The Chinese woman was among 250 guests at the UK Bus Summit at the QEII Centre in Westminster on Monday – three days before heading to Lewisham Hospital in an Uber. Public Health England has since sent a letter to everyone who attended the event, warning them of the risks of contamination. They said: “While the degree of contact you may have had with the case at the summit is unlikely to have been significant, we are taking a precautionary approach and informing you.”