1. Interdisciplinary Program of Medical Microbiology; Graduate School; Chulalongkorn University; Bangkok 10330 Thailand
2. Department of Pathology & Immunology; Baylor College of Medicine; Houston TX 77030 USA
3. Department of Pathology; Texas Children's Hospital; Houston TX 77030 USA
4. Department of Physiology; Faculty of Medicine; Chulalongkorn University; Bangkok 10330 Thailand
5. Department of Pathology; Faculty of Medicine; Chulalongkorn University; Bangkok 10330 Thailand
6. Department of Microbiology; Faculty of Medicine; Chulalongkorn University; Bangkok 10330 Thailand