It's one of the first things that came in to place!!
Received a message last week from someone who said they may not be able to come to an (outside) event that night because they'd been in close contact with a friend who'd tested positive. They said they were booked in for a test and if the result came back negative in time then they'd come along?! Why don't people realise you need to isolate for 10 days from contact?
Sorry for ranting but I wonder if this is another reason it spreads?