Friday, August 7, 2020

Masks: Data and Opinions in the US and Europe


There is a lot of published evidence that surgical masks, which are equivalent to dust masks, and are basically the same as the cloth masks we are now wearing, provide little or no protection to the wearer against respiratory viruses.

Current dogma is that they are supposed to protect others from your exhaled viruses and secretions.  While there is no reliable evidence that they do so, it makes sense that they trap your 'globs' of saliva. Then the globs are slowly released as smaller particles, back into your airway as well as out to others'.  


Possibly masks provide a modicum of protection to the wearer, but they do not provide much.  Too many studies (over ten) have shown this. 


While the N95 masks do protect the wearer, the data showing this relied on doctors and nurses using them ONCE, for one patient, going into their room (usually a negative pressure room, which itself reduces viral and bacterial counts) ONCE.  BRIEFLY. Then the 75 cent mask is thrown away.


The masks that were effective were absolutely dry, the level of mask contamination, if any, was low grade, and the healthcare workers knew where the contamination might be coming from.  They did not wear the masks for long periods and expect them to prevent aerosol (aka tiny particle) transmission, which might be coming from any direction.  They did not fiddle with the masks to improve comfort, because they probably only wore them for, say, 5 minutes at a time.  They did not contaminate their fingers by repetitively taking them on and off, as I no doubt did when I shopped at half a dozen stores yesterday.


Also, hospitals are required to 'fit test' employees with the masks.  You are tested with a visible gas, to ensure you maintain a tight fit around the entire mask-skin margin.  If air leaks in around (rather than just coming through) the mask, the mask is not expected to work.  People with beards are considered unable to use N95 masks correctly.


Governments had to "do" something, so they imposed masks.  It is a visible symbol of governments assisting in Covid prevention, and a symbol that we, as individuals, are sharing in a mutual assistance effort.  


Does masking cause harm?  It probably reduces the level of activity that is possible for those with substantial heart or lung disease.  It is a problem for those with claustrophobia and some other types of anxiety.  There are reports of other medical problems, but since universal masking, especially outdoors, has never happened before, there is not a lot of reliable data.


The mask gives us the desperately sought sense that we are not powerless against the ravages of this virus.  

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Remember, back in late February, the CDC advised against wearing facemasks to prevent Covid. Later, CDC changed its tune.

What is Going on in the Rest of the World?


“All these countries recommending face masks haven’t made their decisions based on new studies,” said Henning Bundgaard, chief physician at Denmark’s Rigshospitale, according to Bloomberg News. (Denmark has since updated its guidelines to encourage, but not require, the use of masks on public transit where social distancing may not be possible.)  
Denmark is not alone.
Despite a global stampede of mask-wearing, data show that 80-90 percent of people in Finland and Holland say they “never” wear masks when they go out, a sharp contrast to the 80-90 percent of people in Spain and Italy who say they “always” wear masks when they go out.
Dutch public health officials recently explained why they’re not recommending masks.
"From a medical point of view, there is no evidence of a medical effect of wearing face masks, so we decided not to impose a national obligation," said Medical Care Minister Tamara van Ark.
Others, echoing statements similar to the US Surgeon General from early March, said masks could make individuals sicker and exacerbate the spread of the virus.
“Face masks in public places are not necessary, based on all the current evidence,” said Coen Berends, spokesman for the National Institute for Public Health and the Environment. “There is no benefit and there may even be negative impact.”
In Sweden, where COVID-19 deaths have slowed to a crawl, public health officials say they see “no point” in requiring individuals to wear masks.
“With numbers diminishing very quickly in Sweden, we see no point in wearing a face mask in Sweden, not even on public transport,” said Anders Tegnell, Sweden’s top infectious disease expert.
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Wearing a mask helps us feel we have some control in this crazy, upside down world that we now inhabit. It is a talisman, and a badge of solidarity with our fellow humans.  It comforts us, making us feel safer. And in our heightened surveillance state, it often defeats facial recognition algorithms.  But it probably does very little else.

UPDATE:  From the BBC:
Fifty million face masks bought by the UK government in April will not be used in the NHS because of safety concerns. The government says the masks, which use ear-loop fastenings rather than head loops, may not fit tightly enough.They were bought for NHS England healthcare workers from supplier Ayanda Capital as part of a £252m contract.Ayanda says the masks met the specifications No 10 had set out. The PM said he was "disappointed" that any protective kit should be unfit for use.
UPDATE:  More information on making an effective mask from ConsumerLab can be found here.  Also, CL writes
An analysis of rates of growth of COVID-19 infection in U.S. states found that the mandated use of masks in public issued by 15 states in April and May, 2020 was associated with a decline of about 1% in the daily COVID-19 growth rate within the first week of the mandates and a 2% decline 21+ days after mandates were issued.

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