what this shows me is that , if no one else has tested positive then what a waste of time these stupid face masks are !

I'm trying hard to work out your logic. There is strong evidence that wearing a face mask reduces the chances of someone with a respiratory infection transmitting it as well as good evidence that it will reduce the chances of catching an infection.

As  you're so confident masks have no role in preventing the transmission of infection, I take it you're happy for the surgeon (and the rest of the theatre staff) not to bother wearing them when they do an operation on you.

Oh and didn't a support staff member test positive yesterday? We don't know who they've been in close contact with,  possibly not wearing a mask.