RT Journal Article
T1 Point-of-care detection of SARS-CoV-2 antigen among symptomatic vs. asymptomatic persons: Testing for COVID-19 vs. infectivity.
A1 Neukam, Karin
A1 Lucero, Alicia
A1 Gutierrez-Valencia, Alicia
A1 Amaya, Lucas
A1 Echegoyen, Natalia
A1 Martelli, Antonella
A1 Videla, Cristina
A1 Di-Lello, Federico A
A1 Martinez, Alfredo P
K1 COVID-19
K1 PCR
K1 SARS-CoV-2
K1 point-of-care
K1 public health
K1 rapid antigen testing
K1 surveillance
K1 viral kinetics
AB  Management of the coronavirus disease 2019 (COVID-19) pandemic caused by a novel severe acute respiratory syndrome coronavirus-2 ( SARS-CoV-2 ) requires rapid and simple methods to detect COVID-19 patients and identify potential infectors. This study aimed to evaluate the utility of a point-of-care (PoC) rapid antigen diagnostic test (Ag-RDT) in these settings. Patients and methods : Individuals who consecutively presented for SARS-CoV-2 testing at a tertiary care center in Buenos Aires, Argentina , underwent PoC Ag-RDT testing and real- time RT-PCR (qRT- PCR ) on the same day during June 2021.Results: Of 584 included subjects, 108 (18.5%) were symptomatic for COVID-19 while the remaining presented for miscellaneous reasons unrelated to possible or confirmed contact with a SARS-CoV-2 -infected individual. A positive Ag-RDT result was obtained in 26 (24.1%) symptomatic and 7 (1.5%) asymptomatic persons (p < 0.001), which was concordant with qRT- PCR in 105/108 [97.2%, Cohen's kappa coefficient (κ) = 0.927] symptomatic and 467/476 (98.1% κ = 0.563) asymptomatic participants, with a positive percentage agreement (PPA; 95% confidence interval ) of 89.7% (71.5-97.3%) and 42.9% (18.8-70.4%), respectively. None of the 11 false-negative diagnoses showed a Ct-value ≤20. Considering only failures with a Ct-value below 31 as hypothetical infectivity threshold of 105  SARS-CoV-2 RNA copies/mL, concordance was observed in 98.1% (κ = 0.746) in the asymptomatic population , accounting for a PPA of 66.7% (30.9-91%).Conclusions: PoC Ag-RDT accurately detected active SARS-CoV-2 infection and showed acceptable diagnostic performance in asymptomatic persons potentially spreading infectious virus . Ag-RDT may therefore be useful to slow down or stop transmission by enabling adequate decisions on isolation at a public health level.
PB Frontiers Research Foundation
YR 2022
FD 2022-10-17
LK http://hdl.handle.net/10668/20741
UL http://hdl.handle.net/10668/20741
LA en
NO Neukam K, Lucero A, Gutiérrez-Valencia A, Amaya L, Echegoyen N, Martelli A, et al. Point-of-care detection of SARS-CoV-2 antigen among symptomatic vs. asymptomatic persons: Testing for COVID-19 vs. infectivity. Front Public Health. 2022 Oct 17;10:995249.
DS RISalud
RD Jul 7, 2025