This archive report was first published on 14 May 2020.
Published on May 14, 2020, a study by researchers at the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) shed light on the spread of Covid-19 through speech.
Researchers had a person loudly repeat the phrase 'Stay healthy' for 25 seconds inside a closed box, generating microdroplets that were illuminated by a laser and counted.
The study found that these microdroplets stayed in the air for an average of 12 minutes, with scientists estimating that each minute of loudly speaking can generate over 1,000 virus-containing droplets capable of remaining airborne for eight minutes or more in a closed space.
According to the researchers, 'this direct visualisation demonstrates how normal speech generates airborne droplets that can remain suspended for tens of minutes or longer and are eminently capable of transmitting disease in confined spaces.'
The study's findings could have significant implications for public health recommendations, particularly in regards to the use of face masks to prevent the spread of Covid-19.
