once more in the screening for pathogen infection biomarkers.

An increase of human immunodeficiency virus infection amongs blood donor during COVID-19 pandemic

Human immunodeficiency virus (HIV) is a one of crucial concern to blood safety because of their prolonged presence in the blood. Unsafe blood transfusion from infected donor contribute to spread the virus as well. Indonesia health ministry reported that HIV infection increase significantly in 2019 to 2021, and HIV case diagnose in population still way from the prediction in 2020, only 78.7% cases reported from 90% prediction case. A retrospective cross-sectional study was conducted and collected 51,351 blood donors during COVID-19 pandemic, 2020-2021. Blood sample analyzed using serological methods to detect the present of HIV antibodies. A reactive result of HIV screening from 21,260 donor in 2020 showed 12 donors reactive (0.00056%), while in 2021 from 30,091 donor showed 42 donors reactive (0.142899%) and showed a significant different from 2020 and 2021 (p-value &amp;lt;0.05). The number of reactive donors increase numerously from 2020 to 2021, while total donor also increased. The level of social restriction has contribution of HIV reactive case among blood donor and showed from two years of pandemic with p-value &amp;lt;0.05. A significant increase of HIV infection among blood donor and the effect of restriction level to prevent COVID-19 transmission are clearly show in this study.

Analysing Factors Responsible for Transfusion Transmitted Infections (TTIs) among Reactive Blood Donors in a Blood Centre of Himachal Pradesh (H. P.): A Retrospective Data Analysis

Analysing Factors Responsible for Transfusion Transmitted Infections (TTIs) among Reactive Blood Donors in a Blood Centre of Himachal Pradesh (H. P.): A Retrospective Data Analysis

Regio- and Stereoselective C-Glycosylation of Indoles Using o-[1-(p-MeO-Phenyl)vinyl]benzoates (PMPVB) as Glycosyl Donors under Brønsted Acid Catalysis

The alkene-based o-[1-(p-MeO-phenyl)vinyl]benzoates (PMPVB) donors that can be remotely activated under catalytic Brønsted acidic conditions have been utilized to synthesize the C-linked indolyl glycosides in a regio- and stereoselective manner. The highly reactive glycosyl donors allow the usage of the poorly nucleophilic N-Boc and N-acetyl indole derivatives, leading to the indolyl glycosides in excellent yields and stereoselectivities. Also, conditions were developed for recycling the byproduct, which significantly improves the potential of these donors.

Prevalence and Trends of Transfusion Transmitted Infections among Voluntary Blood Donors in a Blood Bank of Tertiary Care Hospital in Nagpur, 2017-2021

Background: Blood transfusion is an effective treatment that saves millions of lives. Nevertheless, transfusion transmitted infections (TTIs) are a major problem. The aim of this study is to assess the prevalence and trends of TTI in healthy blood donors in tertiary care hospital blood banks and compare it with national data and other studies in different regions. Methods: A retrospective cross-sectional study was conducted from January 2017 to December 2021 in healthy donors aged between 18 to 65 years. TTIs tests were performed using CLIA (Chemiluminescent Immunoassay) for HIV, HBV, HCV, and HBsAg, and RPR (Rapid Plasma Rea-gin) for syphilis. Results: Of the 12,193 normal healthy donors enrolled in this study, 124 (1.01%) donors were sero-reactive to various TTIs. Of the 124 donors, 11 (0.09%) were seropositive for HIV, 13 (0.106%) for HCV, 95 (0.7%) for HBsAg, and 5 (0.04%) for VDRL. There were no reactive donors for malaria. The most common age group for sero-reactivity was 21–30 years (50.8%) of all seropositive donors. Conclusion: The overall positive rate for all test combinations for TTI showed a steady trend with a gradual decrease from 2017 to 2021. We should raise public awareness and target people in their 21s to 30s, and contribute to safe blood transfusion.

Activation of Thioglycosides with Copper(II) Bromide.

Reported herein is a new protocol for glycosidation of alkyl and aryl thioglycosides in the presence of copper(II) bromide. While the activation with CuBr2 alone was proven suitable for reactive glycosyl donors, the activation of less reactive donors was more efficient in the presence of triflic acid as an additive. A variety of thioglycoside donors in reactions with different glycosyl acceptors were investigated to determine the initial scope of this reaction.

UTILITY OF MINI-POOL NAT STRATEGY FOR IMPROVING BLOOD SAFETY BY DETECTING OCCULT HEPATITIS B VIRUS INFECTION : A 5 YEAR STUDY

Introduction: The prevalence of transfusion transmitted infections (TTIs) is high in India. The aim of our study was to evaluate the sero-prevalence of TTIs using Nucleic acid technology (NAT) and detection of Occult Hepatitis B virus infection by Minipool NAT Strategy. A total of 89,639 units of blood donated at Dhanvanta Materials and Methods: ri Voluntary Blood Bank, Rajahmundry during the period from January 2012 to July 2016. The sero-prevalence for HIV, HBV and HCV was tested by 4th generation ELISA. Only sero-negative samples were tested on mini pool nucleic acid test (MP-NAT) to detect HIV1, HIV2, HCV and HBV viral nucleic acids. Combined NAT yield was calculated and compared the NAT yield with MPX test and MPX V2.0. We also evaluated the optical density (OD) values of ELISA for MP-NAT reactive donor samples to evaluate the efcacy of NAT in detecting window period cases. The Results: overall sero-prevalence of TTIs was 2.41% and HBV was predominantly present (66%). Total 29 ELISA negative blood donor samples were found reactive on NAT. All NAT reactive donors were of HBV only. Out of 29 cases, 12 were detected by MPX test from 26,008 donations and 17 by MPX V2.0 from 25,619 donations, providing NAT yield of 1:2169 and 1:1507 respectively. OD and Signal cut off values of ELISA for NAT reactive samples were found to be much below extended grey zone value (&lt;0.3). Additiona Conclusion: l testing of nucleic acids by MP-NAT in combination of mandated primary serology by ELISA provides 99.99% of safe blood to needy patients; thus signicantly reduces the risk of TTIs by identifying the window period cases.