Journal of clinical microbiology
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J. Clin. Microbiol. · Apr 2021
Performance and Implementation Evaluation of the Abbott BinaxNOW Rapid Antigen Test in a High-Throughput Drive-Through Community Testing Site in Massachusetts.
Rapid diagnostic tests (RDTs) for SARS-CoV-2 antigens (Ag) that can be performed at point of care (POC) can supplement molecular testing and help mitigate the COVID-19 pandemic. Deployment of an Ag RDT requires an understanding of its operational and performance characteristics under real-world conditions and in relevant subpopulations. We evaluated the Abbott BinaxNOW COVID-19 Ag card in a high-throughput, drive-through, free community testing site in Massachusetts using anterior nasal (AN) swab reverse transcriptase PCR (RT-PCR) for clinical testing. ⋯ Excellent interoperator agreement indicates that an individual can perform and read the BinaxNOW test alone. A skilled laboratorian can perform and read 20 tests per hour. Careful attention to temperature is critical.
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J. Clin. Microbiol. · Jan 2021
Comparative StudySaliva Is a Promising Alternative Specimen for the Detection of SARS-CoV-2 in Children and Adults.
Testing efforts for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been burdened by the scarcity of testing materials and personal protective equipment for health care workers. The simple and painless process of saliva collection allows for widespread testing, but enthusiasm is hampered by variable performance compared to that of nasopharyngeal swab (NPS) samples. We prospectively collected paired NPS and saliva samples from a total of 300 unique adult and pediatric patients. ⋯ The overall values for PPA for adults were 83.3% and 90.7% for saliva and NPS, respectively, with saliva yielding detection of 4 fewer cases than NPS. However, saliva performance for symptomatic adults was identical to NPS performance (PPA of 93.8%). With lower cost and self-collection capabilities, saliva can be an appropriate sample choice alternative to NPS for detection of SARS-CoV-2 in children and adults.
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J. Clin. Microbiol. · Jan 2021
Inference of Active Viral Replication in Cases with Sustained Positive Reverse Transcription-PCR Results for SARS-CoV-2.
The purpose of this study was to detect coronavirus disease 2019 (COVID-19) cases with persistent positive reverse transcription-PCR (RT-PCR) results for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), for which viable virus can be inferred due to the presence of subgenomic (SG) viral RNA, which is expressed only in replicating viruses. RNA remnants purified from diagnostic nasopharyngeal specimens were used as the templates for RT-PCR-specific detection of SG E gene RNA. As controls, we also detected viral genomic RNA for the E gene and/or a human housekeeping gene (RNase P). ⋯ According to the severities of the COVID-19 episodes, they were mild (40%), intermediate (20%), and severe (40%). In a percentage of persistent SARS-CoV-2 PCR-positive cases, the presence of actively replicating virus may be inferred, far beyond diagnosis. We should not assume a universal lack of infectiousness for COVID-19 cases with prolonged viral shedding.
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J. Clin. Microbiol. · Jan 2021
Comparative StudyComparison of the Quidel Sofia SARS FIA Test to the Hologic Aptima SARS-CoV-2 TMA Test for Diagnosis of COVID-19 in Symptomatic Outpatients.
The Quidel Sofia severe acute respiratory syndrome (SARS) fluorescent immunoassay (FIA) test (SOFIA) is a rapid antigen immunoassay for the detection of SARS coronavirus 2 (SARS-CoV-2) proteins from nasal or nasopharyngeal swab specimens. The purpose of this study was to compare the results of the SOFIA test to those of the Hologic Aptima SARS-CoV-2 TMA test (APTIMA TMA), a high-throughput molecular diagnostic test that uses transcription-mediated amplification (TMA) for the detection of SARS-CoV-2 nucleic acid from upper respiratory tract specimens. ⋯ The Cepheid Xpert Xpress SARS-CoV-2 reverse transcription-PCR (RT-PCR) test was used to determine the cycle threshold (CT ) value for any specimens that were discrepant between the SOFIA and APTIMA TMA tests. Using a CT value of ≤35 as a surrogate for SARS-CoV-2 culture positivity, we estimate that the SOFIA test detected 87.2% of symptomatic patients tested ≤5 days from symptom onset who were likely to be culture positive.