1. Center for Infectious Diseases, West China Hospital, Sichuan University, Chengdu, 610044, PR China
2. Department of Infectious Disease, People’s Hospital of Aba Tibetan & Qiang Autonomous Prefecture, Aba State, 624099, PR China
3. Department of Infectious Disease, The People’s Hospital of Jianyang City, Jianyang, 641499, PR China