These protective shields look more comfortable than face masks. Without a doubt, by not being in direct contact with the nose and mouth, it makes it easier to breathe, speak and something else, they give less heat.
Here arises the next unknown.-⇾ Do they protect us to the same extent as a facial mask? Can we really replace one with the other?
According to an opinion piece recently published in the Journal of the American Medical Association, these displays have a number of advantages. They are comfortable to use, protect entry portals from the virus and reduce the potential for self-inoculation, as they prevent the user from touching their face, says the text prepared by Dr. Eli Perencevich, specialist in infectious diseases at the University of Iowa, and two other researchers. Another advantage, unlike face masks, they do not need to be removed to facilitate communication, they can be reused indefinitely if they are not damaged, and they can be easily cleaned with soap and water or common disinfectants, the article points out. Although the article states that the authors do not advocate the use of this screen as the only measure, but they do consider that it can be one more element in a coronavirus containment strategy that includes hand washing and social distance among other things. In the same vein, a cough simulation study from 2014, a good plastic screen can reduce total exposure to cough droplets and aerosols by 96% at a distance of 46 cm. But, with the smaller aerosols, the shield was less effective, blocking 68% immediately after exposure to cough, and only 23% in the next 30 minutes, as these smaller aerosols can be left floating under the visor, in the space where inhalation occurs. According to Julian Tang, professor in the Department of Respiratory Sciences at the University of Leicester, in the United Kingdom, face shields are generally quite effective, but he acknowledges that comparing them directly with surgical masks is difficult, and that the studies that have been done so far they have only succeeded in a limited way. According to your recommendation. If we are going to use them, the most important thing to take into account is “how far the protector curves to cover the ears (if there is a gap, the aerosols could enter this way and cause an infection) and how far it extends underneath (to protect ourselves from the floating aerosols that we can inhale under the shield) “, Tang tells BBC World. Another factor to take into account is that there is no gap in the upper part, where the visor rests on the forehead, to reduce the risk of exposure to drops or aerosols that may fall from above.
Another opinion on this topic.
Aaron Glatt, director of the department of medicine at Mount Sinai South Nassau Hospital, in the United States, believes that the benefits of screens vary depending on who uses them. It is recommended for use in the case of a health worker, for example, who must enter the room of a patient who has or is suspected of having COVID-19 and is not wearing a mask, he tells BBC World. In this case, the potential for the patient to shed virus particles is great and it is important to protect the eyes of the healthcare worker with glasses or a face shield, over the mask. But in a community context, the mask (and not the screen) is recommended, because it is more effective in preventing the virus from spreading to the surrounding areas. The Centers for Disease Control and Prevention (CDC) also does not recommend its use in the context of everyday life or as a substitute for cloth masks. But in case someone decides to use it without a mask underneath, they need to make sure that it covers the sides of the face and extends below the chin. Another thing, the World Health Organization (WHO) recently recognized, in response to an open letter published by more than 200 scientists, that there is increasing evidence that the coronavirus can be spread by these tiny airborne particles. Airborne transmission cannot be ruled out in crowded settings or in closed and poorly ventilated places.
However, this transmission route, explains Luis Ostrosky, professor of infectious diseases at the McGovern School of Medicine at UTHealth in Houston, USA, is not the main one. The primary transmission route for Covid-19 is believed to be through droplets, so there are two ways to protect yourself from them: one is by covering your mouth and nose with a mask, but that leaves the rest of your face uncovered. The other is with a face shield, which covers your entire face, says Ostrosky. In Ostrosky’s opinion, they are particularly beneficial for young children, as they reveal facial expressions. They are believed to be a key element in the reopening of the schools. The WHO, for its part, points out that, for the public, screens can be considered as an alternative in the event that there is a shortage of non-medical masks, but says they are inferior to masks with respect to the prevention of droplet transmission.
In short, we invite you to take care of yourself and take alternative improvements to protect us from this terrible disease. Team Boett