1. National Institute of Infectious Diseases; Musashimurayama-shi, Tokyo Japan
2. National Institute for Biological Standards and Control; Potters Bar, Hertfordshire UK
3. Fukuoka Dental College; Sawara-ku, Fukuoka-shi, Fukuoka, Japan
4. Present; Consultant, 24 the Approach, Milton Keynes MK8 8PA, UK