Particulate matter (PM_2.5) as a potential SARS-CoV-2 carrier

Area of Science:

• Environmental Science
• Infectious Disease Epidemiology
• Aerosol Science

Background:

• The COVID-19 pandemic highlighted the need to understand SARS-CoV-2 transmission routes.
• While respiratory droplets were initially considered the primary mode, indirect transmission via fomites and aerosols became a concern.
• The role of specific airborne particles in virus transport required further investigation.

Purpose of the Study:

• To investigate the potential of fine indoor air particulates (PM2.5) as a transport medium for SARS-CoV-2.
• To determine the correlation between SARS-CoV-2 RNA on PM2.5 and hospital ward characteristics.
• To explore the influence of patient factors on airborne virus concentration.

Main Methods:

• Collection of PM2.5 samples over four weeks in four hospital wards with varying COVID-19 patient clusters.
• Utilized 48-hour measurement intervals for comprehensive air particulate analysis.
• Quantified SARS-CoV-2 RNA presence on collected PM2.5 samples.

Main Results:

• SARS-CoV-2 RNA was detected on indoor air PM2.5 samples.
• The highest concentrations of virus-laden PM2.5 were observed in wards with a greater number of occupants.
• A correlation was suggested between virus-laden PM2.5 and hospital ward design.

Conclusions:

• Fine indoor air particulates (PM2.5) can act as a transport agent for SARS-CoV-2.
• Hospital ward occupancy and design appear to influence airborne SARS-CoV-2 RNA levels on PM2.5.
• Patient symptoms and numbers are significant factors affecting airborne virus concentration in enclosed spaces.