1. Recent immigrants (< 5 years) from countries with a high prevalence of tuberculosis (eg, Asia, Africa, Latin America).
2. HIV-negative injection drug users.
3. Mycobacteriology laboratory personnel.
4. Residents of and employees in high-risk congregate settings: correctional institutions; long-term care facilities; hospitals and other health care facilities; residential facilities for HIV/AIDS patients; and homeless shelters.
5. Persons with medical conditions that increase the risk of progression to tuberculosis disease: gastrectomy, ≥ 10% below ideal body weight, jejunoileal bypass, diabetes mellitus, silicosis, advanced chronic kidney disease, some hematologic disorders, (eg, leukemias, lymphomas), and other specific malignancies (eg, carcinoma of the head or neck and lung).
6. Children younger than 4 years or infants, children, and adolescents exposed to adults at high risk.