Comparison of different methods for viral rna isolation and diagnosis of SARS-CoV-2 (COVID-19)

Medical Review (Med. pregled), 2023, 59(5), 35-42.

N. Kalvatchev, I. Sirakov

Department of Medical Microbiology, Medical Faculty, Medical University ‒ Sofia

Abstract. Since the beginning of the COVID-19 pandemic, diagnostic difficulties began. Our health care system (hospitals, medical centers and private laboratories) were not prepared for mass virological testing for SARS-CoV-2 in suspected patients. Quickly, and step by step, different molecular and rapid immunochromatographic tests have come into widespread use to clarify the diagnosis by specialists and non-specialists personal. On the other hand, accurate analysis of the obtained results determined the course of the therapeutic algorithm in each patient. Here, we share our experience, when working with SARS-CoV-2, from taking the clinical material to the final diagnosis of COVID-19. We compare more than 3,000 samples for advantages and disadvantages of the most commonly used methods for viral RNA purification when operating with SARS-CoV-2, as well as the frequently used direct methods for diagnosis, namely Real time RT-PCR; RT-LAMP, Nested RT-PCR and RAT.

Key words: COVID-19, SARS-CoV-2, diagnosis

Address for correspondence: Assist. Prof. Nikolay Kalvatchev, MD, PhD, Department of Medical Microbiology, Faculty of Medicine, Medical University, 1 Sv. Georgi Sofiyski, Blvd., Bg – 1431 Sofia, Tel: +359 2 917 27 79,
Е-mail: nkalvat@yahoo.com