英文摘要 |
Purposes: The real-time reverse transcription-polymerase chain reaction (RT-PCR) of viral RNA is the gold standard for the diagnosis of SARS-CoV-2 infection. However, the operations are time-consuming and is, therefore, not suitable for every patient. In contrast, the rapid antigen test (RAT) for SARS-CoV-2 provides rapid and simple COVID-19 diagnosis at low costs. However, it is pivotal to determine the sensitivity and usage strategies of RAT. This study attempts to retrospectively explore the impact of prevalence rate of COVID-19 on RAT results. Methods: Data from May 1 to August 31, 2021 were retrospectively collected and analyzed. These patients required surgical operations for symptomatic or non-symptomatic diseases, and had been admitted to the emergency departments where they received RAT for COVID-19. Subjects with positive results were quarantined immediately and RT-PCR tests were performed. Results: A total of 1,795 participants had both RAT and RT-PCR results. The assessment of the effect of the prevalence rate on RAT showed that the positive predictive value (PPV) was 60% in May (sensitivity: 48.0%, specificity: 96.2%), 81% in June (sensitivity: 100%, specificity: 99.2%), 12% in July (sensitivity: 100%, specificity: 96.2%), and 0% in August (sensitivity: 0%, specificity: 97.2%). The false positive rates were 40%, 19%, 88%, and 100%, respectively. Conclusions: RAT could be used to screen the patients for triage and identify COVID-19 infection given the high prevalence rate among the high-risk population. However, RAT is less sensitive than RT-PCR. Due to the limitation of sensitivity, the majority of the results obtained from symptomatic cases were positive. Therefore, it is still possible that some of these results were false-negatives. The clinical decision-making should still be made based on confirmatory testing with RT-PCR given a negative RAT result. Currently, there are some novel mutations and variant strains of SARS-CoV-2. The impact of mutations and variant strains on the sensitivity of RAT may be explored in the future. |