Frequent detection but lack of infectivity of SARS-CoV-2 RNA in pre-symptomatic, infected blood donor plasma

Clinical management of a patient following a granulocyte transfusion from a donor positive for COVID-19

Granulocyte transfusions are indicated for patients with severe neutropenia and evidence of bacterial or fungal infection who are unresponsive to standard antimicrobial therapy. With a limited expiration time of 24 hours after collection, granulocytes are often transfused before results of infectious-disease screening tests are available, and before a transfusion service can perform a risk assessment if postdonation information is provided after the collection. The case we describe herein demonstrates a clinical scenario meeting indications for granulocyte transfusion, coupled with the clinical management undertaken after the granulocyte donor disclosed a positive result for a COVID-19 self-test taken 1 day after donation. In this case, the patient did not develop new COVID-19 symptoms and tested negative for COVID-19 after transfusion of the implicated unit. These findings add to the body of evidence in the literature that COVID-19 is not transmitted via blood transfusion.

In situ and in vitro evaluation of two antiseptics for blood bank based on chlorhexidine gluconate/isopropyl alcohol and povidone-iodine

BACKGROUND

Poor disinfection is the main cause of blood contamination, so its elimination is key to limiting the entry of bacteria into the collection system. With the advancement of antiseptic technology, antiseptics with sterile, disposable applicators are now available.

AIM

To evaluate in situ two antiseptics (with and without applicators) for blood banks and to demonstrate in vitro antiseptic activity on bacterial biofilms of importance in transfusion medicine.

METHODS

Antiseptic A (2% sterile solution of chlorhexidine gluconate/70% isopropyl alcohol provided with applicator) and bulk antiseptic B (10% povidone-iodine) were evaluated. The deferred blood donor arms were subjected to disinfection with antiseptics A and B and the contralateral arms were cultured to determine the baseline bacterial load (control). Antiseptic activity was assessed by ANOVA and logaritmic reduction values (LRV) and percentage reduction values (PRV) were calculated. Finally, the in vitro activity of antiseptic A was analyzed by confocal laser scanning microscopy (CLSM) on biofilm models.

RESULTS

Prior to disinfection tests, commensal and clinically important bacteria were identified; antiseptic A showed post-disinfection bacterial growth rates of zero compared to controls (p < 0.0001). The frequency of bacterial growth with antiseptic B was 74%. A significant difference was identified between both antiseptics, where antiseptic A showed higher activity (p < 0.5468). LRV and PRV were 0.6-2.5/100% and 0.3-1.7/66.7-99.7% for antiseptics A and B, respectively. Through CLSM, disinfectant A (without applicator) showed lower in vitro antiseptic activity on the tested biofilms at the exposure times recommended by the manufacturer.

CONCLUSIONS

Sterile solution of chlorhexidine gluconate/isopropyl alcohol with applicator showed advantages disinfection in deferred blood donors over povidone-iodine.

Antibody and B Cell Responses to SARS-CoV-2 Infection and Vaccination: The End of the Beginning

As the COVID-19 pandemic has evolved during the past years, interactions between human immune systems, rapidly mutating and selected SARS-CoV-2 viral variants, and effective vaccines have complicated the landscape of individual immunological histories. Here, we review some key findings for antibody and B cell-mediated immunity, including responses to the highly mutated omicron variants; immunological imprinting and other impacts of successive viral antigenic variant exposures on antibody and B cell memory; responses in secondary lymphoid and mucosal tissues and non-neutralizing antibody-mediated immunity; responses in populations vulnerable to severe disease such as those with cancer, immunodeficiencies, and other comorbidities, as well as populations showing apparent resistance to severe disease such as many African populations; and evidence of antibody involvement in postacute sequelae of infection or long COVID. Despite the initial phase of the pandemic ending, human populations will continue to face challenges presented by this unpredictable virus.

Risk of transfusion-transmitted infection with severe acute respiratory syndrome coronavirus 2 from blood donors in Japan

BACKGROUND

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) essentially affects respiratory organs and tissues. SARS-CoV-2 RNAemia is often associated with more severe cases of coronavirus disease 2019 (COVID-19) compared to cases without RNAemia. To determine the impact of the pandemic on transfusion medicine, particularly transfusion-related infection, we examined the frequency of blood donation with RNAemia, the viral RNA (vRNA) concentration, and any possibility of transfusion-transmitted infection (TTI) among transfusion recipients.

STUDY DESIGN AND METHODS

vRNA was examined in plasma/serum samples from 496 of 513 blood donors who reported having been infected with SARS-CoV-2 within 2 weeks of donation among a total of ca. 9.9 million blood donations in Japan between January 15, 2020, and December 31, 2021. The clinical course of patients transfused with the blood component containing vRNA was also examined.

RESULTS

vRNA was detected in 23 of 496 samples. The median period from blood donation to COVID-19 onset was 1 day in 16 RNAemia-positive donors. Most samples had vRNA concentrations below the limit of quantification. Three patients were transfused with either a packed red blood cell or platelet concentrate that tested positive for vRNA, showing no COVID-19 symptoms and testing negative for vRNA in post-transfusion blood.

CONCLUSION

The rate of RNAemia was 4.6% among blood donors who were found to be infected with SARS-CoV-2 shortly after donation, and vRNA concentrations in their donated blood were extremely low. There was no evidence of TTI in the recipients transfused with RNAemia-positive blood components. TTI risk in SARS-CoV-2 is negligible.

Investigating Blood Donors With Postdonation Respiratory Tract Symptoms During the Wild-Type, Delta, and Omicron Waves of the Coronavirus Disease 2019 Pandemic in England

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been shown to be detectable in blood from infected individuals. Though RNAemia frequencies are typically low, the presence of potentially infectious virus potentially poses a transmission risk during blood transfusion.

Methods

Archived plasma samples were collected from blood donors who later reported possible SARS-CoV-2 infection with the wild-type strain, Delta variant, or Omicron variant. This was based on either symptom onset or a positive test within 2 weeks from their donation. Donations were tested for SARS-CoV-2 RNA, and information on symptoms and testing results were gathered during postdonation interview.

Results

Of 518 archived plasma samples tested, 19 (3.7%) were found to have detectable levels of SARS-CoV-2 RNA. SARS-CoV-2 RNA was detected in donors who donated during the Delta (10/141 [7.1%]) and Omicron (9/162 [5.6%]) waves. SARS-CoV-2 RNA was not detected in donors who donated during the wild-type wave (0/215). Seventeen of 19 RNAemic donors reported symptom onset or a positive test within 2 days of donating. SARS-CoV-2 RNA was detected in asymptomatic or presymptomatic blood donors.

Conclusions

Despite RNAemia being correlated with SARS-CoV-2 disease severity, RNAemia was detected in asymptomatic or presymptomatic blood donors.

Current advances in 2022: A critical review of selected topics by the Association for the Advancement of Blood and Biotherapies (AABB) Clinical Transfusion Medicine Committee

BACKGROUND

The Association for the Advancement of Blood and Biotherapies Clinical Transfusion Medicine Committee (CTMC) composes a summary of new and important advances in transfusion medicine (TM) on an annual basis. Since 2018, this has been assembled into a manuscript and published in Transfusion.

STUDY DESIGN AND METHODS

CTMC members selected original manuscripts relevant to TM that were published electronically and/or in print during calendar year 2022. Papers were selected based on perceived importance and/or originality. References for selected papers were made available to CTMC members to provide feedback. Members were also encouraged to identify papers that may have been omitted initially. They then worked in groups of two to three to write a summary for each new publication within their broader topic. Each topic summary was then reviewed and edited by two separate committee members. The final manuscript was assembled by the first and senior authors. While this review is extensive, it is not a systematic review and some publications considered important by readers may have been excluded.

RESULTS

For calendar year 2022, summaries of key publications were assembled for the following broader topics within TM: blood component therapy; infectious diseases, blood donor testing, and collections; patient blood management; immunohematology and genomics; hemostasis; hemoglobinopathies; apheresis and cell therapy; pediatrics; and health care disparities, diversity, equity, and inclusion.

DISCUSSION

This Committee Report reviews and summarizes important publications and advances in TM published during calendar year 2022, and maybe a useful educational tool.

Emerging Pathogen Threats in Transfusion Medicine: Improving Safety and Confidence with Pathogen Reduction Technologies

Emerging infectious disease threats are becoming more frequent due to various social, political, and geographical pressures, including increased human-animal contact, global trade, transportation, and changing climate conditions. Since blood products for transfusion are derived from donated blood from the general population, emerging agents spread by blood contact or the transfusion of blood products are also a potential risk. Blood transfusions are essential in treating patients with anemia, blood loss, and other medical conditions. However, these lifesaving procedures can contribute to infectious disease transmission, particularly to vulnerable populations. New methods have been implemented on a global basis for the prevention of transfusion transmissions via plasma, platelets, and whole blood products. Implementing proactive pathogen reduction methods may reduce the likelihood of disease transmission via blood transfusions, even for newly emerging agents whose transmissibility and susceptibility are still being evaluated as they emerge. In this review, we consider the Mirasol PRT system for blood safety, which is based on a photochemical method involving riboflavin and UV light. We provide examples of how emerging threats, such as Ebola, SARS-CoV-2, hepatitis E, mpox and other agents, have been evaluated in real time regarding effectiveness of this method in reducing the likelihood of disease transmission via transfusions.

Prevalence of SARS-CoV-2 Viremia in Presymptomatic Blood Donors in the Delta and Omicron Variant Eras

Presymptomatic plasma samples from 1596 donors reporting coronavirus disease 2019 infection or symptoms after blood donation were tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and anti-S and anti-N antibodies. Prior infection and vaccination both protected from developing SARS-CoV-2 RNAemia and from symptomatic infection. RNAemia rates did not differ in the Delta and Omicron variant eras.

How do we forecast tomorrow's transfusion: Infectious safety?

Continuous improvement has led to a very high degree of microbial safety of transfusion. Four issues are likely to impact the future of this safety. There will be further advances in the efficacy and efficiency of donation testing and pathogen reduction, increasing safety and hopefully eliminating unnecessary procedures. While system failures have been essentially eliminated, there will be ongoing, unpredictable issues that are inevitable. Emerging infections are likely the greatest concern and will continue, although advances in science and technology will permit increasingly rapid responses to outbreaks. Finally, the practice of transfusion may eventually impact safety as usage of blood is reduced and perhaps as alternatives to conventional blood components are developed.

Viral Metagenomics for Identification of Emerging Viruses in Transfusion Medicine

Viral metagenomics has revolutionized our understanding for identification of unknown or poorly characterized viruses. For that reason, metagenomic studies gave been largely applied for virus discovery in a wide variety of clinical samples, including blood specimens. The emerging blood-transmitted virus infections represent important problem for public health, and the emergence of HIV in the 1980s is an example for the vulnerability of Blood Donation systems to such infections. When viral metagenomics is applied to blood samples, it can give a complete overview of the viral nucleic acid abundance, also named "blood virome". Detailed characterization of the blood virome of healthy donors could identify unknown (emerging) viral genomes that might be assumed as hypothetic transfusion threats. However, it is impossible only by application of viral metagenomics to assign that one viral agent could impact blood transfusion. That said, this is a complex issue and will depend on the ability of the infectious agent to cause clinically important infection in blood recipients, the viral stability in blood derivatives and the presence of infectious viruses in blood, making possible its transmission by transfusion. This brief review summarizes information regarding the blood donor virome and some important challenges for use of viral metagenomics in hemotherapy for identification of transfusion-transmitted viruses.