Tuberculosis

Overview

Tuberculosis is a contagious disease caused by Mycobacterium tuberculosis. The bacteria can spread from person to person through tiny droplets in the air when a person with active tuberculosis coughs, sneezes, sings, talks, or even breathes.

The majority of people infected with Tuberculosis do not become sick. People who have latent tuberculosis infection have tuberculosis bacteria in their bodies but are not sick and cannot spread the bacteria to others. People with a condition known as subclinical Tuberculosis do not show symptoms of tuberculosis but may be able to spread the bacteria. People with active tuberculosis disease, however, are sick and can spread the bacteria to others.

Both latent Tuberculosis infection and active tuberculosis can be treated. Without treatment, latent tuberculosis infection can progress to tuberculosis, especially in individuals being treated with immunosuppressants.. Untreated tuberculosis disease can cause severe illness or death. Tuberculosis is the leading cause of infectious disease deaths worldwide.

Signs and Symptoms

People with latent tuberculosis infection have no symptoms.

People with tuberculosis that affects the lungs may have the following symptoms:

• A persistent cough that may bring up blood or sputum (phlegm)
• Chest pain
• Weakness or fatigue
• Loss of appetite
• Weight loss
• Chills
• Fever
• Night sweats

Although tuberculosis usually affects the lungs, it can affect any part of the body, including the kidneys, spine, or brain. When tuberculosis affects other parts of the body, a person may have other symptoms.

Related Health Effects

Human Immunodeficiency Virus (HIV) and Tuberculosis

HIV weakens the immune system, increasing the risk of tuberculosis.  All people with HIV should get tested for tuberculosis infection.

Infection with both HIV and tuberculosis is called HIV/tuberculosis coinfection. In people with HIV/tuberculosis coinfection, latent tuberculosis is more likely to become active tuberculosis than in people without HIV.

In people with HIV and latent tuberculosis infection, treatment with medicines against HIV and against tuberculosis reduces the chances that latent tuberculosis infection will advance to active tuberculosis.

Worldwide, tuberculosis is the leading cause of death among people with HIV.

In the United States, where HIV medicines are widely used, tuberculosis is relatively uncommon in people with HIV. However, it still affects some people with HIV especially those who are not on HIV treatment.

Diagnosis

A doctor may use one or more of these tests to identify latent tuberculosis infection or active tuberculosis:

• Blood test (Interferon-Gamma Release Assay)
• Sputum (phlegm) analysis
• Tongue swabs
• Tuberculin skin test
• Urine or tissue tests (outside of the United States)
• Chest X-ray or computed tomography (CT) scan

Causes and Risk Factors

Tuberculosis is caused by bacteria which spread when a person with active tuberculosis coughs, sneezes, sings, or talks.

Key risk factors include:

• HIV infection
• Weakened immune system
• Other health conditions, including diabetes, high blood pressure, malnutrition, and tobacco smoking
• Household or community contact with a person who has active tuberculosis disease
• Receiving antibody therapy to treat autoimmune disease

Prevention Guidance

Options for preventing tuberculosis disease include:

• Bacillus Calmette–Guérin (BCG) vaccine: The BCG vaccine is given to infants in many countries where tuberculosis is common to help prevent childhood tuberculosis. The BCG vaccine is not used for tuberculosis prevention in the United States.
• Treatment with HIV and Tuberculosis medicines: In people with HIV and latent tuberculosis infection, treatment with HIV and tuberculosis medicines reduces the chances that latent tuberculosis infection will advance to active tuberculosis.

Treatment and Management

Both latent tuberculosis infection and active tuberculosis disease can be treated. Tuberculosis is treated with a course of antibiotics that can last months to years. The choice of tuberculosis medicines and the length of treatment depend on whether a person has latent tuberculosis infection or tuberculosis and whether they have drug-resistant tuberculosis.

It is important to take all tuberculosis medicines exactly as prescribed. Missing doses or stopping treatment early can increase the likelihood of developing drug-resistant tuberculosis.

HIV/Tuberculosis Coinfection

People with HIV/tuberculosis coinfection should be treated for both HIV and tuberculosis. When to start treatment and what medicines to take depends on a person’s individual circumstances. Taking certain HIV and tuberculosis medicines at the same time can increase the risk of drug-drug interactions and side effects. People being treated for HIV/tuberculosis coinfection should be carefully monitored by their healthcare providers.

Find Clinical Trials

Clinical trials uncover better ways to prevent, diagnose, treat, and understand diseases and conditions. To ensure results apply to everyone, volunteers of all ages, sexes, and backgrounds, including both healthy individuals and those with specific medical conditions, are needed. Find clinical trials on tuberculosis.

Research Information

The National Institutes of Health (NIH) is the largest public funder of biomedical research in the world. NIH invests most of its budget in medical research seeking to enhance life and to reduce illness and disability. NIH-funded research has led to breakthroughs and new treatments helping people live longer, healthier lives, and building the research foundation that drives discovery.

NIH supports research to:

• Better understand tuberculosis biology, immune responses, and drug resistance
• Improve diagnosis of tuberculosis by developing faster and more accurate methods to find early infection, identify drug-resistant strains, and track the spread of tuberculosis in a community
• Develop or improve tuberculosis vaccines, including vaccines effective before and after exposure to to tuberculosis bacteria for adolescents and adults
• Improve tuberculosis treatment with new therapies, preventive treatment, and shorter treatment regimens

Find NIH-funded research projects using NIH RePORTER, a searchable database of current and past research projects supported by NIH and other federal agencies.