1. Department of Health; Tuberculosis and Chest Service, Centre for Health Protection; Hong Kong China
2. Stanley Ho Centre for Emerging Infectious Diseases; The Chinese University of Hong Kong; Hong Kong China
3. Respiratory Medical Department; Kowloon Hospital; Hong Kong China
4. Respiratory Medical Unit; Ruttonjee Hospital; Hong Kong China
5. Tuberculosis and Chest Unit; Grantham Hospital; Hong Kong China