1. Department of Bacteriology II; National Institute of Infectious Diseases; Tokyo
2. Department of Pediatrics; Konan Kosei Hospital; Konan
3. Department of Pediatrics; St. Marianna University School of Medicine; Kawasaki
4. Denka Seiken Co. Ltd; Tokyo
5. Section of Pediatrics; Department of Medicine; Division of Oral & Medical Management; Fukuoka Dental College; Fukuoka
6. Department of Bacteriology; Nagoya University Graduate School of Medicine; Nagoya Japan