Can Covid-19 spread when someone coughs through a mask? This is what the science says
- More research shows that while masks are effective at reducing infection risks, they are not the only measure you should take
- Coughing through a mask can aid the travelling of droplets that may contain the virus
- Researchers recommend new mask guidelines from regulatory bodies
By now, Covid-19 is synonymous with facemasks, and even though the use of facemasks was still questioned earlier on in the pandemic, the World Health Organization has updated its guidelines on masks since then.
Even though there is convincing literature to prove that a mask may reduce your risk of becoming infected with Covid-19 or infecting someone else, researchers have stated that face masks alone are not sufficient protection and can only be effective when paired with stringent hand hygiene and a distance of at least 2m between you and other people.
Now, research published in the journal Physics of Fluid showed that the filtering ability of a mask may be hampered by factors such as repeated coughing.
How often and how hard you cough may affect your mask
The research team from the University of Nicosia in Cyprus stated that while surgical, respiratory and fabric masks are now widely used among health workers and the general public to lower the risk of Covid-19 infection, it is still scientifically unclear to what extent these masks filter out the coronavirus that can be carried through respiratory droplets.
In previous research, the team determined that respiratory droplets can travel almost 5m in five seconds when a person coughs without a mask. They then wanted to use a model to determine to which extent coughing can affect the filtering abilities of a mask.
For this research, they used numerical simulations applied to a porous surgical mask.
Drops travel even when coughing with a mask
The new research determined that some droplets can travel as far as 1m during mild coughing. Although this is significant, a mask reduces the distance.
The size of the droplets produced when coughing can also play a role. "Masks decrease the droplet accumulation during repeated cough cycles," stated author Talib Dbouk in a news release.
"However, it remains unclear whether large droplets or small ones are more infectious."
According to the researchers, their projection for coughing was fairly conservative and they expect that the droplets can travel even further when a person coughs severely and frequently while wearing a mask.
Should masks be improved in the future?
While wearing a mask remains a vital measure in reducing infection risks, the study authors reiterate that we shouldn’t rely solely on masks, as a mask will never be able to provide complete protection from droplets, and that the distance droplets travel can depend on several changing factors, such as the frequency of the cough and how well your face mask fits.
Currently, there is no standardised regulation for the manufacturing of home-made, fabric masks, although the World Health Organization mapped out some guidelines in their updated recommendations.
The study authors, however, recommend that regulatory authorities should consider new criteria to judge the performance of a mask.
Hand hygiene, social distancing remains important
Study author Dimitris Drikakis said in the news release that physical distancing remains key to help reduce infections. He also states that healthcare workers should have much more advanced personal protective equipment such as helmets with built-in air filters, face sheets, disposable gowns and double sets of gloves.
The WHO also stresses that washing your hands, especially after coughing and touching your face, will help reduce the transmission of viral particles in droplets onto surfaces, which can then be spread to other people.
You should also wash your mask after every use and wash your hands before putting it on and removing it.