Finnish scientists have created a virtual environment similar to a grocery store to show how the saliva droplets of a person with Covid-19 can behave in the air.
Little is known about airborne transmission of the new coronavirus, which causes Covid-19 – and that is why social distancing is so important. It was precisely by looking for more clues about how these microorganisms spread in the air that four scientific organizations in Finland came together in search of an answer.
The researchers studied how the smallest particles that come out of our body when we cough, sneeze or even speak spread through the air. That’s because, according to the researchers, these droplets can carry Sars-CoV-2.
“Someone infected with the coronavirus may cough and walk away, but then leave behind extremely small aerosol particles carrying the coronavirus,” said Ville Vuorinen, assistant professor at Aalto University and co-author of the research, in a statement. “These particles could then end up in the respiratory tract of others in the vicinity.”
The team focused on studying a scenario in which a person coughs in a corridor between shelves, similar to a grocery store, taking into account the ventilation system that usually exists in these establishments. The model was also created based on the movement of aerosol particles smaller than 20 micrometers – previous studies indicate that, for a dry cough, the size of the particles is typically smaller than 15 micrometers.
Then, the result obtained surprised the team: the aerosol cloud spreads easily and takes a few minutes to be diluted in the air. This is because, according to the scientists, these extremely small particles do not fall to the ground, but move with the air currents or remain floating in the same place.
“The preliminary results obtained by the consortium highlight the importance of our recommendations. The Finnish Institute for Health and Welfare recommends that you stay at home if you are unwell and that you maintain physical distance with everyone,” said Jussi Sane, an infectious epidemiology specialist at the Finnish Institute for Health and Welfare.
If you need to leave your home, the authorities’ recommendation is to use masks (disposable or cloth masks). “The instructions also include coughing into your sleeve or a tissue and taking care of good hand hygiene,” noted Sane.
The researchers also used the model to create a video that shows the dissolution of saliva droplets in the air: