QCOSTARICA – Masks have been a part of our daily lives since the middle of 2020. It’s unheard of it today to go out or be around people without a mask. However, the best ways to use them to make them more effective remain under constant study.
Given the appearance of more contagious variants of the virus that produces covid-19, scientists are analyzing more efficient and safer ways to use the mask.
In the United States, the Centers for Disease Control and Prevention (CDC), indicates that there would be more protection if you use a surgical mask and, on top of it, a three-layer fabric mask.
Some European countries, like Norway, are considering this possibility. In Spain, health authorities raised their quality requirements for masks.
What should we do in Costa Rica?
Former Minister of Health and pediatric infectologist specialist, Dr. María Luisa Ávila, considers that, given the current conditions of the disease in our country, it is not necessary to use two masks.
“The recommendation for the United States is very initial and is for certain circumstances. They are at a very different time of the pandemic than we are,” she said.
At this time, our country has a low registry of infections. The number of new daily cases of infection is on average half of what at the beginning of the year and the R rate has been down for four weeks, according to both the Universidad Hispanoamericana and the Centroamericano de Poblacion of the Universidad de Costa Rica.
For Ávila, the most important thing is to wear a single mask correctly.
“You can use five masks, which if you do not use them well will not protect you”, clarified the doctor.
Constant review
The first evidence, at the beginning of the pandemic, pointed out that the masks meant that if a person carrying the virus without knowing it, they could not infect someone else, and, if they did, the symptoms were weaker because the amount of virus entering the person would be less.
Later studies pointed out that these devices would possibly also protect a healthy individual from infection.
Of course, to achieve its mission, fabric or reusable masks must have at least three layers and surgical ones can only be used once and then discarded.
However, the best mask is useless if the person does not know how to use it well.
“You have to wear masks, but not only that; to know how to use it, and to know that this does not replace hand washing or physical distancing,” emphasized Lizbeth Salazar, dean of the Faculty of Medicine of the University of Costa Rica (UCR).
“Masks not only prevent saliva from reaching people directly, they also prevent us from depositing it on surfaces such as tables, where people can directly touch the virus and then put their hands to their faces,” she added.
Salazar gives an example: if it rains and we don’t have an umbrella and we try to cover our heads with a handkerchief, we are going to get wet, if we use two handkerchiefs, the difference will not be much, because the second handkerchief will get wet and we will get wet. But if we use a single umbrella or a single waterproof layer, our head will be much more protected.
In other words, it is not a matter of quantity but of quality. Therefore, the three layers of a mask are essential.
Where does the recommendation for two masks come from?
Today, science is focused on seeing ways that the mask can protect us more against a virus that could become increasingly elusive.
A simulation study conducted during the month of January by the CDC and released this Wednesday studied the effectiveness of masks in three circumstances.
- A three-layer surgical mask, without adjusting.
-
A surgical mask adjusted to the face, for this, a knot is made in the strips at the end of these, when reaching the “solid” part of the mask. This ensures not allowing the passage of air.
-
Combining a three-layer cloth mask that is used over a disposable or surgical one. The cloth mask should press down on the disposable so that it “fixes” it on the skin.
Two experiments were done. Both used a prototype of a flexible human head. Through a mouthpiece, the human mouth and its normal movements were simulated.
In the first experiment, coughing was simulated and how saliva droplets and aerosols (smaller droplets that remain suspended in the air) traveled.
The researchers found that a no-fit surgical mask blocked 42% of the simulated cough particles.
The cloth mask blocked 44.3% of the particles and the combination of both masks blocked 92.5%.
In the second experiment droplets and aerosols were measured in normal interactions, such as talking or breathing, whether the person emitting the aerosols was wearing a mask and another person nearby was not.
It was also analyzed what happened when the person who emitted the aerosols did not have a mask on and the other person did. And, finally, what happened when both people had a mask was observed.
In this case, it was determined that adjusting the disposable mask filtered 82.2% of the aerosols when the person who emitted the aerosols was wearing two masks and another person was not, and blocked 64.5% if they had one. mask attached.
On the other hand, if the aerosols come from a person without a mask and there is a person with a mask nearby, 64.5% leaked with a tight-fitting mask and 83% with a double mask.
If both users had the mask attached, the aerosols stopped emitting in 95.9% and with double mask, in 96.4%.
Ávila explained that, as N95 respirators are scarce, in medical centers there are personnel who use a mask over them to extend their useful life, but not to have greater protection.
“But in other circumstances, you will see that in hospitals we only use a mask,” emphasized the pediatrician.
How to better protect yourself
There are tips that you can follow to improve the effectiveness of this protection against covid-19.
The first is to make sure the mask covers your nose, mouth, and your entire chin. In addition, it is vital that it is well fixed and does not move.
“I have seen people who‘ cross ’the strips on their ears, so that they form an X. The problem with this is that you may feel it more fixed on your nose, but hollows are made in the cheeks and through there the air can pass. That gives a false sense of security,” Ávila highlighted.
If these devices are too large for you, it is advisable not to cross the strips, but to have them custom-made or buy adjusters so that they are fixed.
Now, there is a possibility in which it is better to use two of these protective implements: when it does not have all three layers, and, on the contrary, it has only one or two. However, it is preferable to use only one of three layers.
