The article explains that the current 2 metre social distancing rule is based on studies into how far respiratory droplets travel from the mouth. But these studies were carried out in the 1930s and focused on relatively large, heavy droplets that fall to the ground in a few seconds. Scientists can now detect much smaller droplets that can stay airborne for up to 12 hours while following airflows and potentially reaching much further than 2 metres.
As the picture so graphically illustrates, masks can play a key role in reducing the quantity of airborne droplets expelled by the infected, while simultaneously reducing the exposure of the healthy.
It’s a clear win/win situation from a science perspective.
If there is one person who could lay claim to inventing the use of masks as protection against infection then it is Dr Wu Lien-teh.
Dr Wu’s story is fascinatingly described in Masking for a Friend, where they explain that Dr Wu was instrumental in bringing in face masks to protect first medical staff and then the general population from the deadly Manchurian plague that swept china in 1910-11. This made him a popular hero as the plague receded, and it is likely that this success laid the groundwork for face masks being positively viewed in today’s Asia.
It may be the experience of mask wearing laws set during the Spanish flu pandemic of 1918 that is guiding the policy makers of today to play down the usefulness of masks.
According to Samuel Cohn, Professor of history at the University of Glasgow, masks were the least popular instrument against the virus with little belief in their effectiveness and great outrage at the imposition they caused.
In what we could classify as a step in the right direction…
the Government is now advising that people should aim to wear a face-covering in enclosed spaces where social distancing is not always possible and they come into contact with others that they do not normally meet, for example on public transport or in some shops.
Our plan to rebuild: The UK Government’s COVID-19 recovery strategy
It would be so much better if they made this a requirement – no facemask, no getting on a bus or entering a shop. Hopefully this is coming soon.
Support for mask wearing is growing rapidly. The Artificial Intelligence Company fast.ai has published an excellent post that lays out in a clear way some of the scientific research that supports the use of face masks to fight Coronavirus.
A particularily clear illustration is made by the infection rates of two Countries: European neighbours Austria and Czechia. They both implemented social distancing on the same day but Czechia went a step further and introduced mandatory mask wearing.