Clinical Significance of a High SARS CoV 2 Viral Load in the Saliva
Background Patients with coronavirus disease 2019 (COVID 19) can unknowingly spread the virus to several people during the early subclinical period. Methods We evaluated the viral dynamics in various body fluid specimens, such as nasopharyngeal swab, oropharyngeal swab, saliva, sputum, and urine specimens, of two patients with COVID 19 from hospital day 1 to 9. Additional samples of the saliva were taken at 1 hour, 2 hours, and 4 hours after using a chlorhexidine mouthwash. The severe acute respiratory syndrome coronavirus 2 (SARS CoV 2) viral load was determined by real time reverse transcriptase polymerase chain reaction (rRT PCR) Results SARS CoV 2 was detected from all the five specimens of both patients by rRT PCR. The viral load was the highest in the nasopharynx (patient 1 8.41 log10 copies/mL; patient 2 7.49 log10 copies/mL) but it was also remarkably high in the saliva (patient 1 6.63 log10 copies/mL; patient 2 7.10 log10 copies/mL) SARS CoV 2 was detected up to hospital day 6 (illness day 9 for patient 2) from the saliva of both patients. The viral load in the saliva decreased transiently for 2 hours after using the chlorhexidine mouthwash. Conclusion SARS CoV 2 viral load was consistently high in the saliva; it was relatively higher than that in the oropharynx during the early stage of COVID 19. Chlorhexidine mouthwash was effective in reducing the SARS CoV 2 viral load in the saliva for a short term period.
Journal of Korean medical science