There has been much debate on how to stop the covid-19 virus effectively. Various theories have been propounded, from herd immunity to the use of masks. When the virus first took over the world, it was said that masks and respiratory gears are mostly needed for public health officials. However, WHO has now shifted its guidelines emphasizing that everybody needs to wear face masks.
Even with the mass rolling out of vaccines, the guidelines for mask use have remained in place. As a result, there is much to unpack about how effective the masks are and the new evidence that has surfaced in support of mandatory masks. Also important are the implications of abstaining from mask usage, which health officials have called a ‘foolhardy’ decision.
How is the virus transmitted in our people to people interactions?
People fall under a pertinent risk of contracting the virus when they come inside a six-foot radius of another person who is covid-19 positive. When this happens, a person can directly inhale the air droplets containing the SARS-CoV-2 (exhaled by the carrier). This can only happen if they are standing close by to another covid positive person.
How does the air-borne transmission work?
The second way by which we can contract the virus is called airborne transmission. It happens when the air droplets containing the virus linger on in the air for some time, ranging from minutes to hours. Therefore, a person can contract the virus even though they did not come in close contact with a carrier. This type of transmission has a higher risk of occurring in areas with poor ventilation. Nonetheless, research shows that airborne transmission is a much rarer phenomenon than transmission via close contact.
Over time most of the virus within the air droplets die out as the virus needs a source of energy to generate its copies. The virus contains the RNA strands on which the codes for its replication are written. But, it lacks the energy resources and other tools required to replicate its copies. Hence, it has a constant need for hosts like humans and other animals.
Moreover, it has also been found that speech can also be a key contributor to viral transmission. Previously, it was thought that the virus mainly transmits when a carrier sneezes or coughs. However, recent findings have held speaking more culpable for viral transmissions and the higher the volume of the speech. The more the air droplets exhaled and hence higher the chances of getting the virus into the air.
The size of air droplets can range from five micrometers at minimum to ten micrometers at maximum. But the heavier particles usually fall on the earth’s surface due to gravity pulling on them.
How masks prevent transmission?
A plethora of epidemiological and laboratory setting studies have conclusively shown the effectiveness of masks in preventing inhaling air particles containing the virus.
In one study, it was found that the most effective usage of masks is as a ‘source control.’ This means that most of the droplets that come out of our mouths are further broken down into even smaller aerosolized particles by the process of evaporation. These tiny particles last suspended in the air indefinitely. Hence masks shall be used to prevent the formation of air droplets because the droplets can not pass through the weaves of masks.
Mask usage has only been found particularly useful in fighting against the coronavirus. This paper shows that in a sample of ten participants, the masks were only useful in blocking droplets containing the coronavirus. Furthermore, the masks were not found even remotely useful in blocking rhinovirus and influenza air droplets.
A laboratory setup experiment was conducted to show the masks prevent the generation of micro-sized air droplets. The experiment was titled Laser Light-Scattering Experiment Showing Speech-Generated Droplets. The results of the study were published in The New England Journal of Medicine. The results established that when a person said a simple phrase such as Stay healthy. And many droplets were generated whose size ranged between 20 to 500 μm.
The same research also confirmed that the droplets increase in size when our speech gets louder. Similarly, the size of droplets produced when we cough or sneeze is greater than that produced by speech. In addition, the researchers found that almost all the droplets were stopped after the speaker’s mouth was covered with a damp cloth.
Mask used in high-risk situations
Mask usage has been found effective in all scenarios. Even within a hospital full of covid positive patients. Researchers found that in three Chinese hospitals, medical staff that wore masks around covid patients did not contract the virus. Their peers, however, got the virus even though they did not operate in the quarantine wards.
Another case found a man who tested positive after flying from China to Toronto. The man was wearing a mask during his flight. So, when those sitting closest to him and the flight attendants were tested, their results came out negative.
How to deal with Asymptomatic and pre-symptomatic carriers?
Asymptomatic carriers are those who do not show any symptoms of their covid illness. Similarly, pre-symptomatic carriers are the ones who have yet to show the symptoms of their illness. However, both of these cases are the same in that they can be silent carriers of the virus.
Traditional ways of dealing with these kinds of covid carriers are futile. Therefore, quarantining is only recommended after establishing that a person is covid positive without any symptoms that become difficult to establish. So one of the ways to go around this anomaly might be mass testing. Still, wearing masks might be our best bet against carriers who show no symptoms, as mass testing entails consuming important resources.
This research paper has dubbed the asymptomatic covid spread as the “Achilles’ heel of current strategies to control covid-19,” as, without symptoms, we are essentially blockaded from identifying the carriers. That’s why public health officials have posited that wearing masks is the best way to bring the virus under control.
Stats on mask use and covid prevention
There has been plenty of research into establishing mask usage as a beneficial step for the entire citizenry of a country. A research paper published by Health Affairs outlined its findings on how a mandated use of face masks was helping in combating the ever-increasing rate of covid-19. The study found that across the fifteen states plus Washington D.C, the number of cases went down significantly when the use of masks was mandated.
After five days, the cases had gone down by 0.9 points compared to the five days before the mandate was not enforced. Similarly, after three weeks, the number of patients who had tested positive reduced by two percentage points.
An observational study was published on how the secondary transmissions in households across Beijing have been curtailed due to mandatory mask use. A cohort study in which a single person who had tested positive for covid-19 was chosen from 124 families. It was found that using a face mask was 79 percent effective in reducing secondary transmissions.
Countless studies have provided us with results that make an ample case for using face masks. For instance, this study, published on arXiv, says that if 80 percent of the population starts wearing masks, then the overall tide of the coronavirus can be set back. Thus, face masks can act as a crucial bulwark against the covid-19 virus is a well-established fact now.
Which face mask should be used?
The conventional wisdom should always be that the N-95 masks. Furthermore, the protective gear should be reserved for public health officials and physicians only. There are two types of masks generally available. One is a medical face mask, and the other is cloth face coverings. The medical face mask is a single-use mask. Its advantage is that it prevents asymptomatic carriers of the virus from affecting other individuals.
Cloth face coverings can be made in our homes too. However, it has to be made sure that the covering filters at least 70 percent of the particles. The general guideline is that any covering insofar that it covers your mouth and nose can be used. Plus, if we are using a valved mask, we prefer to use another cloth beneath the mask.
In a nutshell, it can be said that face masks are our most lethal weapon against the coronavirus after the vaccines themselves. All the research has thus far favored the wearing of masks. A study of 198 countries globally found that in countries with “cultural norms or government policies supporting public mask-wearing, per-capita coronavirus mortality increased on average by just 8.0% each week, as compared with 54% each week in remaining countries.”