Pengaruh Kualitas Penyimpanan Spesimen Tes Diagnositik Sars-Cov-2 Terhadap Cycle Threshold (Ct) Range di Medan, Sumatera Utara

Abstract

Coronavirus (COVID-19) pandemic is an infectious disease which has resulted in 643,176,637 confirmed cases and 6,634,815 deaths worldwide. RT-PCR examination of naso/oropharyngeal swab specimens is the Gold Standard in diagnosing Covid-19. This study aimed to determine the effect of nasopharyngeal swab specimen storage on CT values. The swab samples were taken randomly from 30 patients at Martha Friska Multatuli Hospital, Medan. The swab samples were obtained from the suspected patients or the person who had close contacts with them. The confirmed RT-PCR results had been confirmed by RNA extraction, and cDNA synthesized using an RT-PCR machine. From the 30 samples, there were 18 samples positive 12 samples were negative. Among 6 positive samples, there were samples had 2 low CT value, 2 with medium CT, and the others 2 had high CT values. Those samples were stored at temperature storage of -20°C and temperature storage of 4°C. The positive samples from each group were grouped again according to the CT ORF1ab value. The result shows the viral load value obtained in each treatment gave an different CT values in storage temperature. The positive samples could be stored at -20°C for 5 days without losing positivity, the samples with low CT and medium CT viral loads could be stored at -20°C for 12 days without losing positivity. However, the samples with high CT values could not be stored for 12 days at -20°C