Science
Related: About this forumReducing transmission of SARS-CoV-2
This somewhat scary "perspective" is found in the current issue of Science: Reducing transmission of SARS-CoV-2 (Kimberly A. Prather1, Chia C. Wang2,3, Robert T. Schooley4 Science 26 Jun 2020: Vol. 368, Issue 6498, pp. 1422-1424)
I presume it's open sourced:
Some excerpts:
Humans produce respiratory droplets ranging from 0.1 to 1000 µm. A competition between droplet size, inertia, gravity, and evaporation determines how far emitted droplets and aerosols will travel in air (4, 5)...
...it is possible that submicron virus-containing aerosols are being transferred deep into the alveolar region of the lungs, where immune responses seem to be temporarily bypassed. SARS-CoV-2 has been shown to replicate three times faster than SARS-CoV-1 and thus can rapidly spread to the pharynx, from which it can be shed before the innate immune response becomes activated and produces symptoms (6). By the time symptoms occur, the patient has transmitted the virus without knowing...
...The U.S. Centers for Disease Control and Prevention (CDC) recommendations for social distancing of 6 feet and hand washing to reduce the spread of SARS-CoV-2 are based on studies of respiratory droplets carried out in the 1930s. These studies showed that large, ?100 µm droplets produced in coughs and sneezes quickly underwent gravitational settling (1). However, when these studies were conducted, the technology did not exist for detecting submicron aerosols...
...Measurements now show that intense coughs and sneezes that propel larger droplets more than 20 feet can also create thousands of aerosols that can travel even further (1). Increasing evidence for SARS-CoV-2 suggests the 6 feet CDC recommendation is likely not enough under many indoor conditions, where aerosols can remain airborne for hours, accumulate over time, and follow airflows over distances further than 6 feet (5, 10)...
The article goes on to suggest an explanation of why Taiwan, despite having no lockdown, had a low infection rate, while the United States didn't.
Hint: Not that we wish to offend members of the Trump cult here at DU, it involves, um, masks. The article suggests that "social distancing" may not be enough.
A graphic:
The caption:
Infectious aerosol particles can be released during breathing and speaking by asymptomatic infected individuals. No masking maximizes exposure, whereas universal masking results in the least exposure.
It is important to note, and it's easy to forget this, that wearing a mask does not protect the wearer so much as it protects other people. This explains the Republican resistance to wearing them. They just don't give a shit about other people.
AllaN01Bear
(17,944 posts)how hard is that to do.
BigmanPigman
(51,562 posts)It has been months...how fucking long does it take to make good masks? Didn't the fucking moron sign a paper for war-time production of masks or is that sitting in the THINGS I DO NOT CARE ABOUT folder on his desk under the info about Putin's $$$ to Taliban?
NNadir
(33,457 posts)...I can tell you that scale up is not quite like turning on the spigot.
Supply chains can be quite inflexible and problematic.
I had two N95's in my house, because my son was working with a sculptor. Going from the set of sculptors and construction workers to the entire planet is a big chore.
Arsenalpe
(3 posts)Hoo Noo! How dangerous we are in now? I don't know what to do now. I have one doubt. Masks can control the virus? Because the virus can live in clothes or paper etc. We carry that infected mask into our home only. We pick that mask in our hands only. Is it safe? I am happy about that thing i.e., to wear a mask to control the virus. Please give some advice about how to take care of masks or which type of masks are using better
NNadir
(33,457 posts)The lifetime of masks depends on the material with which they are made, as does treatment.
Some masks are cloth materials that can be washed. We know that surfactants, soaps, inactivate the virus. We also know that the lifetime of the virus on surfaces is not infinite.
I circulate my masks, keeping them in a hot car to minimize the stability of the virus. I have two N95's that my son had left over from his days as a sculpture intern. I've been switching them out each week.
Personally, when handling my masks after a long day, I gel my hands.
The bottom line however is that wearing a mask is an exercise in protecting - for the most part - other people. It offers some protection to one's self, but it is not 100% effective; it just improves your odds. If your mask is highly infected, it is probable that you are infected as well.
Recognizing this, I try to stay as far away from people who are not wearing a mask. They are more dangerous to you than your own mask.
I hope this helps.
Boomer
(4,167 posts)You can't catch the coronavirus through the skin of your hands, so if you touch your mask AND THEN WASH YOUR HANDS, you should be fine. As long as you don't touch your face in between. So my routine when returning home is to wash my hands, take off my mask and store it away, and then wash my hands again.
And just a pedantic side note: what I've read is that soap has no effect on the virus itself, it just helps wash the virus away from your skin.
NNadir
(33,457 posts)The virus has a lipid layer that is essential to its ability to be infectious. Soap disrupts this layer.
This lipid envelop is critical to infection, since it allows fusion with the cell membrane:
COVID-19 is a single, positive-stranded RNA virus enveloped in a lipid bilayer [6,7]. The lipid bilayer fuses with the host cell membrane, releasing RNA into the cytoplasm and causing translation of various viral proteins. The replicated RNA genome and synthesized viral proteins reassemble into new viruses, which burst out of the cell [8,9].
Epidemiology and clinical features of COVID-19: A review of current literature (Siordia, Journal of Clinical Virology Volume 127, June 2020, 104357)