Superspreading : How it works

Published Oct 29, 2020

Share

CAPE TOWN - Scientists look into the airborne transmission of Covid-19 discovering a wide variety between individuals and the way they emit infectious aerosols.

In 2003, Lidia Morawska, a physicist at the Queensland University of Technology, joined a team of researchers in Hong Kong aiming to understand the way in which SARS spreads, with Morawska adopting an unconventional approach to her research focusing on the exhalation of infectious particles.

“I found three papers investigating anything to do with exhalation of particles from human respiratory activities. There was basically next to nothing,” Morawska said the National Geographic. “This amazed me because this is such an important area, such a critical area.”

When the outbreak of Covid-19 took place in late 2019, this sparked further research in the way contagious particles could be emitted with scientists looking to understand the way in which Covid-19 was spread with varying focuses on possible transmission with airborne transmission being one of the last confirmed discoveries.

In efforts to find the answers to superspreader or superemitter events where a few individuals were able to infect large numbers of individuals, scientists looked to further understand the way in which aerosols were formed in the body to determine what makes certain individuals this capable of spreading viruses finding many factors attributing such as the shape of an individuals body, certain behaviours such as breathing fast or loud talking.

”They're not sneezing. They're not coughing. They're just breathing and talking,” says Donald Milton, an aerosol transmission expert from the University of Maryland. “They might be shouting. They might be singing. Karaoke bars have been a big source of superspreading events. We saw one at a spin cycle club up in Hamilton, Ontario, where people are breathing hard.”

Although there are many factors that need to be considered in this form of transmission such as the environment, air humidity, temperature and airflow, these tiny contagious droplets come in all sizes, however the ones that cannot be seen by the naked eye may be the most dangerous.

“The smallest aerosols are generated in the deeper part of the respiratory tract,” Morawska says. These droplets go unseen to the human eye and can be suspended into the air for minutes to hours allowing them to also travel further.

A way to reduce the risk of airborne transmission is something as simple as the proper use of face masks and maintaining safe physical distancing in spaces with proper ventilation.

For LIVE updates on the Coronavirus pandemic, follow us on Twitter: @sacoronamonitor

CORONAVIRUS MONITOR

Related Topics:

Covid-19