As for the scientific support for the use of face mask[s], a recent careful examination of the literature, in which 17 of the best studies were analyzed, concluded that, “None of the studies established a conclusive relationship between mask/respirator use and protection against influenza infection.” Keep in mind, no studies have been done to demonstrate that either a cloth mask or the N95 mask has any effect on transmission of the COVID-19 virus. Any recommendations, therefore, have to be based on studies of influenza virus transmission. And, as you have seen, there is no conclusive evidence of their efficiency in controlling [flu-virus] transmission.
It is also instructive to know that until recently, the CDC did not recommend wearing a face mask or covering of any [kind unless] a person was known to be infected. Non-infected people need not wear a mask. When a person has TB[,] we have [him] wear a mask, not the entire community of non-infected. The recommendations by the CDC and the WHO are not based on any studies of this virus and have never been used to contain any other virus pandemic or epidemic in history.
Now that we have established that there is no scientific evidence necessitating the wearing of a face mask for prevention, are there dangers to wearing a face mask, especially for long periods? Several studies have indeed found significant problems with wearing such a mask. This can vary from headaches, to increased airway resistance, carbon dioxide accumulation, to hypoxia, all the way to serious life-threatening complications.
[...]
Unfortunately, no one is telling the frail elderly and those with lung diseases, such as COPD, emphysema[,] or pulmonary fibrosis, of these dangers when wearing a facial mask of any kind—which can cause a severe worsening of lung function. This also includes lung cancer patients and people having had lung surgery, especially with partial resection or even the removal of a whole lung.
While most agree that the N95 mask can cause significant hypoxia and hypercapnia, another study of surgical masks found significant reductions in blood oxygen as well. In this study, researchers examined the [blood-oxygen] levels in 53 surgeons using an oximeter. They measured blood oxygenation before surgery as well as at the end of surgeries. The researchers found that the mask reduced the [blood-oxygen] levels (Pa02) significantly. The longer the duration of wearing the mask, the greater the fall in [blood-oxygen] levels.
[...]
There is another danger to wearing these masks on a daily basis, especially if worn for several hours. When a person is infected with a respiratory virus, [he] will expel some of the virus with each breath. If [he is] wearing a mask, especially an N95 mask or other tightly fitting mask, [he] will be constantly rebreathing the viruses, raising the concentration of the virus in the lungs and the nasal passages. We know that people who have the worst reactions to the coronavirus have the highest concentrations of the virus early on. And this leads to the deadly cytokine storm in a selected number.
It gets even more frightening. Newer evidence suggests that[,] in some cases[,] the virus can enter the brain. In most instances[,] it enters the brain by way of the olfactory nerves (smell nerves), which connect directly with the area of the brain dealing with recent memory and memory consolidation. By wearing a mask, the exhaled viruses will not be able to escape and will concentrate in the nasal passages, enter the olfactory nerves[,] and travel into the brain.
It is evident from this review that there is insufficient evidence that wearing a mask of any kind can have a significant impact in preventing the spread of this virus. The fact that (1) this virus is a relatively benign infection for the vast majority of the population[,] and that (2) most of the at-risk group also survive, from an infectious disease and epidemiological standpoint, by letting the virus spread through the healthier population[,] we will reach a [herd-immunity] level rather quickly that will end this pandemic quickly and prevent a return next winter. During this time, we need to protect the at-risk population by avoiding close contact, boosting their immunity with compounds that boost cellular immunity and in general, care for them.
One should not attack and insult those who have chosen not to wear a mask, as these studies suggest that is the wise choice to make.
Some reactions from the Instapundit comment section:
(1)
Masks are not perfect, and should be changed regularly. Don't wear the same mask more than one day. Wash it and either dry it in sunlight or in a hot dryer. With influenza which has a very short asymptomatic period masks for health people don't make sense. Most of the pandemic plans were based on variations of influenza. COVID-19 has a long asymptomatic period, and that is why they have helped countries the implemented them early to keep infections down despite being densely populated - Singapore, Thailand, South Korea for examples. The recent uptick in Singapore is among migrant workers who live in dormitories. They spread it where they sleep.
(2)
“Keep in mind, no studies have been done to demonstrate that either a cloth mask or the N95 mask has any effect on transmission of the COVID-19 virus.“
Taiwan, South Korea, Hong Kong, and Japan seem to have demonstrated they work. Overwhelmingly.
Let’s save the economy! Unless we have to wear masks?
(3)
Absolute garbage. Best is if we stop the stupid lockdowns . Let the high risk stay home. The rest of us all wear masks wash our hands a lot and return to work. Ask Taiwan and Singapore.
(4)
All I know is Asian countries where masking is common have much lower rates of infections, hospitalizations, deaths, etc. Who am I going to believe: my own eyes, or an "expert" favored by some third-rate sci-fi author who "wakes up screaming" every morning?
I've been a mask skeptic from the beginning. John McCrarey recently posted a humorous pic of a guy setting up a chain-link fence "to stop mosquitoes" as an analogy for the effectiveness of most masks against viruses. You could argue that N95 masks are less porous than the fence analogy would have you believe, but as long as the seal against your face isn't perfect, the fact of the matter is that you're letting in plenty of air through the sides of the mask with every intake of breath. You're also doing nothing to protect your eyes, and SARS-CoV-2 can get in through the eyes. The best and most convincing argument for wearing the masks has been the commonsense notion that masks aid with the droplet problem that arises from coughing and sneezing. Most masks do not, however, stop aerosolized microparticles. So get used to the fact that, mask or not, you're taking a gamble every time you step out the door. Life is risk.
Overall, people are concluding that SARS-CoV-2 isn't nearly as deadly as once believed, but it is highly contagious, which is why, even months after the outbreak began, people are still saying that we are all "likely" to contract COVID-19 at some point.* For most of us, this won't mean much: either we won't even notice that we're infected, or our symptoms will be minimally debilitating. The obese, the diabetic, the people over 60, the people with preexisting respiratory conditions like COPD, etc.—they're the ones who have to take especial care. Your best bet to get through this crisis is to be an introvert who works at a quiet job—preferably somewhere far outside the city and away from crowded conditions.
*SARS-CoV-2 is the virus; COVID-19 is the disease caused by the virus. It's like the distinction between HIV (virus) and AIDS (disease).
And of course, whatever value masks may provide is contingent on whether they are worn properly. My observations when I'm out and about is that it is done maybe 60% of the time. Here any type of face-covering constitutes a mask. I don't see much effectiveness from a hanky tied across the mouth. I'm guilty as well, wearing mine under my chin unless I spot the authorities.
ReplyDeleteHaHa! I just posted the link on Facebook and got "fact-checked". I guess they decided one part of the post about the adverse impact on a healthy immune system to be untrue. We'll see how long it stays up on my page.
ReplyDeleteI saw the joke that, when enough people stamp "TRUMP 2020" on their masks, the government will suddenly tell us that masks are no longer needed.
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