What's in the Air? CSD Researchers Leading Study to Learn More about How COVID-19 Spreads

by Hannah Rae Vaden

Are you wearing your mask? Dr. Miriam van Mersbergen, director of the Voice, Emotion, and Cognition Laboratory in the School of Communication Sciences & Disorders, and her colleagues want to know what is in the air. Dr. van Mersbergen is a co-investigator in a multi-disciplinary study of aerosolization through a cross-institutional grant involving researchers at the University of Memphis (UofM) and the University of Tennessee Health Science Center (UTHSC). Researchers working on the aerosolization project include otolaryngologists, biomedical engineers, and speech-language pathologists, including our alumna Amy Nabors.

The primary goal of the study is to understand the biological mechanisms behind disease particle aerosolization so that public health measures can be developed to limit the spread of airborne diseases, like COVID-19. Researchers theorize that COVID-19 particles may cling to aerosolized saliva as it leaves your mouth during speech and other daily vocalizations. Speech tasks can create as much particulate transmission as coughing. Furthermore, some people emit many more particles than others as they vocalize, so they might be more likely to spread airborne disease than others.

Motivated to understand why singers were infected with COVID-19 early in the pandemic, Dr. van Mersbergen is interested in the biological differences that determine how much particulate matter individuals aerosolize as they speak and sing. Her study also examines what types of vocalizations emit aerosolized materials. Air quality and ventilation might also contribute to higher infection rates. Dr. van Mersbergen hopes to find ways to reduce the amount of particulate matter that people release during vocalizations.

Capturing images of aerosolization depends on the expertise of the interdisciplinary team. The researchers use a high-quality laser to illuminate the particulates that participants emit as they complete different kinds of vocalizations. A high-speed camera photographs the particles illuminated in the air as they travel. This allows researchers to see the size and quantity of particulates released during different speech tasks. Factors such as anatomical differences, gender, and language spoken may be linked to the quantity of particles a person emits during vocalization, which can further inform safety measures to prevent disease transmission. This study is unique and will likely yield a lot of valuable information about disease contagion control. In the meantime, keep wearing those masks!