Tuberculosis (TB)
Prevention
Avoid getting active TB
Active tuberculosis (TB) is an infection that is spreading in a person's body, and it is very contagious.
The World Health Organization (WHO) estimates that one-third of the world's population is infected with the bacteria that causes TB. To avoid getting an active TB infection:
- Do not spend long periods of time in stuffy, enclosed rooms with anyone who has active TB until that person has been treated for at least 2 weeks.
- Use protective measures, such as face masks, if you work in a facility that cares for people who have untreated TB.
- If you live with someone who has active TB, help and encourage the person to follow treatment instructions.
Prevent latent TB from becoming active
Usually, treatment with isoniazid for about 9 months or rifampin for 4 months can prevent a latent TB infection from developing into active TB. Treatment is recommended for anyone with a skin test that shows a TB infection, and is especially important for people who:
- Are known to or are likely to be infected with the human immunodeficiency virus (HIV).
- Have close contact with a person who has active TB.
- Have a chest X-ray that suggests a TB infection, and have not had a complete course of treatment.
- Inject illegal drugs.
- Have a medical condition or take medicines that weaken the immune system.
- Have had a tuberculin skin test within the past 2 years that did not show a TB infection but now a new test indicates an infection.
Can the TB vaccine help?
A TB vaccine (bacille Calmette-Guerin, or BCG) is used in many countries to prevent TB. But this vaccination is almost never used in the United States because:
- The risk of getting TB is low in the U.S.
- The vaccine is not effective in adults who receive it.
- The BCG vaccine may cause a tuberculin skin test to indicate a TB infection even if a person is not infected with TB. This complicates the use of the tuberculin skin test to check people for TB.
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| Author: | Maria G. Essig, MS, ELS | Last Updated: April 23, 2009 |
| Medical Review: | Caroline S. Rhoads, MD - Internal Medicine R. Steven Tharratt, MD, MPVM, FACP, FCCP - Pulmonology, Critical Care, Medical Toxicology | |
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