With COVID-19 infections in the United States increasing daily, the basic steps recommended by the Centers for Disease Control and Prevention (CDC) may be more important than ever. Following the simple guidelines — such as wearing a cloth mask in public places where you cannot maintain 6 feet of distance from others — could reduce the severity of the illness if you are infected.
While cloth face masks can’t completely prevent the spread of the virus, according to a study published in the Journal of Internal Medicine, masks can lead to milder cases or asymptomatic cases by reducing the dose of the virus the wearer takes in. Dr. Monica Gandhi, an infectious disease specialist at the University of California, San Francisco, is one of the authors of the study. She explained the COVID-19 virus is most commonly spread from person to person in the droplets of moisture that leave the mouth and nose when you cough, sneeze or talk. Cloth masks help catch much of that moisture, reducing the amount of the virus that may be spread to others.
The study also notes that in countries where mask wearing was already commonplace, such as Japan, Taiwan, Thailand, South Korea and Singapore, rates of severe illness and death from COVID-19 have remained comparatively low.
In an article titled “Cloth masks protect: Breathing in fewer viruses means you get less sick,” published on the website science.thewire, Gandhi explained: “Masks slow the spread of SARS-CoV-2 by reducing how much infected people spray the virus into the environment around them when they cough or talk. Evidence from laboratory experiments, hospitals and whole countries show that masks work, and the CDC recommends face coverings for the U.S. public.
“I am an infectious disease doctor and a professor of medicine at the University of California, San Francisco. As governments and workplaces began to recommend or mandate mask wearing, my colleagues and I noticed an interesting trend. In places where most people wore masks, those who did get infected seemed dramatically less likely to get severely ill compared to places with less mask-wearing,” she wrote.
“When you wear a mask — even a cloth mask — you typically are exposed to a lower dose of the coronavirus than if you didn’t. Both recent experiments in animal models using coronavirus and nearly a hundred years of viral research show that lower viral doses usually mean less severe disease. No mask is perfect, and wearing one might not prevent you from getting infected. But it might be the difference between a case of COVID-19 that sends you to the hospital and a case so mild you don’t even realize you’re infected.”
A similar study published on medRxiv (an online server for health sciences) reached the same conclusion. The authors explained the peak viral load shed by a person who is contagious may occur before the person has any symptoms. An infected person may be most contagious before they have a fever or other symptoms. Masks help protect others from being infected by those who are asymptomatic.
“If we could get everybody to wear a mask right now, I really think in the next four, six, eight weeks, we could bring this epidemic under control,” Robert Redfield, director of the Centers for Disease Control and Prevention, explained in a Journal of the American Medical Association webcast in July.
Redfield cited the case of two hair stylists in Springfield, Mo., who kept working even though they had respiratory symptoms, and then tested positive for COVID-19. The two had contact with 139 clients during the time they were believed to be contagious before testing positive. The contacts ranged from 15 to 45 minutes each. The health department followed up with all of those believed to have been exposed and found no cases of COVID-19. None had symptoms, and none of the 67 who agreed to a swab test were positive. How did they avoid infecting others? Both stylists and all of the salon’s client had worn face coverings.
On Oct. 5, the CDC issued updated guidance to its “How COVID-19 Spreads” website, which includes information about the potential for airborne spread of the virus that causes COVID-19.
CDC continues to believe, based on current science, that people are more likely to become infected the longer and closer they are to a person with COVID-19. The update acknowledges the existence of some published reports showing limited, uncommon circumstances where people with COVID-19 infected others who were more than 6 feet away or shortly after the COVID-19-positive person left an area. In these instances, transmission occurred in poorly ventilated and enclosed spaces that often involved activities that caused heavier breathing, like singing or exercise. Such environments and activities may contribute to the buildup of virus-carrying particles.
CDC’s recommendations remain the same based on existing science and after a thorough technical review of the guidance.
People can protect themselves from the virus that causes COVID-19 by staying at least 6 feet away from others, wearing a mask that covers their nose and mouth, washing hands frequently (most especially before touching your face), disinfecting frequently touched surfaces and staying home when sick.