Cloth masks are NOT enough to stop the spread of Covid-19 without social distancing
Wearing a cloth mask may not shield the user from coronavirus because too many infected droplets can slip through, a study has claimed.
Scientists at New Mexico State University, in the US, studied five types of face coverings including cloth masks and surgical grade N95 masks.
They found that while all masks blocked at least 95 per cent of droplets from coughs and sneezes - there was still a risk of the disease being passed on.
Although cloth masks stopped 96.4 per cent of sneeze droplets at a distance of six feet, they still let more than 1,000 through - which the scientists said could carry enough virus particles to trigger an infection.
'Wearing a mask will offer substantial, but not complete, protection to a susceptible person,' said Dr Krishna Kota, an associate professor at the university who led the research.
The science behind mask-wearing was hazy at the start of the pandemic and authorities in the UK and other countries hesitated to recommend wearing them.
The World Health Organization did recommend masks until June 8, and then only for people over 60 and those with underlying health conditions.
In Britain, face coverings were first brought in for public transport in June, and later for shops and other indoor spaces in July. In the US regulations vary across the country, with some states setting up rules as early as April but others resisting making masks mandatory.
The general consensus now is that masks may offer only limited protection to the people wearing them, but they are quite good at stopping people spreading the disease if they have it without knowing, because they catch their breath.
Scientists have also suggested that masks could reduce severity of disease by exposing people to the virus in small doses, but this hasn't been proven.
'A mask definitely helps, but if the people are very close to each other, there is still a chance of spreading or contracting the virus,' said Dr Kota. 'It's not just masks that will help. It's both the masks and distancing.'
For the study, published in the journal Physics of Fluid, the team built a machine that mimics coughs and sneezes from humans. It uses an air generator to blow tiny liquid droplets, like those that would escape from a nose or a mouth.
The machine was tested on five different types of masks: an N95 mask, a surgical mask, a cloth mask, a two-layer cloth mask and a wet two-layer cloth mask.
The researchers say wetting a mask could help because the material’s fibers will expand, reducing the pore size accessible for droplets to get through.
Two glass square tubes were joined with a mask tightly fit between them and a camera lens to capture the number of droplets.
Each of the masks were able to block most of the droplets with the best-performing being the N95, which blocked 100 percent of droplets.
Meanwhile, the worst was the regular cloth mask, which only blocked 96.4 percent of the droplets from getting through.
However, at distances of less than six feet, letting in around three percent of droplets could be enough to make someone ill.
Studies have shown that the average infection threshold for COVID-19 is 1,000 virus particles, inhaled either all at once or on separate occasions.
In addition, a single sneeze has the potential to carry up to 200 million virus particles.
The cloth mask let through more than 1,000 sneeze droplets, each of which could have millions of virus particles.
The two-layered cloth mask with a PM2.5 filter let through more than 600 sneeze droplets.
This means that if someone wearing one of these masks is close to an infected individual, enough droplets could escape to make them contract COVID-19.
'Without a face mask, it is almost certain that many foreign droplets will transfer to the susceptible person,' Kota said.
'Wearing a mask will offer substantial, but not complete, protection to a susceptible person by decreasing the number of foreign airborne sneeze and cough droplets that would otherwise enter the person without the mask.
'Consideration must be given to minimize or avoid close face-to-face or frontal human interactions, if possible.'
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'Balancing act': The problem with COVID mandates
Julie Leask comments from Australia:
Recent developments in the pandemic such as vaccines and the outbreak of COVID-19 on Sydney's northern beaches have prompted calls for governments to mandate public health measures such as vaccination or mask wearing to control the virus.
Mandating certain behaviours to prevent the spread of infectious diseases can be an effective measure in public health. It can bring about behaviour change at-scale and remove the burden on individual decision making. But mandates come with downsides which are often overlooked.
Mandates will always carry a penalty for non-compliance: a fine for not wearing a mask or denial of childcare or family payments for the incompletely vaccinated child. These are serious consequences, particularly for people experiencing disadvantage, who themselves are already more likely to be economically or socially affected by pandemic measures. Yet it is those experiencing disadvantage who are more likely to be fined for COVID-19 rule compliance breaches. For example, in April, Sydney’s poorer Fairfield Local Government Area had just 0.98 per cent of cases but 3.7 per cent of infringements while richer Waverly had 6.7per cent of cases but just 0.79 per cent of infringements.
Mandates lead to interpersonal conflict at the point of enforcement. This is a particular problem if those with roles in implementing the requirement also provide the service because it can undermine the relationship between citizen and service. For example, the driver who turns away unmasked people boarding a bus taking them to an appointment or a doctor refusing to grant a medical exemption for an unvaccinated child will inevitably end up dealing with distressed and sometimes abusive people.
Mandates bring a tonal shift in pandemic control – from solidarity to enforcement. Rules can offer support – it’s sometime easier to just be told to do something. A few people only respond to rules. But they can also undermine intrinsic motivations towards the public co-operation more generally, making behaviour more about what I can and can’t do than what I should do for others. For long-haul behaviours like pandemic control ones, intrinsic motivation is better because it carries across a number of minute and everyday behaviours impossible to police.
Mandates should bring a meaningful additional level of compliance to controlling the spread of a disease. Right now in NSW, some commentators have called for mandatory masks for all of Sydney, at a time when the state is recording reductions in locally acquired new cases, decreasing from a high of 38 on December 19 to 8 cases on December 23. The most important control measures have been rapid identification and isolation of cases and contacts, helping bring this outbreak under control, like NSW did in July after a cluster began in south western Sydney. In Victoria, mandatory masks were hoped to be enough to bring a rising outbreak under control. But within a week it was clear that a prolonged lockdown was also needed.
Mandates require significant resourcing and attention from government departments. Legislation needs to be carefully drafted to account for the range of implications they will bring. There should be a threshold for determining what is, and is not, required and means for determining compliance. This is easier for policing the wearing of masks. For vaccination, Australia uses a national register to determine compliance. But recording error or failure to enter the data means some fully compliant families have wrongly lost family assistance payments under the No Jab No Pay. Mandates need good systems in place to be fair and feasible.
Most of these issues can be justified and managed if the benefits of mandating a behaviour are deemed to outweigh the risks. Right now in Sydney, mask wearing when one cannot distance is strongly recommended. But a mandate to do so would be disproportionate when considering the downsides along with their limited role right now in controlling COVID-19. If we are unlucky enough to see established transmission across Sydney or any other region, that might change.
For now, the measures announced on Wednesday are reasonable – limited numbers inside homes with restrictions around movement of people on the northern beaches where the cluster remains focused. We must remain focused on the most effective measures – testing and isolating if symptomatic, rapid contact tracing, quarantining of contacts, and limiting large gatherings, vigilant hand and respiratory hygiene and wearing masks when social distancing is not possible. Venues need to systematically ensure all customers accurately log their details when entering.
Mandating individual actions to prevent infectious disease spread should only be in place when the shift to mandating will be effective and carries little risk, the requirement is reasonable, feasible to enforce, and well justified. Taken together, this is about weighing the benefits of an action against its risks – something Australians have become adept at doing in 2020 when it comes to infectious diseases.
https://www.smh.com.au/national/balancing-act-the-problem-with-covid-mandates-20201222-p56pnl.html
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Having the media on your side makes a big difference
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IN BRIEF
Biden names Bruce Reed, fiercely opposed by the "Squad," as deputy chief of staff (Fox News)
Team Biden gently walking back election-year immigration promises (Washington Examiner)
Newsmax, OAN, and Trump campaign sued by voting systems worker who says false claims led to death threats (AP)
Georgia Runoff: Raphael Warnock's wife told officer that her husband is "a great actor" after domestic dispute (Fox News)
Government & Politics
Sen. Rand Paul's "Festivus Report" reveals $54 billion in tax dollars was "totally wasted" (Fox News)
Tulsi Gabbard justifiably rips young Congress members for taking vaccine before elderly (NY Post)
D'oh! Biden calls reporter asking about Hunter Biden a "one-horse pony" (Washington Examiner)
Washington Post depicts Republicans as rats in editorial cartoon eerily similar to anti-Semitic Nazi propaganda (Not the Bee)
Acting defense secretary accepts Inclusion Board's 15 woke recommendations (Defense.gov)
Walmart sued by the Justice Department for allegedly fueling opioid crisis (CBS News)
November existing home sales fall 2.5%, following record summer (AP)
In final reading, GDP increased at record 33.4% annual rate in third quarter (Washington Examiner)
Detroit suing Black Lives Matter activists for "civil conspiracy" (Fox News)
Face masks significantly reduce brain's ability to recognize people (StudyFinds)
Policy: How the Centers for Disease Control went woke (Free Beacon)
Policy: Maximizing equality of opportunity is the only way to avoid lowering standards (City Journal)
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