Department of Infectious Disease,Children's Hospital,Zhejiang University School of Medicine,3333 Binsheng Road,Binjiang District,Hangzhou 310052,China

Clinical Research Unit,Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China

Beijing Pediatric Research Institute,Beijing Children's Hospital,Capital Medical University,Beijing,China

Department of Pediatric Pulmonology,West China Second University Hospital,Sichuan University,Chengdu,China

Department of Pediatric Pulmonology,the Second Affiliated Hospital & Yuying Children's Hospital,Wenzhou Medical University,Wenzhou,China

Department of Infectious Disease,Anhui Provincial Children's Hospital,Hefei,China

Department of Pediatrics,the Second Hospital of Hebei Medical University,Shijiazhuang,China

Department of Pediatrics,Xijing Hospital,the Fourth Military Medical University,Xi'an,China

Department of Infectious Disease,Guangzhou Women and Children's Medicine Center,Guangzhou Medicine University,Guangzhou,China

Department of Pediatrics,Tongji Hospital,Tongji Medical College,Huazhong University of Science and Technology,Wuhan,China

Department of Respiratory Disease,Beijing Children's Hospital,Capital Medical University,Beijing,China

Department of Pediatric Respiratory,Shengjing Hospital of China Medical University,Shenyang,China

Respiratory Department,Children's Hospital Affiliated to Capital Institute of Pediatrics,Beijing,China

Department of Clinical Epidemiology,Aarhus University,Aarhus,Denmark

Department of Respirology,Children's Hospital of Soochow University,Suzhou,China

Department of Respiratory,Children's Hospital of Shanghai,Children's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine,Shanghai,China

Department of Infectious Disease,Hainan Women and Children's Medical Center,Haikou,China

Department of Infectious Disease,Children's Hospital of Chongqing Medical University,Chongqing,China

Department of Respiratory,Children's Hospital of Nanjing Medical University,Nanjing,China

Department of Infectious Diseases,Children's Hospital of Fudan University,399 Wanyuan Road,Minhang District,Shanghai 201102,China

Department of Respiratory Diseases,Children's Hospital,Zhejiang University School of Medicine,3333 Binsheng Road,Binjiang District,Hangzhou 310052,China