People still don’t seem to realise that a key factor in coronavirus infection is not just whether you are in contact with an infected person, but how long you are in contact.

Several times at the end of my weekly shop I have found myself at the till behind another customer who is wearing a mask, which is thoughtful, since, if they are infectious, they are less likely to pass this on, although masks are sadly less effective at protecting them from someone else’s infection.

But then they throw away the benefit by insisting on spending five or six minutes carefully sorting all their shopping into individual bags at the till, rather than putting it quickly back in the trolley and sorting it out at the car.

They double or triple the contact time during which they could pass or receive the infection.

Meanwhile, of course, a queue is building up behind them …

Adrian Tayler

Holly Bank