DRY SWAB TEST

Subject: Science & tech

Context : The CSIR (Council of Scientific and Industrial Research)-Centre for Cellular and Molecular Biology (CCMB) got permission from the Indian Council of Medical Research (ICMR) to commercially use the “game-changing technology” of dry swab RNA-extraction-free testing method for COVID-19.

Concept:

• Currently, the preferred protocol for testing uses the RT-PCR (Reverse Transcription-Polymerase Chain Reaction) test which is times consuming and expensive.
• In the usual method of testing, nasal swabs collected from a person are placed in a viral transport medium (VTM).
• From this, a part of the liquid is taken, the viral RNA is extracted and RT-PCR test is carried out.
• The remainder is stored. It is the step of isolating the RNA that takes time and is expensive.
• The standard method is also known to have a problem of false negatives.
• The dry swab technique also does not require the RNA-extraction process, and can be directly used for RT-PCR testing with sensitivity and specificity similar to the current gold standard.