Rapid Detection of COVID-19 by RT-LAMP PCR Technique and its Comparison with Real-Time RT-PCR Method

 Rapid antigen and antibody, serological tests, and RT ‑ PCR-based molecular methods are widely used to detect microorganisms worldwide. This study aimed to detect the covid-19 using Isothermal nucleic acid amplification techniques.

 In this study, we collected 200 samples of nasopharynx and oropharynx from Jamaran Heart Hospital in Tehran. Covid -19 was examined by LAMP-RT PCR and Real-Time RT- PCR techniques. The nasopharynx and oropharynx nucleic acids were extracted both by pishtaz RNA extraction kit. LAMP-RT-PCR was performed on direct samples, while Real-Time RT-PCR samples were tested only using RNA extraction samples. The probe-primer mixture of this kit was designed using a dual-target gene method that simultaneously targets the genomic sequences of the spike region and N nucleocapsid. Fluorescence was measured using Real-Time RT-PCR and LAMP-RT PCR.

Clinical specimens (56%) were positive using Real-Time RT-PCR technique, with mean Ct values less than 30. Clinical samples (52%) were positive for Covid-19 in the RT-LAMP technique of RNA extraction samples. RT-LAMP technique indicated a sensitivity of 92.8%. Also in the RT-LAMP method without RNA extraction, the sensitivity of the technique was 85.7%.

 The LAMP-RT PCR technique is emerging as an appropriate alternative to the Real-Time RT-PCR method. This technique has basic advantages, such as constant temperature amplification, thermal cycle elimination, faster results, and potentially greater detection capacity. Therefore, the RT-LAMP-PCR can be used as a quick and cost-effective technique that can be employed in all areas.