DRUL for school: Opening Pre-K with safe, simple, sensitive saliva testing for SARS-CoV-2.

Area of Science:

• Molecular Biology
• Virology
• Public Health

Background:

• The COVID-19 pandemic necessitates accessible and reliable diagnostic tools.
• Existing SARS-CoV-2 tests often require trained personnel and invasive sample collection.
• There is a need for scalable, user-friendly testing solutions for community surveillance.

Purpose of the Study:

• To validate and implement a novel, at-home saliva-based PCR test for SARS-CoV-2 detection.
• To assess the sensitivity, stability, and safety of the saliva assay.
• To evaluate the utility of the saliva test for large-scale screening in diverse populations.

Main Methods:

• Validation of a reverse transcription PCR (RT-PCR) assay using self-collected saliva preserved in Darnell Rockefeller University Laboratory (DRUL) buffer.
• Determination of the limit of detection (LOD) and RNA stability at room temperature.
• Safety assessment of DRUL buffer for viral inactivation.
• Comparative analysis with FDA Emergency Use Authorization (EUA) nasopharyngeal (NP) and oropharyngeal (OP) swab tests.

Main Results:

• The DRUL saliva assay demonstrated a limit of detection of 1 viral copy/μl.
• Viral RNA remained stable in DRUL buffer for up to seven days at room temperature.
• DRUL buffer effectively inactivated SARS-CoV-2 at high concentrations.
• High correlation was observed between saliva and NP swab results, with saliva assay identifying four additional positive cases.

Conclusions:

• The validated DRUL saliva assay is a simple, sensitive, stable, and safe method for SARS-CoV-2 detection.
• Self-collected saliva PCR testing is a valuable tool for clinical diagnosis and screening in schools and workplaces.
• The assay facilitates safe reopening of educational settings through effective monitoring and quarantine of at-risk individuals.