Government advice to remain two metres apart from others may not be enough to protect people from contracting Covid-19 during windy weather, according to a new study.
Scientists who carried out the research, published in the journal Physics of Fluids, found that the risk of transmitting the coronavirus increases in the wind.
The study revealed that saliva droplets can travel further than usual upon even the lightest of winds. For example, in a breeze of only four kilometres per hour, they can travel up to 18 feet in only five seconds.
How height affects your risk
Explaining the different risk factors for someone’s exposure to such droplets, Professor Dimitris Drikakis, the author of the study and Vice President for Global Partnerships at the University of Nicosia in Cyprus, said, "Shorter adults and children could be at higher risk if they are located within the trajectory of the traveling saliva droplets."
What did the study involve?
The study aimed to understand how saliva moves through air, with researchers creating a simulation to examine droplets as they move away from a person coughing.
The model took into account variables such as dispersion force, interactions with air molecules, and humidity, as well as how the droplets evaporate.
Afterwards, the analysis of the model’s findings involved running differential equations on over a thousand saliva droplets. The study solved roughly 3.7 million of these equations, in total.
Co-author of the study, Professor Talib Dbouk, from the University of Nicosia, said, "Each cell holds information about variables like pressure, fluid velocity, temperature, droplet mass, droplet position, etcetera.
"The purpose of the mathematical modelling and simulation is to take into account all the real coupling or interaction mechanisms that may take place between the main bulk fluid flow and the saliva droplets, and between the saliva droplets themselves.
"This work is vital, because it concerns health and safety distance guidelines, advances the understanding of spreading and transmission of airborne diseases, and helps form precautionary measures based on scientific results."