ABSTRACT
Introduction Accurate point-of-care testing for SARS-CoV-2 could quickly identify which patients need to be isolated and improve flow for patients being admitted as an emergency to the hospital. We evaluated two diagnostic tests with shorter turnaround times, the Siemens Clinitest Lateral Flow (Siemens Healthineers AG, Erlangen, Germany) and the Simple AMplification-Based Assay (SAMBA)-2 PCR test against a standard laboratory PCR test. Methods We conducted a prospective diagnostic cohort study in a single English emergency department. Adult participants underwent three swabs: the Siemens Clinitest Lateral Flow Test, the SAMBA-2 and a standard laboratory PCR test. Results A total of 212 participants were recruited. The sensitivity and specificity of the Siemens Clinitest Lateral Flow Test against the laboratory PCR test was 55.6% (95% CI 30.8-78.5) and 100% (95% CI 98.1-100) respectively. The sensitivity and specificity of the SAMBA-2 PCR test against the laboratory PCR test was 60.0% (95% CI 32.3-83.7) and 100% (95% CI 97.9-100) respectively. Conclusion Neither the Siemens Clinitest Lateral Flow Test nor the SAMBA-2 PCR test demonstrated sufficient sensitivity to rule out active SARS-CoV-2 infection. Both tests demonstrated high specificity.
ABSTRACT
Rapid COVID-19 diagnosis in the hospital is essential, although this is complicated by 30%-50% of nose/throat swabs being negative by SARS-CoV-2 nucleic acid amplification testing (NAAT). Furthermore, the D614G spike mutant dominates the pandemic and it is unclear how serological tests designed to detect anti-spike antibodies perform against this variant. We assess the diagnostic accuracy of combined rapid antibody point of care (POC) and nucleic acid assays for suspected COVID-19 disease due to either wild-type or the D614G spike mutant SARS-CoV-2. The overall detection rate for COVID-19 is 79.2% (95% CI 57.8-92.9) by rapid NAAT alone. The combined point of care antibody test and rapid NAAT is not affected by D614G and results in very high sensitivity for COVID-19 diagnosis with very high specificity.