Targeted viral surveillance of transit passengers at just two major aviation hubs, Hong Kong and the United Arab Emirates, could speed global detection of new variants by about three days, a university study has found. Professor Leo Poon Lit-man, chair of public health virology at the University of Hong Kong (HKU), said on Wednesday that the approach would help authorities stay ahead of emerging threats. “Strengthening local surveillance in all regions remains the foundation of global health...