Detection of SARS-associated Coronavirus in Throat Wash and Saliva in Early Diagnosis

Abstract

The severe acute respiratory syndrome–associated coronavirus (SARS-CoV) is thought to be transmitted primarily through dispersal of droplets, but little is known about the load of SARS-CoV in oral droplets. We examined oral specimens, including throat wash and saliva, and found large amounts of SARS-CoV RNA in both throat wash (9.58 x 102 to 5.93 x 106 copies/mL) and saliva (7.08 x 103 to 6.38 x 108 copies/mL) from all specimens of 17 consecutive probable SARS case-patients, supporting the possibility of transmission through oral droplets. Immunofluorescence study showed replication of SARS-CoV in the cells derived from throat wash, demonstrating the possibility of developing a convenient antigen detection assay. This finding, with the high detection rate a median of 4 days after disease onset and before the development of lung lesions in four cases, suggests that throat wash and saliva should be included in sample collection guidelines for SARS diagnosis.

Keywords

• severe acute respiratory syndrome
• SARS
• coronavirus
• CoV
• Taiwan
• perspective