Linsey Marr weighs in on possibilities of COVID-19 transmission

Linsey Marr, the Charles P. Lunsford professor in the Charles E. Via Jr. Department of Civil and Environmental Engineering, does research on the emissions, fate, and transport of air pollutants in order to provide the scientific basis for improving air quality and health.  

“I’m passionate about doing research to protect human and environmental health and reduce threats to public health,” said Marr.

Marr began studying the airborne transmission of infectious diseases after her growing frustration watching her young children frequently catch infectious diseases from their peers at daycare. She studies factors that affect infectious disease transmission including humidity and the length of time that viruses survive in the air and on surface.

While her research primarily focuses on flu transmission, many of the concepts from her research can potentially be applied to the spread of COVID-19.

While most respiratory viruses decay rapidly when humidity is above 40%, there is not enough research about how this virus behaves to know whether increased humidity will have any effect on transmission. However, public health officials have given some hope by saying that Coronavirus is not airborne. In a recent New York Times article titled “How Long will Coronavirus Live on Surfaces or in the Air Around You?,” Marr argues that this is a difficult assumption to make as coughs, sneezes, and breaths can potentially transmit viruses through aerosols, which are smaller than droplets and may remain afloat for longer distances. “Airborne viruses will eventually settle on surfaces and can be picked up by someone who touches them,” she said. “The ability to survive varies with temperature, humidity, and surface material.” She noted that viruses in small droplets can float around in air for many hours, but they will likely be diluted unless you’re in a small, confined space. The concentration of airborne viruses is quite high at close range, but the concentration falls off rapidly as an individual gets farther from the source.

This is why Virginia Tech and the Commonwealth of Virginia have put limitations on large gatherings in confined spaces. To see Virginia Tech’s announcement, click here.

While there are many assumptions that can be made based on other viruses, many of them are just assumptions. “I wish we knew more,” said Marr.