Stable "Salivary Viral Road Ratios" in Individuals Infected With Omicron Variants

Area of Science:

• Virology
• Infectious Diseases
• Public Health

Background:

• SARS-CoV-2 Omicron variants infect oral and salivary epithelia, leading to virus shedding in saliva.
• Aerosol transmission of cell-free virions in saliva droplets is a primary driver of COVID-19 spread.
• Temporal dynamics of cell-free virions in saliva are not well understood.

Purpose of the Study:

• To investigate temporal changes in cell-free virions shed into saliva relative to whole saliva.
• To analyze the salivary viral load ratio in individuals infected with SARS-CoV-2 Omicron variants.

Main Methods:

• Studied 14 subjects with SARS-CoV-2 Omicron variant infection on days 1, 4, and 7 post-symptom onset.
• Measured total viral load in whole saliva and cell-free virion load in centrifuged supernatant.
• Calculated the salivary viral load ratio (cell-free virions / total viruses).

Main Results:

• Viral load in whole saliva and supernatant decreased significantly over time.
• The salivary viral load ratio showed no substantial change across the observation period.
• This suggests consistent potential for aerosol transmission.

Conclusions:

• Chronological dynamics of salivary cell-free viral load and ratio are vital for monitoring aerosol transmission.
• Individuals with Omicron variant infections remain capable of aerosol transmission until recovery.
• The salivary viral load ratio can serve as an early indicator of aerosol transmission risk.