ABSTRACT
Introduction: Rapid antigen detection tests (RDT) are suitable for large-scale testing for SARS-CoV-2 among the population and recent studies have shown that self-testing with RDT in the general population is feasible and yields acceptable sensitivities with high specificity. We aimed to determine the accuracy of two different RDT, with two different sample collection methods for one of the RDT among healthcare workers (HCW). Secondary objectives were to determine the accuracy of RDT using a viral load cut-off as proxy of infectiousness and to identify predictors for a false negative RDT. Methods: Centers that participated were secondary care hospitals, academic teaching hospitals, and long-term care facilities. All HCW that met inclusion criteria were asked to perform a RDT self-test next to a regular SARS-CoV-2 nucleic acid amplification test (NAAT). Three study groups were created. Study group 1; Veritor System, Becton Dickinson, Franklin Lakes, USA (BD-RDT) with combined oropharyngeal - mid-turbinate nasal sampling, group 2; BD-RDT with mid-turbinate nasal sampling only and group 3; SD Biosensor SARS-CoV-2 Rapid Antigen Test, Roche, Basel, Switzerland (Roche-RDT) with combined oropharyngeal - mid-turbinate nasal sampling. RDT accuracy was calculated using NAAT as reference standard. For samples processed in the cobas(R) 6800/8800 platform (Roche Diagnostics, Basel, Switzerland), established cycle threshold values (Ct-values) could be converted into viral loads. A viral load cut-off of [≥]5.2 log10 SARS-CoV-2 E gene copies/ml was used as proxy of infectiousness. Logistic regression analysis was performed to identify predictors for a false negative RDT. Results: In total, 7,196 HCW were included. Calculated sensitivities were 61.5% (95%CI 56.6%-66.3%), 50.3% (95%CI 42.8%-57.7%) and 74.2% (95%CI 66.4%-80.9%) for study groups 1, 2 and 3, respectively. After application of a viral load cut-off as a proxy for infectiousness for samples processed in the cobas(R) 6800/8800 platform sensitivities increased to 82.2% (95%CI 76.6-86.9%), 61.9% (95%CI 48.8%-73.9%) and 90.2% (95%CI 76.9%-97.3%) for group 1, group 2 and group 3, respectively. Multivariable regression analysis showed that use of Roche-RDT (p <0.01), combined oropharyngeal - mid-turbinate nasal sampling (p <0.05) and the presence of COVID-19 like symptoms at the time of testing (p <0.01) significantly reduced the likeliness of a false-negative RDT result. Conclusion: SARS-CoV-2 RDT has proven able to identify infectious individuals, especially when upper respiratory specimen is collected through combined oropharyngeal - mid-turbinate sampling. Reliability of self-testing with RDT among HCW seems to depend on the type of RDT, the sampling method and the presence of COVID-19 like symptoms at the time of testing.
Subject(s)
COVID-19ABSTRACT
Background There is an urgent need for fair and equitable access to safe and effective vaccines to end the COVID-19 pandemic. Shortages in reagents and vaccines are a major challenge, as well as limited knowledge on dose response relationship with mRNA COVID-19 vaccines. We explored intradermal fractional dose administration of a mRNA SARS-CoV-2/COVID-19 vaccine as a potential dose-sparing strategy. Methods We conducted a proof-of-concept, dose-escalation, open-label, randomised-controlled vaccine trial (IDSCOVA) in healthy adults aged 18-30 years. To test initial safety, ten participants received 10 g mRNA-1273 vaccine through intradermal injection at day 1 and 29. Following a favourable safety review, thirty participants were 1:1 randomised to receive 20 g mRNA-1273 either intradermally or intramuscularly. The primary endpoint was tolerability and safety. The secondary endpoint was seroconversion and specific IgG concentration against SARS-CoV-2 spike S1 and Receptor Binding Domain (RBD) after the second dose at day 43. We compared results to two historical cohorts of non-hospitalised COVID-19 patients and vaccinated individuals. Findings Thirty-eight of forty included participants (median age 25 years) completed the study. There were no serious adverse events. Self-reported local adverse reactions after intradermal delivery were mild, both in the 10 g and the 20 g group. In the higher dose group, systemic adverse reactions were more common, but still well tolerated. All 38 participants mounted substantially higher IgG-anti-S1 and IgG-anti-RBD concentrations at day 43 than COVID-19 controls. At day 43, anti-S1 (95% CI) was 1,696 (1,309-2,198) BAU/mL for the 10 g intradermal group, 1,406 (953.5-2,074) BAU/mL for the 20 g intramuscular group and 2,057 (1,421-2,975) BAU/mL for the 20 g intradermal group. Anti-S1 was 107.2 (63-182.2) BAU/mL for the convalescent plasma control group and 1,558 (547.8-4,433) BAU/mL for the individuals vaccinated with 100 g mRNA-1273. Interpretation Intradermal administration of 10 g and 20 g mRNA-1273 vaccine was well tolerated and safe, and resulted in a robust antibody response. Intradermal vaccination has the potential to be deployed for vaccine dose-sparing.
Subject(s)
COVID-19ABSTRACT
Background: There is an urgent need for fair and equitable access to safe and effective vaccines to end the COVID-19 pandemic. Shortages in reagents and vaccines are a major challenge, as well as limited knowledge on dose response relationship with mRNA COVID-19 vaccines. We explored intradermal fractional dose administration of a mRNA SARS-CoV-2/COVID-19 vaccine as a potential dose-sparing strategy. Methods: We conducted a proof-of-concept, dose-escalation, open-label, randomised-controlled vaccine trial (IDSCOVA) in healthy adults aged 18-30 years. To test initial safety, ten participants received 10 µg mRNA-1273 vaccine through intradermal injection at day 1 and 29. Following a favourable safety review, thirty participants were 1:1 randomised to receive 20 µg mRNA-1273 either intradermally or intramuscularly. The primary endpoint was tolerability and safety. The secondary endpoint was seroconversion and specific IgG concentration against SARS-CoV-2 spike S1 and Receptor Binding Domain (RBD) after the second dose at day 43. We compared results to two historical cohorts of non-hospitalised COVID-19 patients and vaccinated individuals. Findings: Thirty-eight of forty included participants (median age 25 years) completed the study. There were no serious adverse events. Self-reported local adverse reactions after intradermal delivery were mild, both in the 10 µg and the 20 µg group. In the higher dose group, systemic adverse reactions were more common , but still well tolerated. All 38 participants mounted substantially higher IgG-anti-S1 and IgG-anti-RBD concentrations at day 43 than COVID-19 controls. At day 43, anti-S1 (95% CI) was 1,696 (1,309-2,198) BAU/mL for the 10 µg intradermal group, 1,406 (953·5-2,074) BAU/mL for the 20 µg intramuscular group and 2,057 (1,421-2,975) BAU/mL for the 20 µg intradermal group. Anti-S1 was 107·2 (63-182·2) BAU/mL for the convalescent plasma control group and 1,558 (547·8-4,433) BAU/mL for the individuals vaccinated with 100 µg mRNA-1273.Interpretation: Intradermal administration of 10 µg and 20 µg mRNA-1273 vaccine was well tolerated and safe, and resulted in a robust antibody response. Intradermal vaccination has the potential to be deployed for vaccine dose-sparing.Clinical Trial Registration Details: registered in the Netherlands Trial Register (NTR) (https://www.trialregister.nl/trial/9275).Funding Information: The trial was supported by crowdfunding (Wake Up to Corona).Declaration of Interests: All authors declare no competing interests. Ethics Approval Statement: The trial was performed in accordance with the ethical principles of the Declaration of Helsinki and Good Clinical Practice guidelines developed by the International Harmonisation Task Force. The protocol was approved by the Medical Ethical Committee Leiden, Den Haag, Delft (NL 76702.058.21). All participants provided written informed consent. The vaccine manufacturer was not involved in this trial.
Subject(s)
COVID-19ABSTRACT
Background: Faecal microbiota transplantation (FMT) is an efficacious treatment for recurrent Clostridioides difficile infections (rCDI), and seems promising for other microbiota related disorders. Stool banks ensure safe and effective application of FMT by providing screened faecal suspensions from healthy donors. Due to the ongoing coronavirus disease 2019 (COVID-19) pandemic and the potential risk of SARS coronavirus-2 (SARS-CoV-2) transmission via FMT, many stool banks were forced to halt donor activities. Here we describe a strategy to effectively restart stool banking activities during the COVID-19 pandemic.Methods: We implemented periodic SARS-CoV-2 screening in donor faeces and serum, and frequent donor assessment for COVID-19 related symptoms. In this retrospective comparative cohort study, FMT donor and recipient data obtained before (2016-2019) and during the COVID-19 pandemic (March 2020-March 2021) was compared to assess stool banking efficacy.Findings: One active donor developed COVID-19 (10%, 1/10). Of 31 FMT-treated patients, one developed COVID-19 three weeks after FMT. No differences during versus before the COVID-19 pandemic were observed in the number of faecal donations (16 vs 22/month [-13·24-2·26], p=0·1); FMT requests for rCDI (3·8 vs 4·5/month [-2·22-0·83], p=0·3); rCDI patients eligible for FMT (73·8% vs 73·3%, OR=1·03 [0·48-2·21], p=0·9); rCDI cure rate (95·2% vs 89·1%, OR=0·41 [0·05-3·32], p=0·5); CDI free survival (p=0·1); the number of non-rCDI patients treated with FMT (five vs five), and the number of possibly FMT related adverse events (AEs) (12·0% vs 7·8%, OR=1·61 [0·40-6·42], p=0·7). Two FMTs for rCDI were delayed due to COVID-19. Clinical trials were hampered, however two out of three resumed all activities.Interpretation: There is a continued need for FMT treatment of rCDI. By implementing appropriate donor screening and SARS-CoV-2 infection prevention measures, safe, effective and efficient stool banking to facilitate FMT during the COVID-19 pandemic is possible.Funding Information: The Netherlands Donor Feces Bank has received an unrestricted grant of Vedanta Biosciences.Declaration of Interests: We declare no competing interests.Ethics Approval Statement: This study conforms to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in a priori approval by the institution’s Human Research Committee, and was approved on December 16th 2015 by the METC of the LUMC (P15.154). Written informed consent was provided by donors and patients for collection and analysis of clinical data and faeces samples.