Despite a zero-Covid policy, cases of the coronavirus have reached a record level in Hong Kong, with 625 reported in the space of a day. It was the third day in a row that the authorities have reported a record number of infections, they said on Tuesday. Hong Kong, a city of 7 million people, recorded almost no cases for some time but the figures began to rise again at the end of December when two flight attendants who broke health rules introduced the virus again, according to reports. The number of cases has risen rapidly in recent days after the health authorities were unable to track the s…