A new survey has found more evidence to suggest that people can become infected with COVID-19 through aerosol transmission, which could be prevented by wearing a mask.
Carried out by data scientists in the UK, Norway, and the US, the study is one of the first to investigate which personal and work-related factors can lead to COVID-19 transmission.
After surveying 2,000 people in the UK and US, the researchers found that the data from both countries suggests that aerosol transmission of the virus — via microdroplets which are so small that they remain suspended in the air for several hours — is very likely.
Moreover, they say that taller individuals appear to be at a higher risk. Individuals over 6ft tall seem to have more than double the chance of having a COVID-19 medical diagnosis or testing positive. The researchers said this suggests that aerosol transmission is very likely, as if COVID-19 transmission was solely due to droplets, which are bigger than aerosols and are thought to travel relatively short distances and drop quickly from the air, taller individuals would not be at higher risk. In contrast, aerosols can accumulate in poorly ventilated spaces and are carried by air currents.
The findings were posted on the preprint website medrxiv.org, and have not yet been peer-reviewed, meaning that they haven’t been verified by experts. However, with the recent debate over whether aerosol transmission is possible, the researchers said that they wanted to make their results available now.
Another finding from the study is that using a shared kitchen or accommodation, which may be linked to a lower social status, is a significant factor in transmission; in the US people using these shared spaces had a 3.5 times higher risk of being infected, and in the UK the risk was 1.7 times higher.
Professor Evan Kontopantelis from the University of Manchester commented, “The results of this survey in terms of associations between height and diagnosis suggest downward droplet transmission is not the only transmission mechanism and aerosol transmission is possible.”
“This has been suggested by other studies but our method of confirmation is novel. Though social distancing is still important because transmission by droplets is still likely to occur, it does suggest that mask wearing may be just as if not more effective in prevention. But also, air purification in interior spaces should be further explored.”