If I have latent TB infection, how can I keep from developing active TB disease?

Antibiotics. If you are 35 or less, it is recommended to take prophylactic antibiotics. If you are older than 35, the risk of taking the antibiotic is higher and outweighs the benefits of taking it. Talk to your doctor.
Treatment. If you have latent TB infection, there is a 10% chance of developing active TB disease over your lifetime. The risk seems to be the highest in the first two years after the acquisition of infection, although in most cases it is hard to pinpoint the exact time of infection. Treatment for latent TB infection can eliminate this risk completely. So seek treatment from your local infectious disease doc.