For the first time, the Center for Disease Control and Prevention (CDC) has recommended that even seemingly healthy people wear masks over their mouths and noses when venturing out of their homes into places where it is difficult to maintain distance from other people. But there is still major debate over exactly how much masks – particularly the Face Masks For Coronavirus that the CDC recommends for the public – can slow the spread of SARS-CoV-2, the virus that triggers COVID-19.
Researchers, writing in 2 new papers, attempt to tackle the efficacy of masks, one more rigorously compared to other, and are available to differing conclusions. One study examined the result of masks on seasonal coronaviruses (which cause many cases in the common cold) and found that surgical masks are helpful at reducing how much virus a sick person spreads. One other looked particularly at SARS-CoV-2 and found no effect of either surgical or fabric masks on reducing virus spread, only had four participants and used a crude measure of viral spread.
The base line, experts say, is the fact that masks might help keep people who have COVID-19 from unknowingly passing across the virus. Nevertheless the evidence for that efficacy of surgical or homemade masks has limitations, and masks aren’t the most crucial protection against the coronavirus.
“Placing a face mask on fails to mean which you stop one other practices,” said May Chu, a clinical professor in epidemiology at the Colorado School of Public Health on the Anschutz Medical Campus who had been not involved in either new study. “It does not mean you receive nearer to people, it does not mean you don’t must wash your hands as much and you also can touch your face. All of that still is within place, this is just an add-on.”
Face mask basics
Recommendations about Masks For COVID-19 can easily get confusing, because all masks are certainly not made equal. The N95 mask effectively prevents viral spread. These masks, when properly fitted, seal closely towards the face and remove 95% of particles .3 microns or larger. But N95 masks are in serious shortage even for healthcare professionals, who definitely are in contact with the greatest degrees of SARS-CoV-2 and therefore are most needing the strongest protection from the virus. They’re also difficult to fit correctly. For all those reasons, the CDC does not recommend them for general use.
Due to shortages, the CDC also fails to recommend surgical masks for your general public. These masks don’t seal against the face but do include non-woven polypropylene layers which can be moisture resistant. In a surgical mask, about 70% of the outside air moves from the mask and about 30% travels across the sides, Chu told Live Science. For that reason, they don’t offer the maximum amount of protection as N95s.
That leaves fabric masks, which currently are appropriate for general use by the CDC. Fabric masks also allow air in across the sides, but lack non-woven, moisture-repelling layers. They impede no more than 2% of airflow in, Chu said.
All this leakage in surgical and fabric masks are why public health officials generally don’t feel that wearing a mask prevents anyone from catching a computer virus that is already floating around in the environment. Airflow follows the path of least resistance, said Rachael Jones, an associate professor of family and preventive medicine at the University of Utah who has been bevggk working in the new information. If viral particles are nearby, they may have a simple path around a surgical or fabric mask. As well as in the case of the fabric mask, wearers may well be wafting in particles small enough to flow right from the fabric.
But have you thought about the other way around? If the wearer of Masks For COVID-19 coughs or sneezes, the barrier might be sufficient to contain a lot of that initial jet of grossness – even if you can find gaps inside the fabric or around the sides. That’s just what the new mask studies aimed to address: Whether surgical or fabric masks did a great job of containing viruses.