Diagnostic accuracy of SARS-CoV-2 rapid antigen self-tests in asymptomatic individuals in the omicron period: a cross-sectional study

Clinical Microbiology and Infection, Journal Year: 2022, Volume and Issue: 29(3), P. 391.e1 - 391.e7

Published: Nov. 13, 2022

To assess the performances of three commonly used antigen rapid diagnostic tests as self-tests in asymptomatic individuals Omicron period.We performed a cross-sectional test accuracy study period public health service COVID-19 sites Netherlands, including 3600 aged ≥ 16 years presenting for SARS-CoV-2 testing any reason except confirmatory after positive self-test. Participants were sampled RT-PCR (reference test) and received one self-test (either Acon Flowflex [Flowflex], MP Biomedicals (MPBio), or Siemens-Healthineers CLINITEST [CLINITEST]) to perform unsupervised at home. Diagnostic accuracies each calculated.Overall sensitivities 27.5% (95% CI, 21.3-34.3%) Flowflex, 20.9% (13.9-29.4%) MPBio, 25.6% (19.1-33.1%) CLINITEST. After applying viral load cut-off (≥5.2 log10 E-gene copies/mL), increased 48.3% (37.6-59.2%), 37.8% (22.5-55.2%), 40.0% (29.5-51.2%), respectively. Specificities >99% all most analyses.The when very low. Antigen self-testing may only detect minority infections that point time. Repeated case negative is advocated improve yield, should be advised re-test symptoms develop.

Language: Английский

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COVID-19 study quantifying daily viral loads confirms throat samples are key to early diagnosis

Diagnostic Microbiology and Infectious Disease, Journal Year: 2025, Volume and Issue: 111(4), P. 116742 - 116742

Published: Feb. 13, 2025

Language: Английский

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Longitudinal observation of viral load in patients infected with Omicron variant and its relationship with clinical symptoms

Frontiers in Microbiology, Journal Year: 2023, Volume and Issue: 13

Published: Jan. 13, 2023

In 2022, a new coronavirus variant (Omicron) infection epidemic broke out in Shanghai, China. However, it is unclear whether the duration of this omicron different from that prototype strain.We retrospectively analyzed 157 cases Omicron Taizhou Public Health Center March 29, to April 18, and observed dynamics nucleic acid Ct values during admission discharge patients. Clinical laboratory indicators these patients were also obtained.Compared strain, showed broad population susceptibility infected individuals (regardless age presence underlying disease) had slight damage immune system renal function; viral loads peaked was 2-3 days disease onset; median 15-18 days; value nasopharyngeal swabs lower than throat swabs, oropharyngeal unstable recovery period.Therefore, we found time peak load after onset disease, symptomatic higher longer hospitalization time. This finding will provide basis for understanding variants formulating national prevention control strategy.

Language: Английский

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A Community Study of SARS-CoV-2 Detection by RT-PCR in Saliva: A Reliable and Effective Method

Viruses, Journal Year: 2022, Volume and Issue: 14(2), P. 313 - 313

Published: Feb. 2, 2022

Efficient, wide-scale testing for SARS-CoV-2 is crucial monitoring the incidence of infection in community. The gold standard COVID-19 diagnosis molecular analysis epithelial secretions from upper respiratory system captured by nasopharyngeal (NP) or oropharyngeal swabs. Given ease collection, saliva has been proposed as a possible substitute to support at population level. Here, we used novel collection device designed favour safe and correct acquisition sample, well processivity downstream analysis. We tested 1003 swabs paired samples self-collected individuals recruited public drive-through facility. An overall moderate concordance (68%) between two tests was found, with evidence that neither can diagnose 100% cases. While methods performed equally symptomatic individuals, their discordance mainly restricted convalescent subjects. test least effective NP asymptomatic contact tracing. Our study describes strategy samples, which reliable screening community particularly

Language: Английский

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A mixed methods study evaluating acceptability of a daily COVID-19 testing regimen with a mobile-app connected, at-home, rapid antigen test: Implications for current and future pandemics

PLoS ONE, Journal Year: 2022, Volume and Issue: 17(8), P. e0267766 - e0267766

Published: Aug. 8, 2022

Widespread use of at-home rapid COVID-19 antigen tests has been proposed as an important public health intervention to interrupt chains transmission. Antigen may be preferred over PCR because they provide on-demand results for relatively low cost and can identify people when are most likely infectious, particularly used daily. Yet the extent which a frequent testing will result in positive impact depend on high acceptability adherence such regimens.We conducted mixed-methods study assessing daily mobile-app connected regimen among employees US-based media company. Acceptability was assessed across seven domains Theoretical Framework Acceptability.Among 31 participants, generally high, with participants reporting perceived effectiveness, coherence, self-efficacy; affective attitude; acceptable degree burden opportunity cost; ethical. 71% reported preference test using than weekly employment-based PCR. Mean 21-day 88% 43% achieving 100% adherence, 48% at least every other day, 10% less day.Despite overall we identified three implementation challenges that must addressed serial implemented scale have impact. First, users need guidance how adapt frequencies different epidemiological conditions. Second, institutions guidelines safely store share results. Third, strategies prioritize equity protect those vulnerable COVID-19.

Language: Английский

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Sensitivity of Rapid Antigen Tests Against SARS-CoV-2 Omicron and Delta Variants

medRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Feb. 10, 2023

Rapid Antigen Tests (RAT) have become an invaluable tool for combating the COVID-19 pandemic. However, concerns been raised regarding ability of existing RATs to effectively detect emerging SARS-CoV-2 variants. We compared performance eight commercially available, emergency use authorized against Delta and Omicron variants using individual patient serially diluted pooled clinical samples. The exhibited lower sensitivity samples when PCR Cycle threshold (C

Language: Английский

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Comparative Diagnostic Utility of SARS-CoV-2 Rapid Antigen and Molecular Testing in a Community Setting

The Journal of Infectious Diseases, Journal Year: 2024, Volume and Issue: 230(2), P. 363 - 373

Published: March 26, 2024

SARS-CoV-2 antigen-detection rapid diagnostic tests (Ag-RDTs) have become widely utilized but longitudinal characterization of their community-based performance remains incompletely understood.

Language: Английский

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Ct values of different SARS CoV2 variants: a single center observational study from Innsbruck, Austria

Clinical Chemistry and Laboratory Medicine (CCLM), Journal Year: 2022, Volume and Issue: 60(10), P. e225 - e227

Published: Aug. 8, 2022

Article Ct values of different SARS CoV2 variants: a single center observational study from Innsbruck, Austria was published on September 1, 2022 in the journal Clinical Chemistry and Laboratory Medicine (CCLM) (volume 60, issue 10).

Language: Английский

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Performance of High Throughput SARS-CoV-2 Antigen Testing Compared to Nucleic Acid Testing

Laboratory Medicine, Journal Year: 2022, Volume and Issue: 54(2), P. e54 - e57

Published: Sept. 6, 2022

Independent assessment of SARS-CoV-2 antigen (COV2Ag) tests remains important as varying performance between assays is common. We assessed the a new high-throughput COV2Ag test compared to nucleic acid amplification (NAAT).A total 347 nasopharyngeal samples collected from January October 2021 were by NAAT part standard-of-care testing (CDC LDT or GeneXpert System, Cepheid) and using ADVIA Centaur CoV2Ag assay (Siemens Healthineers).Among positive specimens we found 82.4% agreement in negative 97.3% (overall 85.6%). In symptomatic persons, agreed with 90.0% (n = 291), asymptomatic 62.5% 56). Agreement increased at lower cycle threshold (Ct) values.The exceeded World Health Organization minimum requirements ≥ 80% sensitivity 97% specificity. The helpful for large scale screening efforts due reduced wait times.

Language: Английский

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Prevalence of Positive Rapid Antigen Tests After 7-Day Isolation Following SARS-CoV-2 Infection in College Athletes During Omicron Variant Predominance

JAMA Network Open, Journal Year: 2022, Volume and Issue: 5(10), P. e2237149 - e2237149

Published: Oct. 18, 2022

Importance The US Centers for Disease Control and Prevention shortened the recommended isolation period SARS-CoV-2 infection from 10 days to 5 in December 2021. It is unknown whether an individual with may still have a positive result rapid antigen test potentially be contagious at end of this period. Objective To estimate proportion individuals whose starting 7 postdiagnosis. Design, Setting, Participants This case series analyzed student athletes National Collegiate Athletic Association Division I university campus who tested between January 3 May 6, 2022. Individuals underwent testing postdiagnosis determine they could their Exposures Rapid after SARS-CoV-2. Main Outcomes Measures results, symptom status, variant identification via wastewater analysis. Results A total 264 (140 [53%] female; mean [SD] age, 20.1 [1.2] years; range, 18-25 years) representing 268 infections (177 [66%] symptomatic, 91 [34%] asymptomatic) were included study. Of 248 did day test, 67 (27%; 95% CI, 21%-33%) tests positive. Patients symptomatic significantly more likely on vs those asymptomatic (35%; 28%-43% 11%; 5%-18%; P < .001). BA.2 also compared BA.1 (40%; 29%-51% 21%; 15%-27%; = .007). Conclusions Relevance In series, remained 27% isolation, suggesting that Prevention–recommended 5-day insufficient preventing ongoing spread disease. Further studies are needed these findings present heterogeneous population subsequent variants.

Language: Английский

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