As states resume many of their non-essential activities and businesses the Centers for Disease Control and Prevention (CDC) issued recommendations to all Americans. Those CDC guidelines are based on updated infection numbers and current knowledge of viral transmission. During the shelter in place essential businesses and their employees were advised to wear masks, gloves and avoid touching the face. As more businesses open the CDC is now recommending that EVERYONE who ventures out in public wear some sort of facial covering. Since viral testing has become more widespread we are discovering that a substantial number of individuals infected with the virus have no symptoms. These “super spreaders” could be shedding the virus unintentionally. A cloth or surgical-type mask will help prevent any respiratory or nasal droplets from becoming airborne and potentially infecting others. A facial covering need not be the “Cadillac” N95 mask that is recommended for frontline healthcare workers. In fact you could be wearing one type of N95 that does more harm than good. There are several types of the N95 mask, one is designed for industrial use and another for medical use. The industrial mask has a one-way valve that serves solely to protect the wearer. The one-way valve blocks incoming particulates but permits exhalation of respiratory droplets that could be infectious with the virus. The N95 mask for medical use lacks the one-way valve and protects patient and medical personnel. The CDC recommends that N95 masks for medical use be reserved ONLY for first responders and hospital personnel in direct contact with infected patients. The N95 mask must be “fitted” to the individual’s face assuring a good seal thereby preventing air from entering around the mask edges. The effectiveness of the N95 is accomplished through an inner nonwoven polypropylene fabric mesh that blocks fine particles and viruses. A simple surgical mask or cloth covering is sufficient for most people provided the surgical mask is changed daily. If choosing to wear a cloth mask it should be washed regularly. Facial coverings are still no substitute for frequent handwashing and physical distancing as a method of preventing spread of the virus.
It is important to remember that a surgical or cloth mask will NOT protect an individual if you are exposed to a COVID-19 patient. They are ineffective in filtering viruses and do not maintain an effective seal around the mouth and nose. Even the N95 masks must be cleaned or “decontaminated” after a given period of use. Duke University discovered a method of sterilizing masks by exposing them in a room to hydrogen peroxide vapor. The CDC found ultraviolet irradiation and moist heat were additional promising methods for decontaminating N95 masks. Masks that become contaminated with body fluids should not be decontaminated and reused regardless of the method. As with other critical personal protective equipment (PPE), production of N95 masks had previously shifted to foreign nations. At the onset of the COVID-19 pandemic China controlled 50% of global mask production. President Trump invoked the Defense Production Act and encouraged 3M to step up their production of N95 masks. The U.S. was also able to divert a shipment of 200,000 masks from Bangkok to the U.S. We will not be totally safe in public until there is herd immunity. That can only be achieved when enough individuals have been vaccinated or infected with the virus and recovered. It is NOT necessary to wear a mask in your home or car (provided you are only with those you have been in quarantine with). It is also not necessary (in general) when outdoors unless you are unable to practice social distancing. Whether you FEEL sick or not, you could still be shedding the virus and a mask is the best way to prevent spread to others. You are also setting an example of appropriate behavior to those who may believe that a mask isn’t needed. As responsible Americans we can count on each other to do the right thing!