SARS-COV-2 DETECTION IN SALIVA FROM SYMPTOMATIC VOLUNTEERS AND ASYMPTOMATIC HEALTH CARE WORKERS USING A HOME BREW MULTIPLEX RT-PCR AND A COMMERCIAL KIT (REAL STAR® KIT, ALTONA)

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

Congreso; 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 is an 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 human RNAsa 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 was performed. 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 the homebrew assay and 60/274 with Real Start (sensibility: 88.2%). Samples that were positive only with the 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 and 10 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.