High performance of a novel antigen detection test on nasopharyngeal specimens for diagnosing SARS‐CoV‐2 infection

Abstract

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has become a major public health issue worldwide. Developing and evaluating rapid and easy-to-perform diagnostic tests is a high priority. The current study was designed to assess the diagnostic performance of an antigen-based rapid detection test (COVID-VIRO ® ) in a real-life setting. Two nasopharyngeal specimens of symptomatic or asymptomatic adult patients hospitalized in the Infectious Diseases Department or voluntarily accessing the COVID-19 Screening Department of the Regional Hospital of Orléans, France, were concurrently collected. The diagnostic specificity and sensitivity of COVID VIRO® results were compared to those of real-time reversetranscriptase quantitative polymerase chain reaction (RT-qPCR) results. A subset of patients underwent an additional oropharyngeal and/or saliva swab for rapid testing. A total of 121 patients confirmed to be infected and 127 patients having no evidence of recent or ongoing infection were enrolled for a total of 248 nasopharyngeal swab specimens. Overall, the COVID-VIRO® sensitivity was 96.7% (CI, 93.5%-99.9%). In asymptomatic patients, symptomatic patients having symptoms for more than 4 days and those with an RT-qPCR cycle threshold value ≥ 32, the sensitivities were 100%, 95.8%, and 91.9%, respectively. The concordance between RT-qPCR and COVID VIRO® rapid test results was 100% for the 127 patients with no SARS-CoV-2 infection. The COVID-VIRO® test had 100% specificity and sensitivity greater than 95%, which are better than the recommendations set forth by the WHO (specificity ≥ 97%-100%, sensitivity ≥ 80%). These rapid tests may be particularly useful for large-scale screening in emergency departments, low-resource settings, and airports.

Diagnostic Utility of Antigen Detection Rapid Diagnostic Tests for Covid- 19: a Systematic Review and Meta-analysis

“…Studies that evaluated different types of samples revealed that nasal examination swabs and saliva specimens for RDTs are associated with lower sensitivity (30). Our results showed the most collected samples were nasopharyngeal swabs; in this line, it was shown examine nasopharyngeal swab, the sensitivity of RDTs results increases (10,41). After evaluating various specimens, Yamayoshi et al found that soaking specimen directly to the lysing buffer can improve RDTs sensitivity (41).…”

“…The possible interference of time of testing cannot be ruled out. Some researchers revealed that testing less than 5 days from the onset of symptoms increases sensitivity (9,10,23,31). It is inconsistent with previous reports that a load of infectious virus decreases after 7-10 days (10,45).…”

“…Some researchers revealed that testing less than 5 days from the onset of symptoms increases sensitivity (9,10,23,31). It is inconsistent with previous reports that a load of infectious virus decreases after 7-10 days (10,45). In one recent wellknown recent experiment, Albert et al with considering the age of participants found the sensitivity of RDTs is lower in pediatrics than adults (9).…”

“…Summary ROC curves constructed for all assays based on Monte Carlo simulations are shown in Fig.2. It did not apply to assessing the false results, because 7 studies (35%) did not focus on false results (8,10,23, 28,31,33, 38,39). Some of the current kinds of literature which focused on Ab rapid tests were excluded due to reporting the results as the separate sensitivity for IgG and IgM or analyzed data based on onset of symptoms(4,40).…”

Greater public health impact of COVID-19 antigen detection tests

“…The sensitivity of antigen detection tests are generally lower than that of nucleic acid tests, even though their specificity are comparable. Currently, a new COVID-19 antigen detection test with higher sensitivity (greater than 95%) and 100% specificity is available [3]. Antigen detection tests with high sensitivity and specificity are expected to play an increasingly important role in the early diagnosis of SARS-CoV-2 infection and will be more useful in hospitals, communities, and airports around the world.…”