Clinical Significance of a High SARS-CoV-2 Viral Load in the Saliva
Jin Gu Yoon, Jung Yoon, Joon Young Song, Soo Young Yoon, Chae Seung Lim, Hye Seong, Ji Yun Noh, Hee Jin Cheong, Woo Joo Kim, Jin Gu Yoon, Jung Yoon, Joon Young Song, Soo Young Yoon, Chae Seung Lim, Hye Seong, Ji Yun Noh, Hee Jin Cheong, Woo Joo Kim
Abstract
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.
Keywords: COVID-19; Chlorhexidine; SARS-CoV-2; Saliva; Viral Load.
Conflict of interest statement
The authors have no potential conflicts of interest to disclose.
© 2020 The Korean Academy of Medical Sciences.
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Source: PubMed