EVALUATION OF ALTERNATIVE CLINICAL SAMPLES FOR DETECTION OF SARS-COV-2 RNA AND INFLUENZA VIRUS RNA


Parkan Ö. M., Gökahmetoğlu S., Türe Yüce Z., Sağıroğlu P., Soylu M., Durmaz S., ...More

25th ESCV 2023, Milan, Italy, 30 August - 02 September 2023, pp.72

  • Publication Type: Conference Paper / Summary Text
  • City: Milan
  • Country: Italy
  • Page Numbers: pp.72
  • Erciyes University Affiliated: Yes

Abstract

BACKGROUND-AIM The most commonly used and reliable test for diagnosis of SARS-CoV-2 and influenza virus is reverse transcribed polymerase chain reaction (RT-PCR). Quality of the sample, viral load and analytical sensitivity are critical for the test performance. Aim: To compare the efficiencies of self-collected clinical samples of saliva (S) and nasal swab (ScN) with healthcare-worker-collected nasopharyngeal swab (HCW-NP) for SARS-CoV-2 + Influenza A/B RT-PCR test. METHODS Three clinical samples (S, ScN, HCW-NP) were collected from 404 SARS-CoV-2 and influenza virus infection suspected symptomatic cases (214 female, 190 male; median age 37), who attended Ege University and Erciyes University Hospital between November 11th 2021 – March 25 th 2022. Samples were tested with SARS-CoV-2/Influenza A/B RNA test (Cobas® SARS-CoV-2 & Influenza A/B on Cobas 6800 System; Roche Molecular Systems, USA). According to the algorithm based on identified criteria, SARS-CoV-2 or Influenza virus infection status of all patients was determined. The criteria, compatible with the prospectus, were determined by us. Positive and negative predictive values (PPV, NPV), sensitivity, specificity and coefficient of variation values (CV) of S, ScN and HCW-NP samples were analyzed. Interrater reliability of the results obtained from three different specimen types were calculated based on Cohen’s Kappa values. Pearson correlation coefficient values were used to calculate the correlation of cycle threshold (Ct) results for three different positive specimen types. RESULTS SARS-CoV-2 and Influenza-A infection rates were 42% (n=170) and 7,9% (n=32), respectively. Especially S has a good PPV, NPV, sensitivity and specificity values, also S and ScN have almost perfect correlation (all Kappa values ε0.81; p<0.001) with HCW-NP. But Ct value correlations were weak (all values of “r”: <0.55; p<0.001). All CV results showed that precision of the test was appropriate (all CV values δ6%). CONCLUSIONS Saliva and ScN could be alternatives to each other for qualitative results. Weak Ct value correlations didn’t affect this situation. Considering the compatibility of the results, these easily collectable specimen types will provide fast, effective and early diagnosis with the correct protocol.