Your Mask Cuts Own Risk by 65 Percent
By: Rick Kushman (UC Davis)
We also know that close contact with someone who is not infected will not transmit the virus. In that situation, the mask protects against nothing.
The need for masks address two possibilities. The first possibility is that people are ignoring the symptoms of COVID and going out in public anyway. During a pandemic, ignoring COVID symptoms and going out in public is highly irresponsible behavior. The mandates should address this highly irresponsible behavior to prevent spread of the virus.
The second possibility is that the virus is so benign that a large number of people do not experience COVID symptoms and simply do not know they are infected. The guidelines can address this possibility by recommending hygiene practices of gargling and nasal irrigation. These common hygiene practices can significantly reduce the amount of virus that an infected individual can spread.
As the reported research shows, masks and social distancing are not completely effective. And it is simply impossible to follow the mandates and guidelines for masks and social distancing perfectly all the time. While the research does show that masks and social distancing can reduce spread of the virus, that evidence really doesn't indicate that the pandemic can be controlled with masks and social distancing alone.
The mandates and guidelines aren't doing enough. We need to directly address the infection, itself, by addressing irresponsible behavior and through better hygiene. That won't eliminate the need for masks and social distancing but would greatly improve the effectiveness of measures to control the pandemic.
S E E D E D C O N T E N T
A range of new research on face coverings shows that the risk of infection to the wearer is decreased by 65 percent, said Dean Blumberg, chief of pediatric infectious diseases at UC Davis Children's Hospital.
"On the issue of masks, I'd like to restart — because we've learned a lot," Blumberg said. "We've learned more due to research and additional scientific evidence. What we know now is that masks work and are very important."
Blumberg and William Ristenpart, a professor of chemical engineering at UC Davis, appeared on the July 2 livestream devoted to explaining how the virus spreads and how to prevent transmission.
In their comments and answers to questions from viewers, Blumberg and Ristenpart repeatedly made the point that research continues to support the fundamental methods to prevent spreading COVID-19: Wear masks, maintain social distance and keep social interactions outdoors whenever possible.
Transmission by droplets
There are two primary methods of transmission, they said. The first is via droplets a carrier expels, which are about one-third the size of a human hair but still large enough that we can see them. Masks create an effective barrier against droplets.
"Everyone should wear a mask," Blumberg said. "People who say, 'I don't believe masks work,' are ignoring scientific evidence. It's not a belief system. It's like saying, 'I don't believe in gravity.'
"People who don't wear a mask increase the risk of transmission to everyone, not just the people they come into contact with. It's all the people those people will have contact with. You're being an irresponsible member of the community if you're not wearing a mask. It's like double-dipping in the guacamole. You're not being nice to others."
Transmission by aerosol particles
The second major transmission method is via the aerosol particles we expel when we talk. Those are about 1/100th the size of a human hair and are more difficult to defend against. Social distancing and staying outdoors, where there is more air flow, are helpful, Blumberg and Ristenpart said.
"Studies in laboratory conditions now show the virus stays alive in aerosol form with a half-life on the scale of hours. It persists in the air," Ristenpart said. "That's why you want to be outdoors for any social situations if possible. The good air flow will disperse the virus. If you are indoors, think about opening the windows. You want as much fresh air as possible."
This is why, he said, places like bars are particularly hazardous for aerosols, on top of the likelihood of minimal distancing. "The louder you speak, the more expiatory aerosols you put out," he said.
Other topics
Plexiglass and cubicles as protection? — The plexiglass shields in stores and restaurants only help somewhat. The same is true for office cubicles. But after a lengthy time, transmission is possible from aerosols if the air flow is not good, they said.
"The way to think about that is to think about smells," Ristenpart said. "If the person on the other side of a cubicle or plexiglass is wearing perfume, eventually, you'll smell it. The aerosol particles are small enough to travel on air much like aromas. That's why air flow is so important, along with other actions like wearing masks and social distancing."
Time of exposure matters — "If you're going past someone very quickly in a grocery store," Blumberg said, "the risk of getting infected is very low. It's really lingering and talking that does it."
Ristenpart added: "It's really important to know that just because you're standing 6 feet or 7 feet away, if you have a prolonged conversation, there is still a risk. These aerosols can be carried along on weak air currents."
Surface contact is less of a threat — There is no precise research on the prevalence of transmission from hand contact. "For ethical reasons, we can't contaminate a bunch of people's hands, then have them touch their faces or other people's faces," Ristenpart said. "But backtracking infections and following transmission events shows surfaces or hand contacts are not a primary method."
Which brings researchers back to droplets and aerosol particles as the primary methods of transmission.
"We know from other coronaviruses that this is primarily a respiratory transmitted illness," Blumberg said. "There is a very small chance of transmission via groceries or mail or things like that. But washing hands is still always good."
Children and COVID-19 — Children are less likely — by half — to be infected if they are exposed, less likely to be symptomatic and less likely to have a severe case if they do get sick, Blumberg said.
"They appear to be less likely to infect others," he said. "This is different from other infections like the flu when they are carriers. This appears to be much more of an adult disease. But children can still get sick and can still transmit it to others, so it's important to be as hygienical with them as their development allows."
Connecting the research
Both scientists said the evidence has become even more powerful for wearing masks and social distancing. For instance, research shows that about 30 percent of infections are caused by people who do not know they have COVID-19 because they are asymptomatic or their symptoms have not appeared yet.
"So we don't know who might spread it," Blumberg said. "We do know social distancing reduces the risk of transmitting the virus by 90 percent, and wearing masks decreases the risk by 65 percent.
"Wearing a mask affects everyone," he said. "If you care about your family or friends, or if you care about your community, wear a mask."
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Attacking people won't control the pandemic. We need to attack the virus where it lives. The current mandates and guidelines are not doing enough.
If nasal swabbing to collect a test sample included disinfection of the nasal passage where the virus lives then we would be closer to controlling the pandemic. A simple gargle and spit at the testing station might be more effective than what we have been doing.
Nerm...I have to ask...how do you plan to disinfect the nasal passage while collecting a sample? The disinfectant will render the sample unusable. Unless you intend to put a swab up somebody's nostril twice.
Well obviously the sample must be collected first. Nasal disinfection isn't something new. Nasal disinfection is being used to control spread of infections in hospitals. Isn't the idea to control spread of infection during the pandemic?
Prevent infections during hospital stay (opens a small PDF)
3M produces nasal antiseptics
Your little pdf says bacteria. Doesn't say one word about viruses. Viruses are a hell of a lot trickier to kill than bacteria.
And your 3M product:
Once again talking about bacteria. What do you think "septic" refers to?
Alright. Here are a couple of articles directed specifically toward SARS-CoV-2. The use of nasal antiseptics are being studied as a means to control infection and as a prophylactic treatment to prevent COVID-19.
Treatments that target the coronavirus in the nose might help prevent COVID-19
In Vitro Efficacy of Povidone-Iodine Nasal And Oral Antiseptic Preparations Against Severe Acute Respiratory Syndrome-Coronavirus 2 (SARS-CoV-2)
The scientific community was caught with its pants down by the pandemic. But scientific research is being conducted on the effectiveness of nasal and oral disinfection to reduce spread of the virus and as possible prophylactic treatments to prevent COVID. Search the literature for yourself.
Google Scholar can be your friend.
Being studied is the key phrase and I see another phrase that says "might help". IOW there is no definitive proof that it works
Emphatically.
And that is the problem with fake community 'experts' and hard-headed combative presidents and a VP in-charge of the committee who won't internalize his own safety guidelines. "Being studied," is a qualifier. It is something one can consider. An "anecdote" in quotes. It is not an assertion.
If people were to actually adhere to the guidelines of masks & distancing, the virus would probably be much better controlled. Those who do not follow guidelines only contribute to and compound the problem.
Woman in her 30s died from COVID-19 on a flight - CBS News
Obviously the woman was wearing a mask since that is what the mandates require.
How does someone experiencing COVID symptoms blow their nose with a mask on? Someone can blow their nose, put on a mask, and walk into a store where they spread virus on everything they touch. Why don't the mandates address this type of irresponsible behavior?
People need to be responsible and cognizant of their situation themselves. If one is experiencing symptoms, clearly it's a bad idea to go out & travel. Some places like hospitals screen all visitors for covid. The airlines should do the same.
What are you arguing for or against?
Moreover, when I am in stores I see it all the time. People cough. They 'palm.' Children 'grope' whole stacks of products. I stay calm. Pick what I can off the back-side of the shelves, take it home accordingly and 'hose' it down using approved procedures. Responsible.
Oh, and gloves. We can all use gloves more this winter. (I do everywhere.) Wash, Rinse. Repeat.
I am arguing that the mandates need to be expanded to include punitive measures against those who go out in pubic while experiencing symptoms of COVID. I am also arguing that the guidelines should be expanded to include hygienic recommendations such as gargling and nasal irrigation.
If we can fine people $250,000 for not wearing a mask then we should be able to fine people $1 million for going out in public while experiencing symptoms of COVID.
Those updates for both mandates and guidelines should be added onto existing mandates and guidelines.
Masks combined with hand washing and social distancing are 95% effective at limiting the spread of Covid-19. Nothing is 100% against this virus...
And the need for masks, hand washing, and social distancing is because people are ignoring COVID symptoms and going out in public - or - the infection is so benign that people do not know they are infected.
The mandates and guidelines can include measures to address both those possibilities. Are the mandates and guidelines doing enough?
Politicizing masks to attack people won't control the pandemic. And we can be doing much more than just wearing masks, washing hands, and social distancing.
There are no good excuses for not following all of the recommended protocols...
Yes, everyone should be following the guidelines by wearing masks, washing hands, and social distancing.
What I am pointing out is that more needs to be done. Mandates should address people ignoring COVID symptoms and going out in public anyway. Guidelines should include hygienic practices that attack the virus where lives in the nasal and oral cavities.
Surely we've learned enough by now to improve upon mandates and guidelines.
Oh, so you are advocating for a unified message from the 'top'?
Oh! So now we're all for masks and social distancing!
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[deleted] one of those people who wishes to ignore the fact-based writings, forget the doctors and professionals who manage the sick, dying, and pull the sheets up over the dead - ignore the scientists with their high-intensity microscopes and tubes.