Those clever people at WHO have done the maths! A meta-analysis of 172 studies has led to the conclusion that “Transmission of viruses was lower with physical distancing of 1 m or more, compared with a distance of less than 1 m
We found evidence of moderate certainty that current policies of at least 1 m physical distancing are probably associated with a large reduction in infection, and that distances of 2 m might be more effective, as implemented in some countries. We also provide estimates for 3 m. The main benefit of physical distancing measures is to prevent onward transmission and, thereby, reduce the adverse outcomes of SARS-CoV-2 infection. Hence, the results of our current review support the implementation of a policy of physical distancing of at least 1 m and, if feasible, 2 m or more.”
There is also comment regarding the importance of face masks and eye protection. This part of the message seems to be slipping past. “Protect your eyes too!