1. Effect of RNA quality to SARS-CoV-2 RT-qPCR detection from saliva
- Author
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Susanna Paju, Marika Tallgren, Anne Kivimäki, Laura Lahdentausta, Aino Salminen, Lotta Oksanen, Enni Sanmark, Ahmed Geneid, Pirkko Pussinen, Milla Pietiäinen, HUS Head and Neck Center, Department of Oral and Maxillofacial Diseases, Clinicum, Department of Pharmacology, Medicum, Korva-, nenä- ja kurkkutautien klinikka, and Faculty Common Matters (Faculty of Medicine)
- Subjects
11832 Microbiology and virology ,susanna ,Microbiology (medical) ,paju@helsinki ,SARS-CoV-2 ,RT-qPCR ,COVID-19 ,Reproducibility of Results ,General Medicine ,fi SARS-CoV-2 ,Microbiology ,Specimen Handling ,Nasopharynx ,Humans ,RNA, Viral ,Saliva - Abstract
Saliva is an alternative sample material to nasopharyngeal swab in SARS-CoV-2 diagnostics. We investigated possible aspects to improve the reliability of SARS-CoV-2 detection from saliva. Saliva was collected from asymptomatic healthy subjects (n=133) and COVID-19 patients (n=9). SARS-CoV-2 detection was performed with quantitative reverse-transcriptase PCR (RT-qPCR) with two viral and one host target serving as an internal control. The use of internal control revealed that in the first RT-qPCR run 25–30 % of assays failed. The failure is associated with poor RNA quality. When the amount of RNA was cut down to half from the original amount, the performance of RT-qPCR was greatly enhanced (95 % of the assays succeeded). The quality of RNA was not affected by the use of different nucleic acid stabilizing buffers. Our study showed that saliva is suitable material for RT-qPCR based SARS-CoV-2 diagnostics, but the use of internal control is essential to distinguish the true negative samples from failed assays.
- Published
- 2022