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1.
Cell & Tissue Banking ; 09:09, 2022.
Article in English | MEDLINE | ID: covidwho-2158085

ABSTRACT

Given the possibility for disease transmission, this study was performed to determine whether there is detectable SARS-CoV-2 viral RNA in the blood of deceased tissue donors. A retrospective analysis of blood samples from eligible deceased tissue donors from Oct 2019 through June 2020 was performed. Plasma aliquots were initially tested with a SARS-CoV-2 NAT Assay;positive samples were further tested using an alternate NAT and an antibody assay. The proportion of donors with confirmed RNAemia and 95% confidence intervals were computed. Of donor samples collected in 2019, 894 yielded valid results, with 6 initially positive, none of which confirmed positive by alternate NAT. Of donor samples collected in 2020, 2562 yielded valid initial NAT results, with 21 (0.8%) initially positive. Among those, 3 were confirmed by alternate NAT, 17 were not confirmed, and 1 had an invalid alternate NAT result. The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1000, and it is unknown whether this RNAemia reflects the presence of infectious virus. Given these results, the risk of transmission through tissue is thought likely to be low.

2.
Open Forum Infectious Diseases ; 8(SUPPL 1):S288, 2021.
Article in English | EMBASE | ID: covidwho-1746622

ABSTRACT

Background. Tissue donors are evaluated for communicable disease in order to minimize the risk of transmission to recipients. Although there are data suggesting SARS-CoV-2 viremia across a wide spectrum of illness, prevalence in deceased tissue donors and the potential for transplant transmission are unknown. Methods. Eight tissue banks participated in a retrospective analysis of samples from eligible deceased tissue donors from Oct 2019 through June 2020, one participant in Canada and the remainder located in the United States. All four Census regions of the continental US and all major racial-ethnic groups were represented. EDTA or sodium citrate plasma aliquots were tested in singlicate with the Research Use Only Procleix SARS-CoV-2 Assay on the Procleix Panther System, which uses transcription-mediated nucleic acid amplification (TMA) technology for detection of the SARSCoV-2 RNA. Plasma (or if unavailable, serum) aliquots were sent to Grifols for an alternate SARS-CoV-2 nucleic acid amplification (NAT) test to verify reactivity and also sent for antibody testing using the emergency use authorization Ortho VITROS Immunodiagnostic Products Anti-SARS-CoV-2 Total test. The VITROS assay uses immunometric technology for qualitative measurement of total antibody (IgG, IgA and IgM) to SARS-CoV-2. The proportion of donors with confirmed RNAemia (i.e., presence of SARS-CoV-2 RNA in plasma or serum) and 95% confidence intervals were computed. Results. Of 3,455 donor samples with valid final results, 26 (0.76%) were initially positive for SARS-CoV-2 RNA;of these, 3 were confirmed by alternate NAT. Of donor samples collected in 2019 0.00% (95% CI: 0.00%,0.43%) were confirmed RNAemic, while of those collected in 2020, 0.12% (0.04%,0.34%) were confirmed RNAemic. One of 26 initial positive, and none of the three samples confirmed by alternate NAT, tested positive for anti-SARS-CoV-2 Spike antibodies by serology. Infectivity studies are pending on one sample with sufficient available volume. Conclusion. The rate of SARS-CoV-2 RNAemia in deceased tissue donors is approximately 1 per 1,000, and it is unknown whether this RNAemia reflects the presence of infectious virus. Given these results, the risk of transmission through tissue is most likely to be low.

5.
2021 CHI Conference on Human Factors in Computing Systems: Making Waves, Combining Strengths, CHI EA 2021 ; 2021.
Article in English | Scopus | ID: covidwho-1238582

ABSTRACT

The COVID19 pandemic has unfolded alongside a concurrent g€infodemic' - defined by the World Health Organization as an overabundance of information, some accurate, some not, that occurs during an epidemic. Key to managing this is not only identifying, countering and debunking misinformation but also providing unbiased and factually correct information and signposting people towards it. However, during COVID19, the g€truth' has not always been clear. It has not always been easy to prepare public health messaging that is consistent, easily understood or practical for everyone to apply. This presents unique challenges, to which social media platforms need to be part of the solution. One such solution can be found on www.reddit.com where, in January 2020, a group of research scientists, students, academics and medics came together to create and moderate forums in which the pandemic can be discussed and questions about it answered. These forums provide case studies of how information can be generated, misinformation corrected and disinformation debunked on subreddits with, combined, more than 3 million subscribers. © 2021 Owner/Author.

6.
Transfusion ; 60(SUPPL 5):276A-277A, 2020.
Article in English | EMBASE | ID: covidwho-1044277

ABSTRACT

Background/Case Studies: Blood donor based serosurveillance is a convenient and cost-effective strategy to monitor the extent of the COVID-19 pandemic and allows the detection of asymptomatic and recovered cases. The RESPONSE (REDS-IV-P Epidemiology, Surveillance and Preparedness of the Novel SARS-CoV-2 Epidemic) study conducted monthly cross-sectional serosurveys of 1000 routinely obtained donor samples in 6 metropolitan regions (see table). Study Design/Methods: Samples were captured monthly from March or April through June 2020. Siteswere selected based on reports of epidemic activity or as low prevalence control regions. Donations from COVID- 19 convalescent plasma donors were excluded. Coded samples, with routinely collected demographic data and zip code of residence, were tested for SARS-CoV-2 antibodies using the Ortho VITROS anti-SARS-CoV-2 S1 Total Ig (data reported below) with planned confirmation of reactivity on Roche Elecsys® NC Anti-SARS-CoV-2 and a pseudovirus-based neutralization assay. Results/Findings: Table 1 shows donor seroreactivity with 95% CI. For all sites, seroreactivity was <1.0% (range 0.1%-0.9%) at the beginning of the surveillance period. Donor seroreactivity in New York City (NYC) was about 10-fold higher in April through June as compared to March and was much higher than in other locations. There were modest increases in seroreactivity over the study timeframe for all other sites. Conclusions: Modest increases in seroreactivity from baseline were found in all sites, with the largest increase in NYC. SARS-CoV-2 antibody testing of routinely obtained blood donor samples allows for detection of asymptomatic and recovered COVID-19 cases and enables future estimation of infection incidence by geographic and other demographic parameters. This approach will be used in a significantly expanded CDC National serosurveillance study involving all 50 states over 18 months.

7.
Transfusion ; 60(SUPPL 5):278A, 2020.
Article in English | EMBASE | ID: covidwho-1043232

ABSTRACT

Background/Case Studies: The efficacy of COVID-19 convalescent plasma (CCP) to treat COVID-19 is hypothesized to be associated with the concentration of neutralizing antibodies (nAb) to SARS-CoV-2. While high capacity, automated serologic assays to detect binding antibodies (bAb) have been developed, complex nAb assays are not easily adaptable to high-throughput testing. We sought to determine the effectiveness of using surrogate bAb signalto- cutoff ratio (S/CO) in predicting nAb titers using a pseudovirus reporter viral neutralization (RVPN) assay. Study Design/Methods: CCP donor serum collected by 3 large US blood collectors was tested with a bAb assay (Ortho Diagnostic VITROS® Anti-SARS-CoV-2 Total, CoV2T) and a nAb RVPN assay. Although EUA approved as a qualitative assay, CoV2T reports a semi-quantitative S/CO. The RVPN assay uses a pseudovirus construct with native S-protein and target cell lines overexpressing ACE2 receptor and TMPRSS2 protease. Serially diluted serum is mixed with SARS-CoV-2 pseudovirus to assess inhibition of viral entry in culture and reported as titers resulting in 50% neutralization of virus infectivity (NT50) by nonlinear regression analysis. CoV2T prediction effectiveness at several S/CO thresholds was evaluated for various RVPN nAb NT50 titers using receiver operating characteristic analysis. Results/Findings: 753 CCP donations were tested with median CoV2T S/CO of 71.2 (range 0.1-919) and median NT50 of 527.5 (range <40 to >10,240). The prevalence of CCP donors with NT50 over various target n-Ab titers were 86% >80, 76% >160, and 45% >640. Increasing CoV2T reactivity threshold reduces sensitivity to predict the target NT50 titer while specificity to identify those below nAb threshold increases for all targeted NT50s (Table 1). As the targeted NT50 is increased from >80 to >640, the positive predictive value falls dramatically while the negative predictive value increases, thus S/CO thresholds are less able to predict donors who have the target NT50 titer but more able to predict those donors who do not meet it. Conclusions: The selection of targeted nAb titer for clinical use will significantly impact availability of CCP for transfusion. Product release with CoV2T assay S/CO thresholds must balance the risk of releasing products below minimum target nAb titer and the cost of false negatives (CCP units below the threshold with adequate nAb titers). A two-step testing scheme may be optimal, with nAb testing performed on CoV2T reactive samples with S/CO values below the release threshold.

8.
Transfusion ; 60(SUPPL 5):276A, 2020.
Article in English | EMBASE | ID: covidwho-1041123

ABSTRACT

Background/Case Studies: SARS-CoV-2 RNA has been detected by PCR in plasma, serum or whole blood specimens from hospitalized patients in studies from multiple countries. For asymptomatic individuals, several reports have described detection of SARS-CoV-2 RNA in plasma in a small number of blood donors, whereas other reports showed no detection of SARS-CoV-2 RNA in whole blood, serum or plasma from asymptomatic individuals including blood donors. No cases of transfusion-transmission of SARS-CoV-2 (or other human coronaviruses) have been reported, nor has virus been isolated from blood samples by tissue culture. We tested residual volumes of donor plasma from mini-pools (MPs) used for routine nucleic acid testing (NAT) screening to determine the frequency of SARS-CoV-2 RNAemia in blood donors in six US metropolitan regions (New York, Seattle, San Francisco, Los Angeles, Boston, Minneapolis). Study Design/Methods: Blood donations collected from 7 March 2020 to 30 June 2020 were tested for SARS-CoV-2 RNA. Donations were tested in plasma MPs of 6 or 16 donations (MP16 format for five regions and MP6 format for Seattle), targeting 500 MPs per region per month, using the Grifols Procleix SARS-CoV-2 transcriptionmediated amplification (TMA) assay on the Procleix Panther system. The test has a 95% limit of detection (LOD) of 16.5 copies/mL (95% CI, 12.8 to 23.6 copies/mL) by probit analysis. A confirmed positive result was defined by the detection of viral RNA upon repeat testing using the same assay and an alternate target region TMA assay (Grifols SARS-CoV-2 confirmatory TMA assay) with comparable sensitivity. Positive MPs were further tested using the Ortho VITROS anti-SARS-CoV-2 Total Ig test to detect antibodies and diluted 4-fold and tested using the Procleix SARS-CoV-2 TMA assay to determine whether the viral load was close to the 95% LOD. Results/Findings: A total of 8,496 MPs16 and 1,998 MPs 6, corresponding to ∼147,000 blood donations, were tested for SARS-CoV-2 RNA. One confirmed positive MP16 sample from a March donation in San Francisco was identified (0.0007% [95% CI 0.000035-0.004%]). The MP was negative for antibody and nonreactive when diluted 4-fold, suggesting a viral load below 1,000 RNA copies/mL in the individual donation. Conclusions: Blood donation MP-NAT indicated that SARS-CoV-2 RNAemia is rare, and when detected the RNA was at low concentration. Although future studies to determine the infectivity of RNA-positive plasma are warranted and in progress, these findings are reassuring with respect to transfusion safety and support current recommendations from WHO and regulatory agencies to not screen donors by NAT.

9.
F1000Research ; 9, 2020.
Article in English | EMBASE | ID: covidwho-891680

ABSTRACT

Background: Never before have clinical trials drawn as much public attention as those testing interventions for COVID-19. We aimed to describe the worldwide COVID-19 clinical research response and its evolution over the first 100 days of the pandemic. Methods: Descriptive analysis of planned, ongoing or completed trials by April 9, 2020 testing any intervention to treat or prevent COVID-19, systematically identified in trial registries, preprint servers, and literature databases. A survey was conducted of all trials to assess their recruitment status up to July 6, 2020. Results: Most of the 689 trials (overall target sample size 396,366) were small (median sample size 120;interquartile range [IQR] 60-300) but randomized (75.8%;n=522) and were often conducted in China (51.1%;n=352) or the USA (11%;n=76). 525 trials (76.2%) planned to include 155,571 hospitalized patients, and 25 (3.6%) planned to include 96,821 health-care workers. Treatments were evaluated in 607 trials (88.1%), frequently antivirals (n=144) or antimalarials (n=112);78 trials (11.3%) focused on prevention, including 14 vaccine trials. No trial investigated social distancing. Interventions tested in 11 trials with >5,000 participants were also tested in 169 smaller trials (median sample size 273;IQR 90-700). Hydroxychloroquine alone was investigated in 110 trials. While 414 trials (60.0%) expected completion in 2020, only 35 trials (4.1%;3,071 participants) were completed by July 6. Of 112 trials with detailed recruitment information, 55 had recruited <20% of the targeted sample;27 between 20-50%;and 30 over 50% (median 14.8% [IQR 2.0-62.0%]). Conclusions: The size and speed of the COVID-19 clinical trials agenda is unprecedented. However, most trials were small investigating a small fraction of treatment options. The feasibility of this research agenda is questionable, and many trials may end in futility, wasting research resources. Much better coordination is needed to respond to global health threats.

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