1. Department of Microbiology, Chitwan Medical College, Bharatpur, Nepal
2. Department of Environmental and Preventive Medicine, Oita University Faculty of Medicine, Yufu, Oita, Japan
3. Global Oita Medical Advanced Research Center for Health, Yufu, Oita, Japan
4. Department of Medicine, Gastroenterology and Hepatology Section, Baylor College of Medicine, Houston, TX, USA
5. Borneo Medical and Health Research Centre, Universiti Malaysia Sabah, Kota Kinabaru, Malaysia