Bacille Calmette-Guérin (BCG) Immune Response Study

This study is investigating how the BCG vaccine (the tuberculosis vaccine often given to newborns) affects the immune system in babies. Researchers want to understand how the vaccine strain and the age at which babies are vaccinated affects the type and strength of the immune response, which may relate to how well the vaccine protects them. You may be eligible if: - Your baby is a healthy full-term newborn - Your baby is between 1 day and 2 months old You may NOT be eligible if: - There is a family history of immune deficiency disorders - The mother has HIV - The mother has active tuberculosis (TB) Talk to your doctor about whether this trial might be right for you.