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VOLUME 6 , ISSUE 2 ( April-June, 2023 ) > List of Articles

Original Article

Comparison of Extraction Free Dry Swab with Standard Extraction-based RT-PCR Method for Diagnosis of SARS-CoV-2

Chaitali Nikam, Smita Santosh Chavhan, Caesar Sengupta, Praveenkumar Ganesan, Balkrishna Adsul, Chandrakant Narkhede, Prasad Tukaram Dhikale

Keywords : COVID-19, Dry swab, Extraction free, Pandemic, Reverse-transcription polymerase chain reaction, Severe acute respiratory syndrome coronavirus 2

Citation Information : Nikam C, Chavhan SS, Sengupta C, Ganesan P, Adsul B, Narkhede C, Dhikale PT. Comparison of Extraction Free Dry Swab with Standard Extraction-based RT-PCR Method for Diagnosis of SARS-CoV-2. 2023; 6 (2):29-32.

DOI: 10.5005/jp-journals-10082-03191

License: CC BY-NC 4.0

Published Online: 13-04-2023

Copyright Statement:  Copyright © 2023; The Author(s).


Background: Coronavirus disease-19 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) which had become a global pandemic leading to a great loss of lives and severe social and economic disruption. Accurate identification of the infected individuals is needed to control and reduce the spread of infection. Recently, an advisory has been issued by the Indian Council of Medical Research (ICMR) for using extraction free dry swab (EFDS) protocol to detect SARS-CoV-2 (COVID-19) with the aid of real-time reverse-transcription polymerase chain reaction (PCR). Materials and methods: During the study, we have done a comparison of two methods on 500 clinical samples. Results obtained with EFDS were compared using the extraction-dependent viral transport medium (VTM) as a comparative method for the diagnosis of SARS-CoV-2. Results: The overall performance of the EFDS method while compared with the comparative method showed 59 discordant results with a sensitivity of 85.65% and specificity of 98.47% with an accuracy of 92.48%. Conclusion: This study shows that the EFDS shows comparable results with extraction-dependent VTM as a comparative method for the detection of SARS-CoV-2, dry swab method reduces and simplifies the workflow, reduces turnaround time, and is cost-effective.

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