Patient-collected tongue, nasal, and mid-turbinate swabs for SARS-CoV-2 yield equivalent sensitivity to health care worker collected nasopharyngeal swabs

BackgroundCurrent testing for SARS-CoV-2 requires health care workers to collect a nasopharyngeal (NP) sample from a patient. NP sampling requires the use of personal protective equipment that are in limited supply, is uncomfortable for the patient, and reduces clinical efficiency. This study explored the equivalency of patient-collected tongue, anterior nares (nasal), and mid-turbinate (MT) samples to health care worker-collected NP samples for detecting SARS-CoV-2. MethodsPatients presenting to five urgent care facilities with symptoms indicative of an upper respiratory infection provided self-collected samples from three anatomic sites along with a health care worker-collected NP sample. Using NP as the comparator, sensitivities and one-sided 95% confidence intervals for the tongue, nasal, and MT samples for detection of SARS-CoV-2 were calculated. ResultsThe sensitivity for detecting SARS-CoV-2 in patient-collected tongue, nasal, and mid-turbinate samples was 89.8% (95% CI: 80.2 -100.0), 94.0 (95% CI: 84.6-100.0) and 96.2 (95% CI: 87.7-100.0), respectively. Among samples yielding positive results, cycle threshold (Ct) values (a measure of viral load) had correlation coefficients of 0.48, 0.78, and 0.86 between the NP samples and the tongue, nasal, and MT samples, respectively. ConclusionsPatient-collected nasal and MT samples demonstrated high sensitivity for SARS-CoV-2 detection using health care worker-collected NP samples as the comparator. Among patients testing positive with NP samples, nasal and MT Ct values demonstrated high correlations with those Ct values of the NP samples. Patient-collected nasal or MT sampling may improve efficiency for COVID-19 testing while reducing the risk of exposure of the health workforce.