Transfusion-transmitted Infectious Diseases Research Articles

International review of blood donation screening for anti-HBc and occult hepatitis B virus infection.

Hepatitis B core antibody (anti-HBc) screening has been implemented in many blood establishments to help prevent transmission of hepatitis B virus (HBV), including from donors with occult HBV infection (OBI). We review HBV screening algorithms across blood establishments globally and their potential effectiveness in reducing transmission risk. A questionnaire on HBV screening and follow-up strategies was distributed to members of the International Society of Blood Transfusion working party on transfusion-transmitted infectious diseases. Screening data from 2022 were assimilated and analyzed. A total of 30 unique responses were received from 25 countries. Sixteen respondents screened all donations for anti-HBc, with 14 also screening all donations for HBV DNA. Anti-HBc prevalence was 0.42% in all blood donors and 1.19% in new donors in low-endemic countries; however, only 44% of respondents performed additional anti-HBc testing to exclude false reactivity. 0.68% of anti-HBc positive, HBsAg-negative donors had detectable HBV DNA. Ten respondents did universal HBV DNA screening without anti-HBc, whereas four respondents did not screen for either. Deferral strategies for anti-HBc positive donors were highly variable. One transfusion-transmission from an anti-HBc negative donor was reported. Anti-HBc screening identifies donors with OBI but also results in the unnecessary deferral of a significant number of donors with resolved HBV infection and donors with false-reactive anti-HBc results. Whilst confirmation of anti-HBc results could be improved to reduce donor deferral, transmission risks associated with anti-HBc negative OBI donors must be considered. In high-endemic areas, highly sensitive HBV DNA testing is required to identify infectious donors.

Characterization of transfusion-relevant bacteria reference strains in a lyophilized format.

Blood safety measures used by blood establishments to increase blood component safety can be validated using Transfusion-Relevant Bacterial Reference Strains (TRBRS). Ultra-cold storage conditions and manual preparation of the current TRBRS may restrict their practical use. To address this issue, the ISBT Transfusion-Transmitted Infectious Diseases Working Party's Bacterial Subgroup organized an international study to validate TRBRS in a user-friendly, lyophilised format. Two bacterial strains Klebsiella pneumoniae PEI-B-P-08 and Staphylococcus aureus PEI-B-P-63 were manufactured as lyophilised material. The lyophilised bacteria were distributed to 11 different labs worldwide to assess the robustness for enumeration, identification and determination of growth kinetics in platelet concentrates (PCs). Production of lyophilised TRBRS had no impact on the growth properties compared with the traditional format. The new format allows a direct low-quantity spiking of approximately 30 bacteria in PCs for transfusion-relevant experiments. In addition, the lyophilised bacteria exhibit long-term stability across a broad temperature range and can even be directly rehydrated in PCs without losing viability. Interlaboratory comparative study demonstrated the robustness of the new format as 100% of spiked PC exhibited growth. Lyophilised TRBRS provide a user-friendly material for transfusion-related studies. TRBRS in the new format have improved features that may lead to a more frequent use in the quality control of transfusion-related safety measures in the future.

A comparative analysis of screening technologies for transfusion-transmitted infectious diseases

Abstract: BACKGROUND AND OBJECTIVES: Ensuring the safety of blood supply relies on robust screening and donor selection processes. This study assessed the technical performance of automated enzyme-linked immunosorbent assay (ELISA) (EVOLIS, Bio-Rad, France) and electrochemiluminescence immunoassay (ECLIA) (COBAS 6000 e601 and COBAS e411, Roche Diagnostics, Germany) in detecting hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infections. MATERIALS AND METHODS Retrospective data of transfusion transmissible infections (TTI) screening test results were collected from blood center records, encompassing two phases: January 2020 to May 2020 (phase 1) and March 2021 to April 2021 (phase 2). The sensitivity, specificity, positive predictive value, and negative predictive value of ELISA and ECLIA were calculated. Performance evaluation was conducted using the Youden’s index and the kappa coefficient. RESULTS: The study included a total of 824, 755, and 830 donor samples in phase 1 and 1237, 1238, and 1236 donor samples in phase 2 for HIV, HBV, and HCV testing, respectively. High agreement (kappa 0.88, 0.95) existed between ELISA and COBAS e601 for HIV and HBV, with substantial agreement (kappa 0.66) for HCV. Likewise, substantial agreement (kappa 0.66, 0.79, 0.79) was found between ELISA and COBAS e411 for all three parameters HIV, HBV and HCV, respectively. Notably, nearly all false-positive samples detected by ECLIA had low cutoff index values ranging from 1 to 6.5. CONCLUSION: The differences in sensitivity and specificity contribute to the discrepancy observed between various serological testing platforms, such as ELISA and ECLIA, for TTI testing. Specifically, low signal/cutoff ratios ≤6.5 obtained with ECLIA are highly indicative of false-positive results.

An international review of the characteristics of viral nucleic acid-amplification testing (NAT) reveals a trend towards the use of smaller pool sizes and individual donation NAT.

Nucleic acid-amplification testing (NAT) is used for screening blood donations/donors for blood-borne viruses. We reviewed global viral NAT characteristics and NAT-yield confirmatory testing used by blood operators. NAT characteristics and NAT-yield confirmatory testing used during 2019 was surveyed internationally by the International Society of Blood Transfusion Working Party Transfusion-Transmitted Infectious Diseases. Reported characteristics are presented herein. NAT was mainly performed under government mandate. Human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) NAT was performed on all donors and donation types, while selective testing was reported for West Nile virus, hepatitis E virus (HEV), and Zika virus. Individual donation NAT was used for HIV, HCV and HBV by ~50% of responders, while HEV was screened in mini-pools by 83% of responders performing HEV NAT. Confirmatory testing for NAT-yield samples was generally performed by NAT on a sample from the same donation or by NAT and serology on samples from the same donation and a follow-up sample. In the last decade, there has been a trend towards use of smaller pool sizes or individual donation NAT. We captured characteristics of NAT internationally in 2019 and provide insights into confirmatory testing approaches used for NAT-yields, potentially benefitting blood operators seeking to implement NAT.

International review of blood donation nucleic acid amplification testing.

Nucleic acid amplification testing (NAT), in blood services context, is used for the detection of viral and parasite nucleic acids to reduce transfusion-transmitted infections. This project reviewed NAT for screening blood donations globally. A survey on NAT usage, developed by the International Society of Blood Transfusion Working Party on Transfusion-transmitted Infectious Diseases (ISBT WP-TTID), was distributed through ISBT WP-TTID members. Data were analysed using descriptive statistics. Forty-three responses were received from 32 countries. Increased adoption of blood donation viral screening by NAT was observed over the past decade. NAT-positive donations were detected for all viruses tested in 2019 (proportion of donations positive by NAT were 0.0099% for human immunodeficiency virus [HIV], 0.0063% for hepatitis C virus [HCV], 0.0247% for hepatitis B virus [HBV], 0.0323% for hepatitis E virus [HEV], 0.0014% for West Nile virus [WNV] and 0.00005% for Zika virus [ZIKV]). Globally, over 3100 NAT-positive donations were identified as NAT yield or solely by NAT in 2019 and over 22,000 since the introduction of NAT, with HBV accounting for over half. NAT-positivity rate was higher in first-time donors for all viruses tested except WNV. During 2019, a small number of participants performed NAT for parasites (Trypanosoma cruzi, Babesia spp., Plasmodium spp.). This survey captures current use of blood donation NAT globally. There has been increased NAT usage over the last decade. It is clear that NAT contributes to improving blood transfusion safety globally; however, there is a need to overcome economic barriers for regions/countries not performing NAT.

Microbiological environmental contamination in the blood supply chain: An international survey by the bacterial subgroup of the ISBT Transfusion-Transmitted Infectious Diseases Working Party.

Blood transfusion centres ensure the quality and safety of transfusable blood components. However, septic transfusion reactions involving environmental contaminants occur. An international survey issued by the ISBT Transfusion-Transmitted Infectious Diseases Working Party (ISBT-TTID-WP) Bacterial Subgroup aimed to collect information regarding microbiological environmental monitoring from transfusion services. A Form survey (English and Spanish) with 35 questions was sent to ISBT-TTID-WP members. The survey had four sections: (1) respondent personal information, (2) cleaning/disinfection practices during blood component manufacturing, (3) cleaning/disinfection practices during blood component storage and (4) blood component storage bag integrity. Respondents completed the survey electronically, and data were comparatively analysed using Microsoft Excel. There were 49 responses from 20 countries. Five of 49 sites manufacture blood components in a cleanroom, and most use personal protective equipment, although the type varied between sites. Approximately 40% of sites perform environmental monitoring during blood component production, with seven sites providing details about frequency and methods. Most (~94%) centres have procedures for cleaning/disinfection of processing and storage facilities with varying responses regarding areas, frequency and methods. Inconsistency was reported regarding the orientation of platelet component incubation (portrait vs. landscape). Over 93% of sites assess storage bag integrity and report damage to manufacturers, and 49% of centres report septic transfusion reactions potentially linked to damaged storage containers. Data from this survey highlight the need for consensual guidelines for transfusion services regarding cleaning and disinfection practices. Environmental monitoring could be adopted to minimize the risk of blood component contamination for transfusion patient safety.

Monitoring viral genomic sequences in transfusion-transmitted viruses.

Monitoring genomic sequences of blood-borne viruses infecting blood donors enables blood operators to undertake molecular epidemiology, confirm transfusion transmission and assess and characterize molecular and serological screening assays. The purpose of the study was to determine how blood operators globally value viral diversity surveillance and to assess its impact. An electronic questionnaire was developed and circulated to members of the International Society of Blood Transfusion-transmitted infectious diseases working party. Responses were compiled and complete data sets were analysed. Ninety-seven percent of respondents agreed that monitoring viral genomic sequences was important to blood operators and the transfusion community. However, only 47% of respondents are currently doing this monitoring. The main limitations reported were a lack of financial resources and expertise. Sequencing techniques, primarily next-generation sequencing and also Sanger sequencing, were considered most appropriate, with the preferred option for testing being regional or national reference centres. Respondents agreed that engagement with public health authorities needs to be enhanced. Monitoring genomic sequences of blood-borne viruses is widely considered important by the transfusion community because of its direct applications for transfusion safety, and beyond for public health in general. Therefore, there is a need to strengthen collaboration between blood operators and public health authorities. While national and regional reference centres may be the most appropriate structure for such testing, international collaborations should not be overlooked. Overcoming financial barriers will be an important hurdle for many.

Frequency of Transfusion Transmitted Infections in Healthy Blood Donors in a Tertiary Care Hospital

Objective: To determine transfusion transmitted infectious disease (TTI) pattern in potential healthy replacement donors. Study Design: Cross sectional study Place and Duration: Diagnostic and Research Laboratory Liaquat University of Medical and Health Sciences Jamshoro, Hyderabad. Jan-2022-Dec 2022 Methods: Total 14,355 replacement donors of age 18-55 years were selected in this study as per inclusion criteria, which comprised of 25 questionnaire, evaluating donors for history of Injections, medicines, time since last donation, tattoos, not feeling well, dental work, sexual relationships, history of malaria / T.B, surgery, jaundice vaccination positive viral markers in the past followed by physical examination. SPSS 24.0 was used to analyze all data. Results: There were 9635 (67.1%) males and 4720 (32.95) females in this study. Among all, 42.8% cases had age 18-25 years, 26.8% cases had 26-30 years, 16.6% cases had 31-35 years and 13.7% patients were from age group 36-55 years. Majority of the donors 32.3% had blood group B positive, followed by O positive in 29.9%, 22% donors had A positive and AB positive blood group found in 8.7% cases. According to screening results, most common infection was Hepatitis B Core Antibody found in 10% cases, anti-HCV found in 2.17% cases, HBsAg in 0.3% cases, ICT malaria in 0.05% cases, RPR 0.41% and HIV 1&2 in 0.1% cases. Conclusion: HB core total antibody showed highest positivity in replacement donors despite stringent donor selection criteria, followed by Anti HCV. Syphilis, HBsAg, HIV and malaria showed lowest prevalences. Keywords: Blood Donors, HCV, HBV, ICT Malaria

Reducing the risk of transfusion-transmitted infectious disease markers in blood and blood component donations: Movement from remunerated to voluntary, non-remunerated donations in Lithuania from 2013 to 2020.

Lithuania has a long history of remunerated donations. The first steps towards voluntary, non-remunerated blood and blood component donations started in 2004. Lithuania achieved 99.98% voluntary non-remunerated donations (VNRDs) in 2020. This study aimed to assess the risk of transfusion-transmitted infectious (TTI) disease markers for remunerated donations in comparison with VNRDs in Lithuania from 2013 to 2020. Data were obtained from the Lithuanian Blood Donor Register. The prevalence was calculated as the rate between the number of confirmed positive results for all TTI disease markers (serological anti-HCV, HBsAg, Ag/anti-HIV 1 and 2, and syphilis, and/or HCV, HBV, and HIV-1 NAT) per 100 donations. The relative risk of infectious disease markers for remunerated donations was then estimated. In total, 796310 donations were made. Altogether, 2743 donations were positive for TTI markers as follows: HCV, 1318; HBV, 768; syphilis, 583; and HIV 1 and 2, 74. The prevalence of confirmed TTI markers were 2.86, 0.97, 0.18, and 0.04 per 100 first-time remunerated donations, first-time VNRDs, repeat remunerated donations, and repeat VNRDs, respectively. Remunerated first-time and repeat donations had a statistically higher prevalence of TTI disease markers than VNRDs. First-time and repeat remunerated donations had statistically significantly higher relative risks of confirmed TTI disease markers than VNRD. In conclusion, the risks of TTI disease markers for remunerated first-time and repeat blood and its component donations are significantly higher than those for VNRDs.

Residual risk estimates of transfusion transmissible hepatitis B, hepatitis C and human immunodeficiency virus using nucleic acid testing yield/window period model in an Indian setting.

Estimation of residual risk (RR) is necessary to understand status of blood safety with current testing strategies and need to improve it further. These estimates from India are lacking till date. Present study was aimed to estimate RR and incident rate (IR) of transfusion transmitted infectious disease (TTIDs) in Indian setting. Blood donor demographic data, serological testing results and nucleic acid testing (NAT) screening results were collected retrospectively from January 2015 to June 2017. Mathematical modelling using NAT yield/window period model was done to estimate IR and RR of TTIDs. Data was compared between different groups based on age-group, gender, donation repeatability and type of donor. A total 106 119 blood donors donated 109 441 units with overall TTID reactivity of 2.22%. HBV was most prevalent TTID (1.26%) with RR of 16.1 per million followed by HCV and HIV with RR of 4.4 and 3.1 per million donations, respectively. NAT testing variably reduced RR ranging from 69.4% to 96.1% depending on TTID. Younger, repeat and voluntary donors had significantly lower prevalence of TTIDs compared to older, first time and replacement donors. Gaps in the blood safety could be bridged significantly by implementing NAT testing and using quality serological assays. Comparatively high RR despite using quality serological assays and ID-NAT testing highlights need to develop long term strategies to improve blood safety by focusing on improving donor pool by recruiting regular voluntary donors among youth and imparting knowledge of healthy practices.

National Blood Foundation 2021 Research and Development summit: Discovery, innovation, and challenges in advancing blood and biotherapies.

National Blood Foundation 2021 Research and Development summit: Discovery, innovation, and challenges in advancing blood and biotherapies.

The international experience of bacterial screen testing of platelet components with automated microbial detection systems: An update.

In 2014, the bacterial subgroup of the Transfusion-Transmitted Infectious Diseases working party of ISBT published a review on the International Experience of Bacterial Screen Testing of Platelet Components (PCs) with an Automated Microbial Detection System. The purpose of this review, which is focused on publications on or after 2014, is to summarize recent experiences related to bacterial contamination of PCs and the use of an automated culture method to safeguard the blood supply. We first reviewed septic transfusion reactions after PC transfusion as reported in national haemovigilance systems along with a few reports from various countries on bacterial contamination of blood products. Next, we reviewed PC automated culture protocols employed by national blood services in the United Kingdom, Australia, Canada and large blood collection organization and hospital transfusion services in the United States. Then, we acknowledged the limitations of currently available culture methodologies in abating the risks of transfusion-transmitted bacterial infection, through a review of case reports. This review was neither meant to be critical of the literature reviewed nor meant to identify or recommend a best practice. We concluded that significant risk reduction can be achieved by one or a combination of more than one strategy. No one approach is feasible for all institutions worldwide. In selecting strategies, institutions should consider the possible impact on platelet components availability and entertain a risk-based decision-making approach that accounts for operational, logistical and financial factors.

International survey of strategies to mitigate transfusion-transmitted Trypanosoma cruzi in non-endemic countries, 2016-2018.

Chagas disease, caused by Trypanosoma cruzi, is endemic to Mexico, Central and South America. While initially limited to the Americas, emigration of infected persons triggered geographically broader blood safety challenges. To mitigate transfusion-transmitted Chagas (TTC), transfusion services implemented approaches including risk factor questions and serologic testing. We sought to understand and compare strategies in non-endemic countries. Transfusion services in International Society of Blood Transfusion (ISBT)-affiliated organizations and members of the ISBT Working Party on Transfusion-Transmitted Infectious Diseases were invited to complete an online survey on T. cruzi mitigation strategies. The survey queried about cases of TTC, risk factors, testing methodology, educational materials, pathogen reduction, donor/product management, donor deferral and perceived public health concerns surrounding TTC. Responses were received from 27 institutions in 22 countries. Most countries (77.3%) reported no historical TTC cases, while 18.2% reported 1-5 cases and 4.5% reported 6-10 cases. Concern about Chagas among the general public and public health authorities was low, but 12 of 25 blood centres reported moderate/high concern. Overall, 17 countries mitigated for TTC: 15 used risk factor questions and 10tested for T. cruzi antibodies. Ten countries used pathogen reduction but not specifically to prevent TTC. While Chagas is rarely cited as a public health concern, blood centres in many non-endemic countries, including those outside the Americas, implemented measures to mitigate risk. Mitigation focussed on risk factors associated with Latin American immigrants and serologic testing. Thus, despite the rarity of TTC, many non-endemic countries continue to address it as an ongoing blood safety risk.

Seroprevalence of Hepatitis B virus among blood donors at a tertiary care hospital in Gujarat

Introduction: Transfusion of blood and blood components, as a specialized modality of patient management saves millions of lives worldwide each year and reduces morbidity. Transfusion-transmitted infectious (TTIs) diseases remain a major topic of interest for those involved in blood safety. Screening of TTIs among blood donors is helpful to observe the seroprevalence of HBV among healthy blood donors. Materials and Methods: A cross-sectional study based on observance of records was conducted at Blood Bank of tertiary care hospital in Gujarat. Total 7,935 donors were screened over the period of year 2010 to 2017 according the guideline of WHO. Results: Blood units were collected from replacement donors (54.1%) and voluntary blood donors (45.9%). Male donors (97.4%) outnumbered female donors. Seroprevalence for HBV was found to be 0.98%. Conclusion: Replacement donors were higher in number than the voluntary donors. Stringent measures need to be taken on urgent basis including dissemination of information, mandatory screening protocol of blood and blood products with test having sensitivity and specificity, better donor recruitment, advocacy of voluntary donation, proper sterilization of instruments, proper disposal of contaminated material, and immunization of people at risk, particularly health care workers. Keywords: Blood Donors, HBV, Replacement Donors, Seroprevalence, Transfusion Transmitted Infection (TTIs), Voluntary Donors.

Complete Inactivation of Blood Borne Pathogen Trypanosoma cruzi in Stored Human Platelet Concentrates and Plasma Treated With 405 nm Violet-Blue Light.

The introduction of pathogen reduction technologies (PRTs) to inactivate bacteria, viruses and parasites in donated blood components stored for transfusion adds to the existing arsenal toward reducing the risk of transfusion-transmitted infectious diseases (TTIDs). We have previously demonstrated that 405 nm violet-blue light effectively reduces blood-borne bacteria in stored human plasma and platelet concentrates. In this report, we investigated the microbicidal effect of 405 nm light on one important bloodborne parasite Trypanosoma cruzi that causes Chagas disease in humans. Our results demonstrated that a light irradiance at 15 mWcm−2 for 5 h, equivalent to 270 Jcm−2, effectively inactivated T. cruzi by over 9.0 Log10, in plasma and platelets that were evaluated by a MK2 cell infectivity assay. Giemsa stained T. cruzi infected MK2 cells showed that the light-treated parasites in plasma and platelets were deficient in infecting MK2 cells and did not differentiate further into intracellular amastigotes unlike the untreated parasites. The light-treated and untreated parasite samples were then evaluated for any residual infectivity by injecting the treated parasites into Swiss Webster mice, which did not develop infection even after the animals were immunosuppressed, further demonstrating that the light treatment was completely effective for inactivation of the parasite; the light-treated platelets had similar in vitro metabolic and biochemical indices to that of untreated platelets. Overall, these results provide a proof of concept toward developing 405 nm light treatment as a pathogen reduction technology (PRT) to enhance the safety of stored human plasma and platelet concentrates from bloodborne T. cruzi, which causes Chagas disease.

SEROPREVALENCE OF HIV AND HBsAg AMONGST BLOOD DONORS IN A TERTIARY CARE HOSPITAL, CHHATTISGARH.

INTRODUCTION: India being the second highly populated nation in the world. HIV/AIDS has acquired pandemic proportion in the world. Estimate by WHO for current infection rate in Asia. India has the third largest HIV epidemic in the world. HIV prevalence in the age group 15-49 yrs was an estimate of 0.2%. India has been classified as an intermediate in the Hepatitis B Virus (HBV) endemic (HBsAg carriage 2-7%) zone with the second largest global pool of chronic HBV infections. Safety assessment of the blood supply, the quality of screening measures and the risk of transfusion transmitted infectious diseases (TTIs) in any country can be estimated by scrutinizing the files of blood donors. After the introduction of the blood banks and improved storage facilities, it became more extensively used. Blood is one of the major sources of TTIs like hepatitis B, hepatitis C, HIV, syphilis, and many other blood borne diseases. Disclosure of these threats brought a dramatic change in attitude of physicians and patients about blood transfusion. The objective of this study is to determine the seroprevalence of transfusion transmitted infections amidst voluntary blood donors at a rural tertiary healthcare teaching hospital in Chhattisgarh.
 MATERIAL AND METHODS: This retrospective study was carried out in Chandulal Chandrakar Memorial Medical College, Kachandur, Durg. Blood donors were volunteers, or and commercial donors who donated the blood and paid by patients, their families, or friends to replace blood used or expected to be used for patients from the blood bank of the hospital. After proper donation of blood routine screening of blood was carried out according to standard protocol. Laboratory diagnosis of HIV 1 and HIV 2 was carried out by ELISA test. Hepatitis B surface antigen was screened by using ELISA. RESULTS: A total of 1915 consecutive blood donors’ sera were screened at Chandulal Chandrakar Memorial Medical College, blood bank during study period. Of these 1914 were male and 1 female. The mean age of patients was found to be 29.34 years with standard deviation (SD) of 11.65 Years. Among all blood donors in present study, 759(39.63%) were first time donors and 1156(60.37%) were repeated donors. 1 patient was HIV positive in first donation group while 3 (75%) were positive in repeat donation group. 7 (38.9%) were HBsAg positive in in first donation group while 11(61.1%) were positive in repeat donation group. Two patients in first donation group had dual infection of HIV and HBsAg.
 CONCLUSION: Seropositivity was high in repeated donors as compared to first time donors. The incidence of HIV is observed to be 0.2% and that of HBsAg is 0.94%. Strict selection of blood donors should be done to avoid transfusion-transmissible infections during the window period.

Blood Safety in the United States: Prevention, Detection, and Pathogen Reduction

The safety and integrity of the blood supply is of paramount importance for delivering optimal medical care. Additionally, blood safety is of utmost importance to the United States public. Pathogen testing of donated blood products has been adapted and developed with the goal of eliminating the risk of transfusion-transmitted infectious disease. Currently, blood safety interventions are focused on excluding persons at risk for transfusion-transmissible infections from donating blood and on detecting the presence of transfusion-transmissible agents in donated blood. These interventions are intended to be complementary and function to isolate, and ideally, eliminate, the risk of exposure to known pathogenic agents by transfused blood components. We provide an overview of the strategies and techniques utilized to ensure the safety of the blood supply in the U.S.

Proceedings of the Food and Drug Administration public workshop on pathogen reduction technologies for blood safety 2018 (Commentary, p. 3026).

On November 29, 2018, experts in the field of infectious diseases, pathogen reduction technologies (PRTs) and other participants from blood centers, academia, and industry gathered at the Food and Drug Administration (FDA) White Oak Campus in Silver Spring, Maryland, for a 2‐day public workshop entitled “Pathogen Reduction Technologies for Blood Safety.” The workshop opened with welcome remarks from Dr. Nicole Verdun, Director, Office of Blood Research and Review (OBRR), Center for Biologics Evaluation and Research (CBER), FDA, followed by introductory remarks from Dr. Peter Marks, Director, CBER, FDA. The first day of the workshop focused on blood‐borne infectious agents and their impact on blood safety, experiences of the American Red Cross, and other blood establishments in implementing FDA‐approved pathogen inactivation (PI) technology for plasma and platelets (PLTs) in the United States and novel PRTs under consideration for whole blood (WB) and red blood cells (RBCs). The second day opened with welcome remarks from Dr. Chintamani Atreya, Associate Director for Research, OBRR, CBER, FDA. The focus was on emerging innovations relevant to PRTs and potential alternatives to PRTs. The workshop concluded with remarks on insights for future research and development in this area for blood and blood product safety from infectious agents. A brief introduction of each session by the session moderator followed by a summary of the speaker presentation as submitted by the moderator and speaker are reported here.

Molecular monitoring of the diversity of human pathogenic malaria species in blood donations on Bioko Island, Equatorial Guinea

BackgroundMalaria can be transmitted by blood transfusion from human to human and it is responsible for the majority of transfusion-transmitted infectious diseases worldwide. In sub-Saharan Africa, it had been estimated that almost a quarter of blood donations contain malaria parasites. Since rapid diagnostic tests and thick blood smear microscopy lack sensitivity for low density parasitaemia, particularly in asymptomatic adults, the most reliable method to assess the problem of transfusion-transmitted malaria are nucleic acid-based molecular approaches such as quantitative polymerase chain reaction. The study was undertaken to determine the prevalence of sub-microscopic malaria parasite infection among blood donors in Malabo, Equatorial Guinea.MethodsBetween July and August 2017, a total of 200 individual blood samples from blood donors at the Malabo Blood Bank were collected and screened by rapid diagnostic tests and thick blood smear microscopy. Retrospectively, the same samples were analysed for the presence of undetected, low-density malaria parasites using quantitative polymerase chain reaction.ResultsIn comparison to 6.5% (13/200) by rapid diagnostic test and 2.0% (4/200) by microscopy, the proportion of Plasmodium falciparum positive blood donations analysed by quantitative polymerase chain reaction was significantly higher (26%, 52/200). Densities of P. falciparum positive blood donations were ranging from 0.06 to 3707.0 parasites/µL with 79.6% below 100 parasites/µL and therefore not detectable by non-molecular malaria diagnostic tests. qPCR based species identification revealed that P. falciparum was the dominating species responsible for 88.1% (52/59) of positive blood donations, followed by Plasmodium malariae (15.3%, 9/59) and Plasmodium ovale (3.4%, 2/59).ConclusionsThis study confirms that in malaria endemic settings, sub-patent malaria infections among blood donors are prevalent. In blood collected from healthy donors living in Malabo, P. falciparum, P. malariae and P. ovale parasites were identified. Currently widely used malaria diagnostic tools have missed more than 75% of P. falciparum containing blood donations, demonstrating the value of quantitative polymerase chain reaction to reliably detect low density P. falciparum infections. Since the availability of molecular diagnostic methods in malaria endemic countries is still limited, the blood recipients living in malaria endemic countries should be treated following WHO recommendations.

Results of clinical application of pathogen-reduced red blood cell suspension in children with oncological and hematological diseases

The problem of blood-borne infections remains relevant in transfusion medicine. Pathogen reduction technologies (PRT) provide a preventive approach to a wide range of transfusion-transmitted infectious diseases. To date, PRT widely used for a number of blood components, however, the use of these technologies for the treatment of erythrocyte-containing components has not been studied. Objective: to conduct a comparative analysis of the clinical efficacy of transfusions of pathogen-reduced and gamma-irradiated erythrocyte suspension in pediatric patients with various oncological and hematological diseases. Seventy transfusions of red blood cell suspensions (RBC-S) (35 transfusions of pathogen-reduced RBC-S and 35 transfusions of gammairradiated RBC-S) in pediatric patients with oncological and hematological diseases were analized. Clinical efficacy parameters such as the hemoglobin and the hematocrit increment after transfusion, the interval between transfusions, the frequency and severity of transfusion reactions were estimated. We also evaluated the correlation between the hemoglobin and the hematocrit increment with age, patient’s body weight, the hemoglobin concentration and patient's hematocrit before transfusion, the volume of transfusion, the hemoglobin dose and the adjusted hemoglobin dose received for transfusion. We found that the clinical efficacy and safety of RBC-Ss of the compared groups did not differ: the hematocrit and the hemoglobin increment, the frequency and severity of transfusion reactions, and the interval between transfusions were comparable between groups. There was no evidence of immune elimination and allo-sensibilization caused by pathogen-reduced RBC-S. In the group of patients receiving pathogen-reduced RBC-S, a correlation was found between the increase in the hemoglobin and hematocrit values with some of the EV indices. According to our data, the spectrum of efficiency and safety indicators of pathogen-reduced RBC-S is no worse than that of gamma-irradiated RBC-S, provided that RBC-S is used for 14 days of storage.