Testing individual and pooled saliva samples for sars-cov-2 nucleic acid: a prospective study

Area of Science:

• Virology
• Infectious Diseases
• Diagnostic Testing

Background:

• The rapid spread of SARS-CoV-2 necessitates efficient and accessible diagnostic methods.
• Nasopharyngeal swabs are common but invasive for detecting SARS-CoV-2 RNA.
• Exploring non-invasive sample types like saliva is crucial for large-scale testing efforts.

Purpose of the Study:

• To evaluate the sensitivity of saliva samples for SARS-CoV-2 detection compared to nasopharyngeal swabs.
• To assess the performance of pooled saliva samples for SARS-CoV-2 RNA testing.
• To determine the suitability of saliva as a non-invasive specimen for COVID-19 diagnostics.

Main Methods:

• Collected paired nasopharyngeal swabs and saliva samples from 303 subjects.
• Tested individual and pooled saliva samples, alongside nasopharyngeal swabs, for SARS-CoV-2 RNA using Aptima™ assay and a laboratory-developed test (LDT) on the Panther-Fusion™ Hologic® platform.
• Analyzed sensitivity and specificity of saliva versus nasopharyngeal swabs for SARS-CoV-2 detection.

Main Results:

• Saliva testing demonstrated high sensitivity (80-87.5%) compared to nasopharyngeal swabs (96.4%).
• Pooled saliva samples showed comparable sensitivity (72.7-75%) to individual saliva samples.
• No significant difference in sensitivity was observed between pooled and individual saliva testing.

Conclusions:

• Saliva specimens are suitable for sensitive, non-invasive detection of SARS-CoV-2 nucleic acid.
• Pooling saliva samples can enhance laboratory throughput for SARS-CoV-2 testing.
• Saliva-based testing offers a viable alternative for efficient COVID-19 surveillance and diagnosis.