1. 1Department of Microbiology, School of Medicine, University of Occupational and Environmental Health, Kita-Kyushu, Japan
2. 2Department of Bacteriology, Graduate School of Medical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka, Fukuoka 812-8582, Japan
3. 3Hirose Children's Clinic, 8-12 Nakanokouji, Saga, Saga 840-0833, Japan
4. 4Section of Clinical Laboratories, Preventive Center for Adult-Disease of Saga Medical Association, 2-15 Shinnaka-machi, Saga, Saga 849-0924, Japan
5. 5Department of Medical Microbiology, College of Public Health, University of the Philippines-Manila, Manila, Philippines
6. †Present address: Professor Emeritus, Kyushu University.