UK scientists begin study of how long Covid can survive in the air
It is the question scientists around the world are trying to answer: how long can the coronavirus survive in the tiny aerosol particles we exhale? In a high-security lab near Bristol, entered through a series of airlock doors, scientists may be weeks from finding out.
On Monday, they will start launching tiny droplets of live Sars-CoV-2 and levitating them between two electric rings to test how long the airborne virus remains infectious under different environmental conditions.
“It is a very important question,” said Prof Denis Doorly, an expert in fluid mechanics at Imperial College London, who is not involved in the research. “There is now huge interest in what it could take to mitigate the risk of infection in enclosed spaces, in terms of enhanced natural ventilation, or air-scrubbing systems, or UV-C lighting – but this all depends on knowing how much viable virus remains suspended in the air.”
Until now, it has been expected that Covid-19 is predominantly transmitted in respiratory droplets, produced when an infected person coughs, sneezes, sings, talks or breathes. These rapidly fall to the ground, providing the logic behind the 2-metre rule.
Yet among experts, there is a growing consensus that the virus may linger in smaller droplets called aerosols, which may be carried over greater distances in air currents and accumulate in poorly ventilated spaces.