There seems to be a belief that lots of people have already had it means the same as a significant number of people have already had it
I would be surprised if even 1 in 100 people have had it already based on current deaths and tested positive numbers
If say 50000 have tested positive and that is only 10% of people who have it ( assuming only testing people who hospitalised ) it's only half a million out of a population of 72 million