1. Microbiology unit; Department of Laboratory Medicine; Jigme Dorji Wangchuck National Referral Hospital; Thimphu Bhutan
2. Department of Surgery; Jigme Dorji Wangchuck National Referral Hospital; Thimphu Bhutan
3. Department of Medicine; Baylor College of Medicine; Houston TX USA
4. Massachusetts General Hospital; Harvard Medical School; MGH Gastroenterology Associates; Harvard University; Boston MA USA