He is the vice-superintendent of National Cheng Kung University Hospital, and Professor of Department of Medicine, National Cheng Kung University, Tainan, Taiwan. His research interest includes antimicrobial stewardship, antimicrobial resistance, and bacterial infections, including Aeromonas, Klebsiella pneumoniae, and Clostridioides difficile infection. Epidemiology and clinical management of bloodstream infections in the community is another research focus. He joined several international surveillance of antimicrobial resistance programs and published more than five hundred articles in academic journals in the fields of infectious diseases, clinical microbiology, antimicrobial therapy, and HIV medicine.