"We think the epidemic is just about slowing in the UK right now," Ferguson told BBC radio.
He said a third or even 40% of people do not get any symptoms. He said perhaps 2% to 3% of the United Kingdom's population had been infected.
But Ferguson cautioned that the data was not good enough to make firm extrapolations.He said antibody tests were in the final stage of validation right now and could be hopefully ready to use in "days rather than weeks."