Tuberculosis
a person coughing while a doctor examines them, a lung x-ray, and a doctor writing a prescription.

Tuberculosis

En Español

Tuberculosis (TB)

Tuberculosis (TB) is a disease caused by germs spread from person to person through the air. TB usually affects the lungs but can also affect other body parts, such as the brain, kidneys, or spine. Not everyone infected with TB germs becomes sick. As a result, two TB-related conditions exist: latent TB infection (or inactive TB) and TB disease.

Tuberculosis Fact Sheets

Only People with Active TB can Spread it to Others

Knowing that a person exposed to TB cannot spread the germs to other people right away is important. Only people with active TB disease can.

TB germs are more likely to spread indoors or in places with poor air circulation than outdoors.

TB germs are not spread by:

  • Shaking someone’s hand
  • Sharing food or drink
  • Touching bed linens or toilet seats
  • Sharing toothbrushes
  • Kissing

TB Can Be Contagious

TB is caused by a germ called Mycobacterium tuberculosis. TB germs are spread through the air from one person to another. The TB germs are put into the air when a person with active TB disease of the lungs or throat coughs, speaks, or sings. People nearby may breathe in these germs and become infected. Infection usually occurs when a healthy person and a person with active TB disease are in close contact in an enclosed space with little fresh air and over a long period. Even under these conditions, people often do not become infected.

TB is NOT spread by shaking someone’s hand, sharing food or drink, touching bed linens, toilet seats, or tissues, sharing toothbrushes, or kissing. It can only be spread by breathing air containing TB germs.

Inactive TB Infection

A person’s body may kill all the TB germs on its own. If the TB germs remain alive but inactive in the body, this is known as TB infection. People with TB infection are not sick and cannot make others sick, but they may become ill if not treated.

A Person With Inactive TB

  • Has a small amount of TB germs in their body that are alive but inactive.
  • Has no symptoms and does not feel sick.
  • Cannot spread TB germs to others.
  • Usually has a positive TB blood test or TB skin test indicating TB infection.
  • Has a normal chest x-ray and a negative sputum smear.
  • Needs treatment for inactive TB to prevent active TB disease.

Active TB Infection

When the body cannot suppress the infection, the person may feel sick and can infect others—especially people they spend time with every day. This includes family members, friends, coworkers, or schoolmates. This is called active TB disease. People with active TB disease must receive treatment, or they will become very sick and can continue to infect others.

A Person With Active TB Disease

  • Has a large amount of active TB germs in their body.
  • Has symptoms and feels sick.
  • May spread TB germs to others.
  • Usually has a positive TB blood test or TB skin test indicating TB infection.
  • May have an abnormal chest x-ray, or positive sputum smear or culture.
  • Needs treatment for active TB disease.

Testing for Tuberculosis

There are two types of tuberculosis (TB) infection tests: the TB blood test and the TB skin test. A positive test result for TB infection means you have TB germs in your body. If you test positive for TB infection, your healthcare provider will do other tests to determine if you have inactive TB (also called latent TB infection) or active TB disease.

Getting Tested for TB Protects You and Your Community

Getting tested and treated for TB can protect you and everyone in your community.

You may need a TB test if you have:

  • Symptoms of TB disease
  • Spent time with someone who has active TB disease
  • Factors that put you at higher risk of developing active TB disease
  • Employment, school, travel, or immigration health screening requirements

You may need a TB test even if you do not feel sick. TB germs can live in your body for years without making you feel sick. This is called inactive TB. People with inactive TB do not feel ill and cannot spread TB germs to others.

TB Screening (Blood Test or Skin Test)

Anyone needing TB screening can contact their healthcare provider or Denver Public Health TB Clinic.

Preventing the Spread of TB

Contact Tracing

If you have active TB, your healthcare worker may ask about your contacts (the people you spent time with when you were able to spread TB germs) and conduct a contact investigation, also known as contact tracing. The information shared with a contact tracer will be kept confidential.

Contact tracing identifies people who have recently been in contact with someone diagnosed with an infectious disease. Contact tracing quickly identifies, assesses, and manages people exposed to a disease to prevent additional spread.

Once a person tests positive for a disease, they will be asked to list the people they have been in contact with and the places they visited during the period in which they were contagious. Boulder County Public Health or other contact tracers will contact the patient’s contacts and explain what precautions they need to take.

Contacts may include:

  • People in the household
  • Family members
  • Friends
  • Coworkers
  • Classmates
  • Neighbors
  • People within a social circle
  • People at places of worship (church, synagogue or mosque)
  • Anyone else who may have spent time with a patient while they were able to spread TB germs

Signs and Symptoms of TB

Symptoms of active tuberculosis (TB) disease depend on where the TB germs are growing in the body. Common symptoms of active TB include cough, chest pain, and coughing up blood or sputum (phlegm). People with inactive TB, also called latent TB infection, do not have symptoms of TB disease and cannot spread TB to others.

Active TB Disease

Symptoms of active TB disease depend on where the TB germs are growing in the body. TB germs usually develop in the lungs (pulmonary TB).

Active TB disease in the lungs may cause symptoms such as:

  • A bad cough that lasts three weeks or longer
  • Pain in the chest
  • Coughing up blood or sputum (phlegm) from deep inside the lungs

Other symptoms of active TB disease are:

  • Weakness or fatigue
  • Weight loss
  • Lack of appetite
  • Chills
  • Fever
  • Sweating at night

Symptoms of active TB disease in other parts of the body depend on the area affected:

  • Disease of the lymph nodes may cause a firm red or purple swelling under the skin.
  • Disease of the kidney may cause blood in the urine.
  • Meningitis (TB disease of the brain) may cause headaches or confusion.
  • Disease of the spine may cause back pain.
  • Disease of the larynx may cause hoarseness.

Inactive TB

People with inactive TB do not have symptoms of TB disease. However, without treatment, they can develop active TB disease and become sick.

Treating Tuberculosis

  • Both inactive tuberculosis (TB) (also called latent TB infection) and active TB disease can be treated.
  • It is essential to take and finish all TB medicines precisely as your healthcare provider recommends.
  • Completing treatment for inactive TB and active TB disease can protect you, your family, your friends, and your community.

Treatment Overview

Not everyone infected with TB germs becomes sick. As a result, two TB-related conditions exist: inactive TB and active TB disease. Both inactive TB and active TB disease can be treated.

Even though you may not feel sick, inactive TB can develop into active TB disease at any time and make you ill. If you have inactive TB, treating it is the best way to protect you from getting sick with active TB disease. If you have active TB disease, you can be treated with medicine.

TB germs are strong and can take a long time to die. It is important to take and finish all TB medicines precisely as your healthcare provider recommends.

Treatment Options

Several safe and effective treatment plans are recommended in the United States for inactive TB and active TB disease. A treatment plan (also called treatment regimen) for inactive TB or active TB disease is a schedule to take TB medicines to kill all the TB germs. Your treatment plan for inactive TB or active TB disease will include:

  • The types of TB medicines to take
  • How much medicine to take
  • How often to take TB medicines
  • How long to take the medicines
  • How to monitor yourself for any side effects of your TB medicine
  • The health care provider(s) who will support you through the treatment process.

You and your healthcare provider will discuss the best treatment plan for you.

Inactive TB

Treatment for inactive TB can take three, four, six, or nine months, depending on the treatment plan.

The treatment plans for inactive TB use different combinations of medicines that may include:

  • Isoniazid
  • Rifampin
  • Rifapentine

Tuberculosis Risk Factors

Anyone who has been exposed to TB can become ill with it. The risk of exposure is highest when spending time near someone with active TB disease.

You have a higher risk of being exposed to TB germs if you:

  • Were born in or frequently traveled to countries where TB is common, including some countries in Asia, Africa, and Latin America
  • Live or used to live in large group settings where TB is more common, such as homeless shelters, prisons, or jails
  • Recently spent time with someone who has an active TB illness
  • Work in places where TB is more likely to spread

You have a higher risk of developing active TB disease once infected if you:

  • Were recently infected with TB germs
  • Have a weaker immune system because of certain medications or health conditions such as diabetes, cancer, or HIV

Some people develop active TB disease soon (within weeks) after becoming infected before their immune system can fight the TB germs. Other people may get sick years later when their immune system becomes weak for another reason.

Contact Us


Tuberculosis Control

Main: 303-413-7523
Alejandro.perez@dhha.org


Location

Boulder
3482 Broadway
Map and Directions
Hours: 8 a.m. to 4:30 p.m.
Monday-Friday

Boulder County Public Health logo