Pre-enriched saline gargle samples for detection of SARS-CoV-2

Abstract

A self-collected gargle sample, which avoids discomfort and largely reduces the dependency on medical resources, is emerging for detection of SARS-CoV-2. However, the incomplete usage of starting materials for both routine oropharyngeal swabs (OPS)/nasopharyngeal swabs (NPS) and saline gargle (SG) samples implies sensitivity can be further improved. Presented here is a beadbased strategy for pre-enrichment of SG samples, and results revealed that it acquired about 20 times the starting materials obtained from OPS samples for downstream detection of SARS-CoV-2. The sensitivity and specificity of this pre-enrichment strategy were validated in 100 paired pre-enriched saline gargle (PenSG) and OPS samples and 89 PenSG samples from healthy volunteers. In addition to detection of SARS-CoV-2, this pre-enrichment strategy may also be implemented in more clinical settings to optimize detection of other diseases.