Do face masks really protect against the spread of Covid-19?

Face masks became common place since the outbreak of Coronavirus, following the belief that face coverings provide protection against the spread and acquisition of Covid-19. The Centres for Disease Control and Prevention -the leading national public health institute of the United States- explains that covering face and mouth in public places is essential during this pandemic. In some countries, wearing a face mask in public places is even mandatory, but are they really effective?

The correct answer is: it depends. It depends on which type of mask you wear.

Assosistema Safety, the trade association of Confindustria (Italy), has studied the effectiveness of face masks since the Coronavirus outbreak.

A woman wearing mask (Representational Image). Image credit India.com

A position paper of the trade association explains that the first step to take is distinguishing respiratory protection masks from surgical or anti-smog masks. “Surgical masks are medical devices created to protect the patient in specific situations -for example during surgeries- and not the healthcare personnel, and therefore they are of little use because they were not designed to defend the wearer from the virus’ molecules.”

“The recommended filter masks are FFP2 and FFP3 which have a filtering efficiency of 92% and 98%”, explains Dr Spasciani, Vice President of Assosistema Safety. The trade association states that in the case of Coronavirus, the World Health Organization itself prescribes a device compliant with “EN 149” standard with a valid CE pattern followed by the number of the Control Body that authorizes its marketing. The masks compliant with the corresponding European standard “UNI EN 149:2009” are also suitable to protect from viruses. They are also recognized by international institutions such as WHO and the US National Institute for Occupational Safety and Health (NIOSH).

However, Assosistema Safety’s position paper warns about the importance of wearing the mask correctly. Following the WHO basic instructions for wearing the masks, you firstly need to clean your hands with an alcohol-based disinfectant or with soap and water. When covering your mouth and nose, it is crucial to ensure your entire nose and mouth are covered, meaning that the face mask should fit underneath your chin - the covering will be less effective if you remove it from your face to speak to someone, so it is recommended to adjust your mask before entering a crowded place.

It is also advised not to touch the face mask while using it. Eventually, always substitute the mask with a new one as soon as it gets wet and do not reuse disposable ones. It is also advised, when removing the bezel, to do so from behind without touching the front of the mask. And after removing it, immediately throw it in a closed container, accurately cleaning your hands afterwards.

And what about homemade face masks? Research explains that nonmedical masks are not considered as effective at blocking small particles as the N95 face masks, but homemade face masks are easily and quickly available, and still can block the larger particles emitted when talking, coughing, spitting and sneezing.

To this regard, the Centre for Disease Control and Prevention (CDC) - the leading national public health institute in the United States- recommend medical-grade face masks for people who were presumed to have Covid-19, but for health workers too.

Woman protecting against Covid-19 droplets, Image credit Vector illustration

As recent research demonstrated, the virus can live in droplets in the air for up to one to three hours after an infected individual has left a place. Therefore, covering the face is essential to prevent these droplets from getting into the air and infecting other individuals.

Using a cloth to cover your face when you are around others can help block large particles that you might eject as well, slowing the spread of transmission to others “in case you are an asymptomatic carrier of the coronavirus”, the American Lung Association affirms.

Lastly, be aware that there is no wide scientific evidence that the masks will conform to the face tightly enough to form a seal, or that the filter material inside will work effectively. For instance, standard surgical masks are known to leave gaps, that is why the CDC emphasizes other precautions in addition to covering your face, like washing your hands and distancing yourself from others.