BEIJING, China (AFP) — The Chinese city of Xi’an began testing millions of residents for the coronavirus on Tuesday after the detection of more than 40 new cases raised concerns of wider transmission ahead of a busy travel season. China, where the virus was first detected, has slowed new cases to a trickle since the middle of last year through border restrictions, targeted lockdowns and lengthy quarantines as it pursues a zero-Covid strategy. But the […]