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1.
Transfusion ; 2021 Dec 22.
Article in English | MEDLINE | ID: covidwho-1583249

ABSTRACT

BACKGROUND: Several studies have described associations between ABO blood group and SARS-CoV-2 infection severity in hospitalized patients where group A individuals are over-represented and group O individuals may have a lower infection rate. In convalescent individuals, group B blood donors have higher neutralizing SARS-CoV-2 antibody titers. We analyzed whether there was any correlation of ABO Rh(D) blood group with SARS-CoV-2 infection and with neutralizing antibodies in Australian convalescent plasma (CP) donors. STUDY DESIGN AND METHODS: ABO Rh(D) distribution and demographics of CP donors (n = 765) were compared with the total blood donor panel (n = 488,028), plasmapheresis donors (n = 203,176) and whole blood donors (n = 282,437) from 2020. The presence of neutralizing antibodies in CP donors was measured using the Vero E6 cell microneutralization assay. RESULTS: The distribution of ABO group in CP donors compared to the total donor panel was not significantly different (p = .177). There were significantly more group AB donors in the plasmapheresis subset (p = .005) and group O individuals were over-represented in the whole blood donor subset (p < .0001). There was no significant difference in neutralizing antibody levels among CP donors with differing ABO blood groups (p = .872). CONCLUSION: ABO Rh(D) blood group distribution was not found to be significantly different between convalescent plasma donors and general blood donors in our large sample group. Inherent blood donor selection biases associated with clinical demand accounted for some differences within CP donors. The levels of SARS-CoV-2 neutralizing antibodies were also not significantly associated with ABO Rh(D) group.

2.
JAMA ; 326(17): 1690-1702, 2021 Nov 02.
Article in English | MEDLINE | ID: covidwho-1525402

ABSTRACT

Importance: The evidence for benefit of convalescent plasma for critically ill patients with COVID-19 is inconclusive. Objective: To determine whether convalescent plasma would improve outcomes for critically ill adults with COVID-19. Design, Setting, and Participants: The ongoing Randomized, Embedded, Multifactorial, Adaptive Platform Trial for Community-Acquired Pneumonia (REMAP-CAP) enrolled and randomized 4763 adults with suspected or confirmed COVID-19 between March 9, 2020, and January 18, 2021, within at least 1 domain; 2011 critically ill adults were randomized to open-label interventions in the immunoglobulin domain at 129 sites in 4 countries. Follow-up ended on April 19, 2021. Interventions: The immunoglobulin domain randomized participants to receive 2 units of high-titer, ABO-compatible convalescent plasma (total volume of 550 mL ± 150 mL) within 48 hours of randomization (n = 1084) or no convalescent plasma (n = 916). Main Outcomes and Measures: The primary ordinal end point was organ support-free days (days alive and free of intensive care unit-based organ support) up to day 21 (range, -1 to 21 days; patients who died were assigned -1 day). The primary analysis was an adjusted bayesian cumulative logistic model. Superiority was defined as the posterior probability of an odds ratio (OR) greater than 1 (threshold for trial conclusion of superiority >99%). Futility was defined as the posterior probability of an OR less than 1.2 (threshold for trial conclusion of futility >95%). An OR greater than 1 represented improved survival, more organ support-free days, or both. The prespecified secondary outcomes included in-hospital survival; 28-day survival; 90-day survival; respiratory support-free days; cardiovascular support-free days; progression to invasive mechanical ventilation, extracorporeal mechanical oxygenation, or death; intensive care unit length of stay; hospital length of stay; World Health Organization ordinal scale score at day 14; venous thromboembolic events at 90 days; and serious adverse events. Results: Among the 2011 participants who were randomized (median age, 61 [IQR, 52 to 70] years and 645/1998 [32.3%] women), 1990 (99%) completed the trial. The convalescent plasma intervention was stopped after the prespecified criterion for futility was met. The median number of organ support-free days was 0 (IQR, -1 to 16) in the convalescent plasma group and 3 (IQR, -1 to 16) in the no convalescent plasma group. The in-hospital mortality rate was 37.3% (401/1075) for the convalescent plasma group and 38.4% (347/904) for the no convalescent plasma group and the median number of days alive and free of organ support was 14 (IQR, 3 to 18) and 14 (IQR, 7 to 18), respectively. The median-adjusted OR was 0.97 (95% credible interval, 0.83 to 1.15) and the posterior probability of futility (OR <1.2) was 99.4% for the convalescent plasma group compared with the no convalescent plasma group. The treatment effects were consistent across the primary outcome and the 11 secondary outcomes. Serious adverse events were reported in 3.0% (32/1075) of participants in the convalescent plasma group and in 1.3% (12/905) of participants in the no convalescent plasma group. Conclusions and Relevance: Among critically ill adults with confirmed COVID-19, treatment with 2 units of high-titer, ABO-compatible convalescent plasma had a low likelihood of providing improvement in the number of organ support-free days. Trial Registration: ClinicalTrials.gov Identifier: NCT02735707.


Subject(s)
COVID-19/therapy , ABO Blood-Group System , Adult , Aged , Critical Illness/therapy , Female , Hospital Mortality , Humans , Immunization, Passive , Length of Stay , Logistic Models , Male , Middle Aged , Respiration, Artificial/statistics & numerical data , Treatment Failure , Vasoconstrictor Agents/therapeutic use
3.
PLoS Med ; 18(7): e1003656, 2021 07.
Article in English | MEDLINE | ID: covidwho-1298076

ABSTRACT

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) antibody neutralization response and its evasion by emerging viral variants and variant of concern (VOC) are unknown, but critical to understand reinfection risk and breakthrough infection following vaccination. Antibody immunoreactivity against SARS-CoV-2 antigens and Spike variants, inhibition of Spike-driven virus-cell fusion, and infectious SARS-CoV-2 neutralization were characterized in 807 serial samples from 233 reverse transcription polymerase chain reaction (RT-PCR)-confirmed Coronavirus Disease 2019 (COVID-19) individuals with detailed demographics and followed up to 7 months. A broad and sustained polyantigenic immunoreactivity against SARS-CoV-2 Spike, Membrane, and Nucleocapsid proteins, along with high viral neutralization, was associated with COVID-19 severity. A subgroup of "high responders" maintained high neutralizing responses over time, representing ideal convalescent plasma donors. Antibodies generated against SARS-CoV-2 during the first COVID-19 wave had reduced immunoreactivity and neutralization potency to emerging Spike variants and VOC. Accurate monitoring of SARS-CoV-2 antibody responses would be essential for selection of optimal responders and vaccine monitoring and design.


Subject(s)
Antibodies, Neutralizing/immunology , SARS-CoV-2/pathogenicity , Adult , Antibodies, Viral/immunology , Female , Humans , Male , Middle Aged , Nucleocapsid Proteins/immunology , SARS-CoV-2/immunology
4.
Med J Aust ; 214(4): 179-185, 2021 03.
Article in English | MEDLINE | ID: covidwho-1067930

ABSTRACT

OBJECTIVES: To estimate SARS-CoV-2-specific antibody seroprevalence after the first epidemic wave of coronavirus disease 2019 (COVID-19) in Sydney. SETTING, PARTICIPANTS: People of any age who had provided blood for testing at selected diagnostic pathology services (general pathology); pregnant women aged 20-39 years who had received routine antenatal screening; and Australian Red Cross Lifeblood plasmapheresis donors aged 20-69 years. DESIGN: Cross-sectional study; testing of de-identified residual blood specimens collected during 20 April - 2 June 2020. MAIN OUTCOME MEASURE: Estimated proportions of people seropositive for anti-SARS-CoV-2-specific IgG, adjusted for test sensitivity and specificity. RESULTS: Thirty-eight of 5339 specimens were IgG-positive (general pathology, 19 of 3231; antenatal screening, 7 of 560; plasmapheresis donors, 12 of 1548); there were no clear patterns by age group, sex, or location of residence. Adjusted estimated seroprevalence among people who had had general pathology blood tests (all ages) was 0.15% (95% credible interval [CrI], 0.04-0.41%), and 0.29% (95% CrI, 0.04-0.75%) for plasmapheresis donors (20-69 years). Among 20-39-year-old people, the age group common to all three collection groups, adjusted estimated seroprevalence was 0.24% (95% CrI, 0.04-0.80%) for the general pathology group, 0.79% (95% CrI, 0.04-1.88%) for the antenatal screening group, and 0.69% (95% CrI, 0.04-1.59%) for plasmapheresis donors. CONCLUSIONS: Estimated SARS-CoV-2 seroprevalence was below 1%, indicating that community transmission was low during the first COVID-19 epidemic wave in Sydney. These findings suggest that early control of the spread of COVID-19 was successful, but efforts to reduce further transmission remain important.


Subject(s)
Antibodies, Viral/blood , COVID-19/epidemiology , COVID-19/virology , Pandemics , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Australia/epidemiology , Blood Donors , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Immunoglobulin G/blood , Infant , Infant, Newborn , Male , Middle Aged , Pregnancy , Seroepidemiologic Studies , Young Adult
5.
Viruses ; 13(2)2021 02 04.
Article in English | MEDLINE | ID: covidwho-1063429

ABSTRACT

Serological testing for SARS-CoV-2-specific antibodies provides important research and diagnostic information relating to COVID-19 prevalence, incidence and host immune response. A greater understanding of the relationship between functionally neutralising antibodies detected using microneutralisation assays and binding antibodies detected using scalable enzyme immunoassays (EIA) is needed in order to address protective immunity post-infection or vaccination, and assess EIA suitability as a surrogate test for screening of convalescent plasma donors. We assessed whether neutralising antibody titres correlated with signal cut-off ratios in five commercially available EIAs, and one in-house assay based on expressed spike protein targets. Sera from recovered patients or convalescent plasma donors who reported laboratory-confirmed SARS-CoV-2 infection (n = 200), and negative control sera collected prior to the COVID-19 pandemic (n = 100), were assessed in parallel. Performance was assessed by calculating EIA sensitivity and specificity with reference to microneutralisation. Neutralising antibodies were detected in 166 (83%) samples. Compared with this, the most sensitive EIAs were the Cobas Elecsys Anti-SARS-CoV-2 (98%) and Vitros Immunodiagnostic Anti-SARS-CoV-2 (100%), which detect total antibody targeting the N and S1 antigens, respectively. The assay with the best quantitative relationship with microneutralisation was the Euroimmun IgG. These results suggest the marker used (total Ab vs. IgG vs. IgA) and the target antigen are important determinants of assay performance. The strong correlation between microneutralisation and some commercially available assays demonstrates their potential for clinical and research use in assessing protection following infection or vaccination, and use as a surrogate test to assess donor suitability for convalescent plasma donation.


Subject(s)
Antibodies, Viral/blood , COVID-19 Serological Testing , COVID-19/immunology , Enzyme-Linked Immunosorbent Assay , Neutralization Tests , SARS-CoV-2/immunology , COVID-19/diagnosis , Humans , Immunoglobulin A/blood , Immunoglobulin G/blood , ROC Curve , Sensitivity and Specificity
6.
Transfus Med ; 31(3): 176-185, 2021 Jun.
Article in English | MEDLINE | ID: covidwho-999165

ABSTRACT

OBJECTIVES: To determine the motivators and barriers to COVID-19 convalescent plasma donation by those in the United Kingdom who have been diagnosed with or who have had symptoms of SARS-CoV-2 (COVID-19) but who have not donated. BACKGROUND: Convalescent plasma from people recovered from COVID-19 with sufficient antibody titres is a potential option for the treatment and prevention of COVID-19. However, to date, recruiting and retaining COVID-19 convalescent plasma donors has been challenging. Understanding why those eligible to donate COVID-19 convalescent plasma have not donated is critical to developing recruitment campaigns. METHODS/MATERIALS: A total of 419 UK residents who indicated that they had been infected with COVID-19 and who lived within 50 km of sites collecting COVID-19 convalescent plasma completed an online survey between 25th June and 5th July 2020. Respondents completed items assessing their awareness of convalescent plasma, motivations and barriers to donation and intention to donate COVID-19 convalescent plasma. RESULTS: Awareness of COVID-19 convalescent plasma was low. Exploratory factor analysis identified six motivations and seven barriers to donating. A stronger sense of altruism through adversity and moral and civic duty were positively related to intention to donate, whereas generic donation fears was negatively related. CONCLUSIONS: Once potential donors are aware of convalescent plasma, interventions should focus on the gratitude and reciprocity that those eligible to donate feel, along with a focus on (potentially) helping family and norms of what people ought to do. Fears associated with donation should not be neglected, and strategies that have been successfully used tor recruit whole-blood donors should be adapted and deployed to recruit COVID-19 convalescent plasma donors.


Subject(s)
Blood Donors/psychology , COVID-19/therapy , Motivation , SARS-CoV-2 , Surveys and Questionnaires , Adolescent , Adult , Aged , Altruism , Awareness , Blood Donors/statistics & numerical data , Donor Selection/methods , Fear , Female , Humans , Immunization, Passive , Male , Middle Aged , Plasma , United Kingdom , Young Adult
7.
Vox Sang ; 116(2): 155-166, 2021 Feb.
Article in English | MEDLINE | ID: covidwho-787954

ABSTRACT

BACKGROUND AND OBJECTIVE: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is a novel coronavirus, first identified in China at the end of 2019 and has now caused a worldwide pandemic. In this review, we provide an overview of the implications of SARS-CoV-2 for blood safety and sufficiency. MATERIAL AND METHOD: We searched the PubMed database, the preprint sites bioRxiv and medRxiv, the websites of the World Health Organization, European Centre for Disease Prevention and Control, the US Communicable Diseases Center and monitored ProMed updates. RESULTS: An estimated 15%-46% of SARS-CoV-2 infections are asymptomatic. The reported mean incubation period is 3 to 7 days with a range of 1-14 days. The blood phase of SARS-CoV-2 appears to be brief and low level, with RNAaemia detectable in only a small proportion of patients, typically associated with more severe disease and not demonstrated to be infectious virus. An asymptomatic blood phase has not been demonstrated. Given these characteristics of SARS-CoV-2 infection and the absence of reported transfusion transmission (TT), the TT risk is currently theoretical. To mitigate any potential TT risk, but more importantly to prevent respiratory transmission in donor centres, blood centres can implement donor deferral policies based on travel, disease status or potential risk of exposure. CONCLUSION: The TT risk of SARS-CoV-2 appears to be low. The biggest risk to blood services in the current COVID-19 pandemic is to maintain the sufficiency of the blood supply while minimizing respiratory transmission of SARS-CoV-19 to donors and staff while donating blood.


Subject(s)
Blood Safety , COVID-19/blood , COVID-19/prevention & control , COVID-19/virology , Transfusion Reaction/prevention & control , Blood Transfusion , Geography , Humans , RNA, Viral/analysis , Risk Assessment , SARS-CoV-2 , Safety Management , World Health Organization
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