Related Experiment Video
Updated: Jan 7, 2026
Author Spotlight: Advancing Pathogen Diagnostics with Standardized LAMP
Published on: September 8, 2023
Diagnostic accuracy of point-of-care testing methods for SARS-CoV-2 detection in community quarantine and isolation
Simon Ching Lam1,2, Jing Jing Su2, Shun Wa Tsang3
1Integrative Health Centre, Tung Wah College, Hong Kong Special Administrative Region of China.
Insights
Fluorescence-based rapid antigen tests (RAT) and point-of-care quantitative PCR offer reliable COVID-19 diagnosis. These methods show higher sensitivity than conventional RAT, making them effective alternatives to RT-PCR.
Area of Science:
- Medical Diagnostics
- Infectious Disease Testing
- Public Health
Background:
- Reverse transcriptase polymerase chain reaction (RT-PCR) is the gold standard for COVID-19 diagnosis.
- Rapid antigen tests (RAT) and point-of-care testing (POCT) methods were developed for rapid COVID-19 screening during surges.
- The diagnostic accuracy of these rapid methods needed further evaluation.
Purpose of the Study:
- To evaluate the diagnostic accuracy of conventional RAT, fluorescence-based RAT (Fluorescent-RAT), and POCT quantitative PCR (qPCR) for COVID-19.
- To compare the performance of these rapid tests against the reference standard RT-PCR.
- To determine if rapid POCT methods can serve as reliable alternatives for COVID-19 diagnosis.
Main Methods:
- 186 participants (86 positive, 100 negative) were recruited.
- Four nasal swabs were collected per participant.
- Three swabs were tested with conventional RAT, Fluorescent-RAT, and POCT qPCR; the fourth was used for laboratory RT-PCR.
Main Results:
- Fluorescent-RAT sensitivity: 87.21% (95% CI: 80.15%-94.27%).
- POCT qPCR sensitivity: 84.27% (95% CI: 76.71%-91.83%).
- Conventional RAT sensitivity: 51.69% (95% CI: 41.30%-62.07%).
- All methods showed high specificity: RAT and POCT qPCR (100%), Fluorescent-RAT (97.06%).
Conclusions:
- Fluorescent-RAT and POCT qPCR demonstrated significantly higher sensitivity than conventional RAT.
- These rapid POCT methods are reliable alternatives to RT-PCR for COVID-19 diagnosis.
- The findings support the use of Fluorescent-RAT and POCT qPCR for efficient COVID-19 screening.
Abstract:
Reverse transcriptase polymerase chain reaction (RT-PCR) testing has been regarded as the gold standard for the diagnosis of coronavirus disease 2019 (COVID-19). In response to the sudden surge in cases that overwhelmed the healthcare system in Hong Kong, several point-of-care testing (POCT) methods have been developed for rapid COVID-19 screening. However, the diagnostic accuracy of these methods remains inadequately established. COVID-19-positive patients and negative control subjects were recruited from a community isolation centre and individuals under home quarantine. Four nasal swab samples were collected by trained operators from each subject. Three swab samples were immediately tested using conventional COVID-19 rapid antigen test (RAT), fluorescence-based RAT (Fluorescent-RAT) and POCT quantitative polymerase chain reaction (qPCR). The fourth swab sample was submitted to a certified laboratory for standard RT-PCR analysis. The sensitivity and specificity of the three rapid testing methods were evaluated against the results obtained from the certified laboratory-based RT-PCR, which served as the reference standard. The performance of the three diagnostic methods was assessed in 186 valid cases, which comprised 86 RT-PCR-confirmed positive cases and 100 negative cases. The participants' age ranged from 3 years to 94 years. The sensitivity of the Fluorescent-RAT (87.21%, 95% confidence interval [CI]:80.15%-94.27%) and the POCT qPCR (84.27%, 95% CI:76.71%-91.83%) was comparable and significantly higher than that of the conventional RAT (51.69%, 95% CI:41.30%-62.07%). All three methods demonstrated high specificity. The RAT and POCT qPCR exhibited 100% specificity (95% CI:100%), and the Fluorescent-RAT showed a specificity of 97.06% (95% CI:93.78%-100%). This study demonstrated that the Fluorescent-RAT and POCT qPCR can serve as reliable alternatives to RT-PCR for COVID-19 diagnosis, offering improved performance compared with the conventional RAT.
