There are eight signs that you might have had coronavirus Covid-19 a month before it was previously thought to have arrived in the UK.Research carried out by Oxford University's Evolutionary Ecology of Infectious Disease group suggests that Covid-19 may have reached the UK by mid-January at the latest.The scenario is one of the several the researchers presented as possible, and goes against previously understood death rates.In the non-peer reviewed study they suggest that the coronavirus, like many emerging infections, may have spread invisibly for a month before its effects became clear at the end of February.If the Oxford researchers are right, then as much as half of the country's population may already have been infected.Many people