Predominant airborne transmission and insignificant fomite transmission of SARS-CoV-2 in a two-bus COVID-19 outbreak originating from the same pre-symptomatic index case

• Pan ChengUniversity of Hong Kong
• Kaiwei LuoHunan Provincial Center for Disease Control and Prevention
• Shenglan XiaoSun Yat-sen University
• Hongyu YangSun Yat-sen University
• Jian HangSun Yat-sen University
• Cuiyun OuSun Yat-sen University
• Benjamin John CowlingUniversity of Hong Kong
• Hui‐Ling YenUniversity of Hong Kong
• David S.C. HuiChinese University of Hong Kong
• Shixiong HuHunan Provincial Center for Disease Control and Prevention
• Yuguo LiUniversity of Hong Kong