1. Department of Infection Control Science, Faculty of Medicine, Juntendo University, 113-8421 Tokyo
2. Kotobiken Medical Laboratories Inc., 305-0804 Ibaraki
3. Nikken Bio Medical Laboratories Inc., 613-0046 Kyoto
4. Division of Pediatrics, Fukuoka National Hospital, 811-1394 Fukuoka
5. Department of Infectious Diseases, Kitasato University School of Medicine, 228-8555 Kanagawa, Japan