SARS-COV-2 DETECTION IN SALIVA SAMPLES FROM SYMPTOMATIC AND ASYMPTOMATIC HEALTH CARE WORKERS USING A HOMEBREW MULTIPLEX RT-PCR AND A COMMERCIAL KIT (REAL STAR KIT, ALTONA).

RODRIGUEZ PAMELA ELIZABETH; SCHWALD ISABEL; ECHAVARRIA, MARCELA; REYES, NOELIA SOLEDAD; HERMIDA ELIANA; CARBALLAL, GUADALUPE; JARA RAQUEL; RICARTE CARMEN

Conferencia; 24th Annual Conference of the European Society for Clinical Virology; 2022

BackgroundCurrent diagnostic standards of SARS‐CoV‐2 detection involve nasopharyngeal swabs (NPS), but saliva isan attractive and noninvasive option for diagnosis.The aim of this study was to compare a homebrew multiplex RT-PCR with a commercial kit (Real Star Kit,altona) in saliva samples from asymptomatic and symptomatic Health Care Workers (HCWs).MethodsA total of 274 saliva samples were collected (174 from symptomatic and 100 from asymptomatic HCWs)and tested with a homebrew RT-PCR multiplex assay (targeting gen E of SARS-CoV-2 and the humanRNAsa P gene) and the Real Star Kit (altona).The limit of detection was determined by testing serial dilutions of a quantified transcript of E gene.Sequencing of the segment between nucleotides 22874-23812 (aa 428-750) in 2 saliva samples wasperformed. New samples are being tested for phylogenetic analysis.ResultsThe prevalence of SARS-CoV-2 in saliva from HCW was 24.8%. 68/274 samples were positive with thehomebrew assay and 60/274 with Real Start (sensibility: 88.2%). Samples that were positive only withthe homebrew assay had Ct values higher than 28 (mean Ct value 31.82; range, 28.93–39.22).Limit of detection for the homebrew assay and the commercial assay for SARS‐CoV‐2 was 1 copy/µl and10 copies/µl, respectively.ConclusionsThe correlation between both assays was high, the sensibility was 88.2%.Saliva samples are easier to collect, and allow a better surveillance of HCW´s health status.