SARS-CoV-2 detection by direct rRT-PCR without RNA extraction.

Area of Science:

• Molecular Biology
• Virology
• Diagnostic Assays

Background:

• Rapid and reliable SARS-CoV-2 screening is crucial for pandemic control.
• Real-time reverse transcription PCR (rRT-PCR) is a key diagnostic tool for detecting SARS-CoV-2.
• Optimizing rRT-PCR workflows, including RNA extraction, can improve efficiency.

Purpose of the Study:

• To compare the efficiency of direct rRT-PCR (without RNA extraction) using SeeGene AllplexTM 2019-nCoV and RealStar® SARS-CoV-2 kits.
• To evaluate the impact of different swab storage media on rRT-PCR efficiency for SARS-CoV-2 detection.

Main Methods:

• Direct rRT-PCR assays were performed without prior RNA extraction.
• Two commercial kits, SeeGene AllplexTM 2019-nCoV and RealStar® SARS-CoV-2, were compared.
• The effect of storage media (UTM, molecular water, saline, Hanks medium) on PCR efficiency was assessed.

Main Results:

• Both SeeGene and Altona diagnostic assays demonstrated similar efficiency for SARS-CoV-2 detection.
• Direct rRT-PCR without RNA extraction was feasible when samples were stored in UTM medium or molecular water.
• RNA extraction was necessary when samples were stored in saline solution or Hanks medium.

Conclusions:

• Direct rRT-PCR without RNA extraction is a viable and efficient method for SARS-CoV-2 detection under specific storage conditions.
• The choice of swab storage medium significantly impacts the success of bypassing RNA extraction in rRT-PCR assays.
• These findings can inform optimized SARS-CoV-2 testing strategies, potentially reducing turnaround times and costs.