For airborne infections social distancing of 2m is not going to be enough. I presume the new London mutation of Covid-19 is particularly infectious because it is airborne. Face masks are not very helpful if the virus is airborne.
Airborne transmission is infection spread through exposure to those virus-containing respiratory droplets comprised of smaller droplets and particles that can remain suspended in the air over long distances (usually greater than 6 feet) and time (typically hours).
I take this to mean that to avoid infection you must avoid the space occupied by an infected person by 2m or by (say) 2 hours. Social distancing then has physical and temporal components.
But which also means that following in the footsteps of an infected person (for example in the supermarket checkout) does not have the necessary temporal distancing. Ventilation only shifts the virus further doing the time it stays “alive”/active. While ventilation to the the outside (on a plane, for example) will be helpful, airflow within an enclosed space only increases the distance needed in space to avoid infection.
The k2p blog 