| Noon 24-March | Cases | Deaths | Parishes |
| St. Mary Parish | 2 | 0 | |
| Louisiana | 1,388 | 46 | 43 of 64 |
| United States | 45,786 | 544 | |
| World | 407,485 | 18,227 | |
| Italy | 69,176 | 6,820 |
MASKS
As the Covid-19 outbreak grows exponentially across the globe and particularly in the United States, there has been a run on medical masks of all types. This has created an acute shortage of masks for those in most in need of them, the doctors, nurses and emergency response personnel on the front line of the fight against this growing killer. All the while, masks which would be a big help in hospital settings are being used by average citizens who falsely believe they provide them with an adequate level of protection.
To discuss masks, we must first look at the three major types of masks available: respirators, manufactured surgical masks, and mostly homemade cloth masks. All of these have their place and uses, as we will see. However, those uses may not be applicable to the Covid-19 outbreak and SARS CoV 2 virus which causes it.
RESPIRATORS
Respirators are tightly fitting masks specifically designed to filter out the overwhelming majority of airborne particles. The most common respirator one will come across today is the N95 respirator. They are tight-fitting masks that filter out at least 95% of small and large airborne particles, according to the CDC. They are recommended for use by health care workers in the treatment of the coronavirus. However, even when properly fitted, an N95 mask “does not completely eliminate the risk of illness or death,” according to the Us Food and Drug Administration.
The N95 respirator is designed to filter out 95% of particles which are 300 nanometers (nm) in size or larger. This makes them effective against most airborne pathogens but not all. In fact, they are slightly less efficient against SARS CoV 2 as the average size of viral particles is only 100 nm. Thus a single SARS CoV 2 virus could race right through an N95 respirator.
Thankfully, the infected human body puts out thousands of these particles, many of them attach to mucous or water molecules in coughs and sneezes. The latter virus particles, attached to say mucous or even a water molecules, are much then too big to pass through N95 pores.
While free floating virus particles may be smaller than the pores of the mask, thankfully there are so many of them that they clog pores when more than two try to enter. Think of this analogy: one teenage boy can easily fit through a standard doorway, but if three of them try to get through at the same time, it just does not work. So, in this case, we use the massive reproduction of the SARS CoV 2 against itself.
All that said, it is not a complete solution. By their very nature, N95 respirators only block 95% of those particles 300 nm and larger. On average 5% get through. The small size of SARS CoV 2 likely bumps that percentage up even more. This also assumes the respirator is properly fitted and applied. This is not always that easy.
“Achieving an adequate seal to the face is essential,” according to the CDC. “United States regulations require that workers undergo an annual fit test and conduct a user seal check each time the respirator is used. Workers must pass a fit test to confirm a proper seal before using a respirator in the workplace. When properly fitted and worn, minimal leakage occurs around edges of the respirator when the user inhales.” This makes N95 respirators very uncomfortable to wear and dangerous for those with various health conditions, including those who are pregnant, due to the reduction in air flow. Nor can they be effectively used by those with facial hair.
N95 respirators are also supposed to be single use masks for health care workers, but with the acute shortage of this vital protective device worldwide, many health care workers are being asked to save their N95s and reuse them. This also decreases efficiency. In addition, it becomes more difficult to assure good face seals with repeated use. Finally, the continued use of N95 respirators by health care workers can cause skin breakdown along the seal area from the constant pressure of the mask.
SURGICAL MASKS
“A surgical mask is a loose-fitting, disposable device that creates a physical barrier between the mouth and nose of the wearer and potential contaminants in the immediate environment,” according to the CDC. “Surgical masks are regulated under 21 CFR 878.4040. Surgical masks are not to be shared and may be labeled as surgical, isolation, dental, or medical procedure masks. They may come with or without a face shield. These are often referred to as face masks, although not all face masks are regulated as surgical masks.”
These are the masks used by dentists, doctors and nurses in normal daily activities. They are also the same as most such masks sold at drug stores and such. Some face masks may not be designed to the statute noted above and thus are not labeled as “surgical masks.” However, for our purposes, we will treat all these the same as their protective qualities are quite similar.
Where an N95 respirator can stop particles down to 300 nm in size, surgical masks are designed to stop particles down to 5000 nm in size. We go from three virus particle-width pores to 50 particle-width pores. This size of opening is not even completely effective against larger, virus laden, mucous particles in coughs and sneezes. This is because surgical masks are not designed to stop such small particles.
“If worn properly, a surgical mask is meant to help block large-particle droplets, splashes, sprays, or splatter that may contain germs (viruses and bacteria), keeping it from reaching your mouth and nose,” according to the CDC. “Surgical masks may also help reduce exposure of your saliva and respiratory secretions to others.”
They are designed to protect the health care workers from fluids that may be splashed or projected towards them in procedures. They also help prevent coughs or sneezes from transmitting as many particles from the health care worker reaching the patient. They are not designed to protect the health care worker from whatever disease the patient has. That job goes to the N95 respirators.
Finally, surgical masks are not fit to the person’s face. By their very design, they allow air flow around the mask. Thus, virus laden air flow can just travel right around the sides and infect the wearer. This makes them very ineffective against Covid-19.
CLOTH MASKS
The last form of masks are cloth masks being sewn across the country by those trying to help health care workers face growing shortages. For the most part, anything written about surgical masks applies to cloth masks as well. They are not adequate replacements for N95 respirators, nor truly as effective as surgical masks. A study published in The Annals of Occupational Hygiene showed that up to 70% of infective particles were able to penetrate average cloth masks. It must also be remembered that efficacy is based upon the type of cloth used, the number of layers and other factors. In general, though, hand-sewn cloth masks should not be considered as effective as surgical masks and are nowhere near the effective nature of N95 respirators.
That said, the sewing of such masks for use by health care workers is highly encouraged. Any protection is better than no protection at all, which is what many health care workers will soon be facing. These efforts are admirable and health care workers across the country are applauding the assistance.
CONCLUSION
The only masks which offer any true protection against the SARS CoV 2 virus are N95 respirators. The CDC does not recommend the use of N95 respirators outside of hospitals and other medical workplace settings. This scarce resource is essential to protecting health care workers on the front lone of the Covid-19 outbreak. Using them anywhere else puts a health care worker in danger and potentially reduces the health care workforce which you may need if or when you get Covid-19.
“Most often, spread of respiratory viruses from person-to-person happens among close contacts (within 6 feet),” notes the CDC. Rather, all of us should use everyday preventive actions to prevent the spread of Covid-19, such as avoiding people who are sick, avoiding touching your eyes or nose, and covering your cough or sneeze with a tissue or your elbow. People who are sick should stay home and not go into crowded public places or visit people in hospitals.
Simply washing your hands as often as possible and social distancing are far more effective means of preventing the spread of, or acquiring, Covid-19 than any use of face masks, even N95 respirators.
