“The mask will not leave our routine anytime soon until there is an effective vaccine against covid-19”. The alert is from the doctor and preceptor of the medical residency and infectology internship at the Couto Maia Institute, Fernando Badaró, who only reinforces how much it will still be necessary to live with this indispensable accessory in times of pandemic.
With the relaxation of activities after social isolation, experts highlighted 14 types of facial coverage that can help reduce the risk of contamination, if used correctly and combined with hand hygiene with soap and water or gel alcohol (see below). Speaking of which, it is worth mentioning that the mask needs to cover the entire nose up to the chin. In addition, the fabric ones should be changed in a maximum of two to three hours of use or before that, if they get wet.
But a mask is not a vaccine nor does it eliminate the need for social distance. Wearing a mask is not a passport to gather around, as complements the Cidacs / Fiocruz epidemiologist and collaborator of Rede CoVida, Naiá Ortelan: “remember that we are still in a pandemic, that the SARS-CoV-2 has undergone changes . Always reflect on whether, in fact, this exposure is really necessary. And if it is, go with a mask ”.
1. Cloth masks They are the easiest to find and also the most practical. “Whenever you want to leave home, take two or three of them. Every two hours, make the change and keep the dirty in a bag inside the bag. A constant mistake is leaving this mask on your chin, which ends up exposing you to the risk of infection ”, recommends the infectologist at Hospital da Bahia and professor at Unifacs, Juliana Correia.
Fabric masks are the most common and should be changed every two or three hours
2. Disposable surgical masks These must be discarded immediately after use. “You can use a maximum of 6 hours. They are efficient. As they have a lateral opening, the ideal is to maintain a distance ”, explains the director of the Brazilian Society of Infectious Diseases (SBI), Antônio Bandeira.
3. Polypropylene and cotton masks Polypropylene is placed between two layers of cotton, as stated by epidemiologist Naiá Ortelan. “They are able to reduce droplet transmission by 90% or more, compared to the absence of facial coverage.”
4. N-95 Infectologist Juliana Correia points out that the N-95 is the one that guarantees the greatest seal, however, it is recommended to be used by health professionals. “In addition to protecting from droplets, it also protects from aerosols, which are smaller particles that are suspended in the air of speech, coughing and sneezing, so they can contain viruses and bacteria.”
Disposable masks can be used for up to six hours
5. Bandanas The epidemiologist Naiá Ortelan points out that, according to a recent survey, the protection of bandanas made of scarves and used as a mask was only 5%. “In the study’s ranking, the bandanas occupied the penultimate position, second only to the neck collar used as a mask”.
6. Triple layer masks For the director of SBI, Antônio Bandeira, the ideal is that the fabric masks have three layers: “that is, two of cotton and one of a fabric that can be on the outside”, he adds.
7. Hybrid fabric masks The hybrid fabric, formed by combining cotton with polypropylene and polyester has excellent droplet filtration capacity. However, the epidemiologist Naiá Ortelan calls attention to the issue of comfort: “depending on the activity performed, it can cause a greater sensation of shortness of breath and heating in the face”.
The N-95 is the one that guarantees greater sealing
8. Fabric masks with reusable filter What needs to be observed is the porosity of the tissue of this filter, as indicated by the doctor and preceptor of the medical residency and internship in infectology at the Couto Maia Institute, Fernando Badaró. “The ideal is to use fabrics with a more closed mesh”, he says.
9. Polyester mask Epidemiologist Naiá Ortelan reinforces that, to date, there is no evidence on the effectiveness of this type of mask. “If this mask has at least two layers and the weave is tightly closed, it is likely to be efficient. On the other hand, it must be evaluated if it does not bring a greater feeling of warmth to the face ”.
10. Antivirals / block viruses These are masks that, according to infectious disease specialist Fernando Badaró, still do not have enough research. “The right thing is to use a mask that protects, that has two to three layers. Effectively proven, only NR-95 is guaranteed to have the most complete protection against particles and aerosols ”.
The greater the number of layers, the better. The mask must cover the entire nose to the chin
11. Double layer masks The fabric masks can not last more than 2 hours, especially if they are double layer masks, as the infectologist Juliana Correia advises. “The smaller the number of layers, the lower the efficiency. The World Health Organization (WHO) advises that the mask has two or three layers of cotton and a tightly knitted fabric ”.
12. Zero sewing / masks off It also depends on the number of layers, insists the infectologist Fernando Badaró. What needs to be observed in the off mask is how the protection is when the fabric is stretched. “If this mask has several layers of protection, it is effective. Mainly, because it is a mesh that stretches it cannot have a single barrier ”.
13. Homemade masks with perfex Perfex (multipurpose cloth usually used to clean the kitchen) is porous and does not protect. For this reason, it is not recommended by the infectologist Fernando Badaró. “It doesn’t fit. Prefer cotton and remember that the mask cannot be transparent. The layers of protection are fundamental ”.
14. Masks with UV protection They guarantee this protection as long as the fabric is able to prevent the passage of light. “It is necessary to observe whether the fabric that the mask was made on even with this UV technology plus the presence of layers”, considers infectious disease specialist Fernando Badaró.