Why are other countries wearing face masks?
For years westerners have viewed the far eastern face mask wearers with bemusement. Why did they wear them? Was it exposure to polluted streets and high-density city living? None of us took infection transmission as a plausible or sensible reason to don a face mask. But then we had not dealt with SARs in the west.
What a difference 3 months can make
Now a growing body of authorities, governments, and health officials are coming round to suggesting face masks as a crucial part of the relaxing of social distancing restrictions, and here's why...
The spread of infectious diseases through social networks has been studied extensively. From these studies, it is known that the spread of a virus will slow down or even stop altogether as mobility decreases at key ‘nodal points’.
Nodal points are places where lots of people gather, such as shops, restaurants, and public transport hubs. That's how closing down these works to slow the spread of the virus. It's where we are currently at in the UK. Allowing the currently infected population to incubate and develop Covid-19 while preventing them from spreading the infection to others in the period before they become seriously ill, or recover.
New modelling studies by the Aalto University in Helsinki looking specifically at Coronavirus droplet spread from coughing in confined indoor spaces, the example they modelled were supermarket aisles, and the findings suggested that a cough can produce particles which remain airborne for several minutes, and spread far further than 2 meters.
Their advice, “First of all, don’t go there if you don’t need to go there. If you need to go there, only go as seldom as possible. And number three: stay there as short a time as possible.
So where do face masks fit in with reducing this risk?
Simple, they catch droplets being coughed out to a large degree. But here is the problem in the authorities making the leap to advising widespread use of face masks in public places in the UK, The science does not exist to prove the point that the excretion of the virus is effectively reduced by standard masks, studies have only looked at the reduced inhalation advantages, which are minimal.
So we need to look to China and South Korea for large demographic data and start modelling behaviours that will enable the release of the lockdown while keeping the risks of transmission in key nodal points to below R1.
That means everyone wearing face masks in public places.