Role of Vitamin D in Innate Immunity to Tuberculosis

The investigators proposed a pilot study preparatory to developing a randomized trial of vitamin D for the prevention of TB infection. The specific aims are presented below:

1. To recruit subjects, obtain consent, distribute vitamin D supplements to the children in the schools, obtain blood samples and transport them to the United States. 2. To test the hypothesis that daily vitamin D supplementation will increase plasma levels of 25(OH)D, and restore TLR-induced antimicrobial activity in monocytes/macrophages tested in vitro.