There are several ways people can protect themselves against infection by tuberculosis (TB) bacteria. Most importantly, people should avoid contact with people known to be infected with TB. Healthcare workers or anyone caring for people infected with TB should wear protective masks while interacting with the infected person.

Anyone at risk of contracting TB should be regularly tested for the presence of TB bacteria. This may facilitate early treatment and cure of the disease, and help prevent its spread to others. High-risk populations that should be regularly tested include:

• Patients with HIV or AIDS
  
  
• Anyone with medical conditions or on medications that impair their immune system
  
  
• Older adults
  
  
• People born in countries with high rates of TB
  
  
• Substance abusers

Public health authorities can help lower TB rates in communities by regularly testing people in high-risk groups and offering treatment for people with latent TB (when dormant TB bacteria are present in the body). This may be especially helpful for people who live or work in poverty or who are otherwise not able to access appropriate medical care.

There is currently no effective vaccine against TB that is available in the United States. Some countries, especially those that have high rates of TB infection, use a vaccine for TB called Bacille Calmette-Guerin (BCG). This vaccine is not commonly used in the United States because of the low prevalence of TB and the fact that it does not guarantee protection against TB in adults. Additionally, the BCG vaccine uses a live version of TB bacteria that interferes with testing results and has been known to cause disease in people with impaired immune systems.

However, the BCG vaccine may be recommended for certain groups, such as healthcare workers who interact with TB patients, and children who live with infected adults. Scientists are currently developing a vaccine for TB that may be used in people at high risk of contracting TB, such as patients with autoimmune disorders.

People who have been diagnosed with active TB (the disease-causing infection) can prevent its spread by taking the following measures:

• Staying indoors in a well-ventilated room and reducing contact with other people while contagious.
  
  
• Covering the mouth and nose with a tissue when coughing or sneezing and then immediately disposing of the tissue.
  
  
• Taking the entire course of all prescribed medications, as recommended by the patient’s physician.

Active TB remains contagious for at least two weeks after TB medication is started. People diagnosed with active TB should limit their contact with others until a physician indicates it is safe to resume contact.