Are we really ready to say goodbye to masks?

Masks outdoors, indoors. In the workplace, in means of transport, at school. In these days, the government, after consulting with the technicians of the Ministry of Health and with those of the control room of the Covid-19 emergency management, will decide if and how to update the rules on the use of masks. The update should enter into force starting from May 1st, and according to the first rumors the line would still be that of the utmost prudence: therefore protections still to be worn in public transport and in the workplace. Still in doubt, however, the rules regarding cinemas, theaters, shops, supermarkets and restaurants. While waiting to hear about the government's decision, here is a summary of what you need to know about the issue.

What the rules say today This is the situation at the moment. On March 31, after two years, the epidemiological emergency due to the pandemic from Covid-19 ended, and the government presented a new decree that contains the post-emergency rules, especially relating to the display of the green pass, which does not it is most in demand to access outdoor dining activities, outdoor sports activities and to use local public transport. For masks, however, as already mentioned, there is still a few days to wait: until 30 April it will therefore still be necessary to always wear them in all indoor places.

Scientific evidence The evidence of the efficacy of masks to stem infections is now quite solid, even if the answer to the question varies according to many factors: which type, in what context they are used, if they are worn correctly . The largest study ever conducted on the subject so far, which involved over 300 thousand people in Bangladesh and was published in the Innovation for Poverty Action Working paper magazine, confirmed that surgical masks are effective in combating the infection from Covid-19, especially if combined with social distancing and other pandemic containment rules. To understand this, the authors of the work - belonging to Yale University and other research institutes - first of all involved 340 thousand Bengalis with the aim of promoting the use of masks and making them more accessible, to understand if targeted information interventions could increase the '' adherence to the protective measure: the volunteers, therefore, were divided into two large groups, of which only the first received free masks (surgical or cloth, all made of three layers) and repeated information, during the trial, on the importance of their use and on how to wear them correctly. In addition to assessing compliance with the measures, the researchers also monitored the health of the volunteers, detecting any symptoms and periodically carrying out tests for the presence of anti Sars-CoV-2 antibodies. Crossing the data collected, and putting them together with those on the prevalence of the disease during the observation period, the scientists finally noticed that communication interventions actually work (in the "informed" group the use of masks has tripled) and above all that the surgical masks are effective: the villages that had received them recorded a decrease in infections of 11%, with a particularly favorable outcome in the over 60s (-35% of infections). The speech is not true, however, for cloth masks, the use of which is associated with a much more modest decline in infections.

Which type to choose? So let's see what are the various types of masks currently available, and on which one should be oriented. The most filtering of all are the N95, or Ffp2, which, when worn correctly, are able to block about 94% of the particles suspended in the air; they also have tangled fibers that act as an additional filter for airborne pathogens. Immediately after, there are the Ffp1, which, for the same use, provide coverage of about 80%, and then the surgical masks, less filtering but, as we have just seen, quite effective if used correctly. The surgical masks are composed of 3 or more layers of porous material, of non-woven fabric, and are able to filter both the droplets of saliva larger than 5 micrometers transmitted when coughing or talking and the smaller ones, the so-called aerosol, smaller than 5 micrometers in size. Finally, there are the "homemade" or two-layer masks, including those made of cotton or cloth, which however are less effective than the others.