Re: Best Ways To Prevent & Treat Covid-19
Circumstantial evidence, nevertheless…
One more reason to wear a mask: You’ll get less sick from COVID-19
AUGUST 6, 2020
While it’s true that most face masks are more effective in preventing you from launching droplets into the air than breathing in already dispersed droplets—that doesn’t mean masks offer no protection to the wearer.
It’s likely that face masks, by blocking even some of the virus-carrying droplets you inhale, can reduce your risk of falling seriously ill from COVID-19, according to Monica Gandhi, M.D., an infectious disease specialist at UC San Francisco.
“The more virus you get into your body, the more sick you are likely to get,” she said.
In the latest wave of infections in the U.S., the wider use of masks may be one factor for the lower death rates, along with more testing, younger patients and better treatments, said Gandhi. A greater proportion of these new cases have been mild or asymptomatic, though more data is needed to see if they track geographically with higher rates of mask-wearing.
Worldwide, epidemiological patterns seem to provide a clue. In countries where mask wearing was already commonplace, such as Japan, Taiwan, Thailand, South Korea, and Singapore, and in countries where mask wearing was quickly embraced, such as the Czech Republic, rates of severe illness and death have remained comparatively low.
These epidemiological observations are among the evidence that Gandhi and colleagues cite in a paper in the Journal of General Internal Medicine, in which they propose that masks can lead to milder or asymptomatic infections by cutting down on the dose of virus people take in.
“Masks can prevent many infections altogether, as was seen in health care workers when we moved to universal masking. We’re also saying that masks, which filter out a majority of viral particles, can lead to a less severe infection if you do get one,” said Gandhi. “If you get infected, but have no symptoms—that’s the best way you can ever get a virus.”
The idea that viral dose, also known as viral inoculum, determines the degree of illness is not new, said Gandhi. Descriptions of a dose-mortality curve—how much of a virus is needed to cause death in an animal—were first published in 1938. And after all, the earliest vaccines, which were documented in 16th century China, involved exposing someone to a small amount of smallpox virus to induce mild illness and subsequent immunity.
A small number viral particles is more likely to be quelled by the immune system before they can proliferate, said Gandhi.
Researchers have studied dose dependency experimentally with other viral infections, like the flu. In a study with healthy volunteers, those who received a higher dose of the influenza A virus developed more severe symptoms.
In February, one of the first outbreaks of COVID-19 outside of China occurred on the Diamond Princess cruise ship docked in Yokohama, Japan. Of the 634 people on board who tested positive, about 18% of infections were asymptomatic. In March, an Argentinian cruise ship found itself in a similar predicament, but of the 128 people on board who eventually tested positive, 81% were asymptomatic.
A key difference, Gandhi noted, was that on the Argentinian ship, surgical masks were issued to all passengers and N95 masks to all staff as soon as the first passenger became sick.
More recently, an Oregon seafood processing plant where workers were required to wear face masks reported an outbreak of 124 cases, 95% of which were asymptomatic. Similarly, in a Tyson chicken processing plant outbreak in Arkansas where workers were provided mandatory masks, 455 out of 481, or nearly 95% were asymptomatic.
Chris, if you get the chance please have a look at this paper If you have not already done so:
It may complement your explanation of what appears to be populations reaching herd immunity.
I don’t claim to have followed the mathematical details, but the gist seems to be that the population is unlikely to be uniformly susceptible to infection. This means that if infection/immunity is acquired by natural means as opposed to by vaccination, the most likely people to be infected early on are those with high susceptibility. This then only leaves those that are less susceptible to infection, thus lowering the effective R more than might be expected if everyone were uniformly susceptible.
There seemed to be a similar argument for those that have more connections/interactions with others. Some people are much more connected than others, (e.g. travel more, meet more people, are in closer contact with others such as on public transport, etc). These people are both more likely to get infected and more likely to pass the infection on, so are again likely to be taken out early (infected and rendered immune or die). This means that those that remain for a potential second wave are likely to be less connected, again reducing the effective R.
In the paper I believe that they combined both of these effects into a single parameter CV in their graphs, and the good news (assuming that their modelling is correct) is that as CV increases (I.e. bigger unevenness in susceptibility and/or connectedness), the threshold for herd immunity rapidly diminishes, and could be as low as 10% or 20%.
Hopefully, the shape of the infection curve in places that have been hardest hit is evidence that CV is sufficiently large as to prevent a second wave.
Of course, even if this is the case we still don’t know how long immunity lasts, so personally I’m glad to be in Western Australia where, at least for now, we seem to have eliminated the virus and have pretty much sealed the borders.
Selenium could be one of the key environmental factors for areas with high clusters.
The reason: Ebola and other deadly viruses, including the human immunodeficiency virus 1 (HIV-1), might be stimulated by deficiencies in the mineral selenium.
And Zaire-where the Ebola and HIV-1 viruses first appeared-may be a viral “hot zone” because of low selenium levels in the soil and widespread selenium deficiencies among people living off that land.
Too strange to be true? To the contrary, a similar connection has been established in China, where a common virus mutates into a dangerous form when it infects people deficient in selenium.
Selenium, an essential mineral, functions as an antioxidant and a component of another antioxidant, glutathione peroxidase. Deficiencies of either substance impair the body’s immune system and ability to fight infections. But if recent research is any indication, the role of selenium in disease prevention may be much more profound than previously imagined.
Admittedly, there’s no neat, well-documented association between selenium deficiency and the Ebola virus, but the evidence strongly suggests one…
The first comes from the recent dramatic discovery that a selenium deficiency in a person or animal triggers a mutation in the coxsackievirus. The common form of this virus is generally benign, causing symptoms no more serious than a common cold or sore throat. The coxsackievirus mutation, however, attacks heart tissue, causing Keshan disease (a type of cardiomyopathy) and heart failure. (Sound familiar? Could this by why high reinfection- selenium depletion from first round increases susceptibility ?)
In China, Keshan disease is known to be associated with selenium deficiency. But because of the seasonal nature of Keshan disease, researchers suspected that an infectious microorganism was also involved. That’s when they turned up the coxsackievirus, which also infects an estimated 20 million Americans annually…
The coxsackievirus in animals eating a selenium-rich diet did not mutate. However, the mutated virus could infect and be deadly to a person or animal eating adequate selenium. (Journal of Medical Virology, 1994;43:66-70 and Journal of Nutrition, 1994;124:345-58.)
During the 1990s Ebola Zaire outbreak, a Chinese doctor gave large oral doses to over 50 patients. Amazingly few died and many fully recovered. He states his only regret was not administering it IV to extremely ill people as he felt they would’ve likely recovered. His paper is available in Mandarin, haven’t found it in English.
None of this is medical advice, but merely information. Selenium is a trace mineral with direct affects on the thyroid. (Thyroid meds have been the #1 Rx for a number of years in the USA.) You can get too much and have bad side effects so use with care. You can check USDA maps to see if your area is selenium deficit.
I recently poked the hornets nest on Peak Prosperity by stating that masks do not work (at least as they are worn int the USA.) I presented a specific example of a small region where exponential rise in infection rate has been coincident with an equally exponential increase in mask usage as they became mandatory. Commentators on PP reacted with horror, “masks must work because I believe they do” and ‘you are dumber than pond scum’ for suggesting otherwise.
Is it possible for any health issue in the USA to not become a political drum for opposing sides to beat on?
Or can we agree that properly designed masks can provide a high level of protection if properly worn? And make them universally available?