This study will assess the safety of a Bacillus Calmette-Guérin (BCG) vaccine against tuberculosis (TB) and will evaluate if giving the vaccine by mouth, injection, or by both methods produces greater results. BCG vaccine and/or placebo (substance containing no medication) will be given by mouth and/or by injection into the skin. This study, conducted at Saint Louis University, will enroll 60 (up to 80) healthy volunteers, 18-40 years old, who are negative for a TB test (QuantiFERON®-Gold) and human immunodeficiency virus (HIV). Study procedures will include a physical exam; review of TB exposure history and medical history; collection of multiple samples of blood, urine, stool, tears, and nose fluid; and skin and blood tests for TB. Volunteers may participate for about 24 months.