Health Library

Tuberculosis in Children

Why Tuberculosis Is Still a Global Health Concern

TB remains one of the leading infectious causes of death worldwide. Millions of people are diagnosed each year, especially in parts of the world where access to healthcare is limited.

In the United States, TB is much less common. Still, some children develop TB each year, with most cases being latent (inactive) infection that is typically seen in higher-risk groups. Learning how TB spreads and how it is treated can help families feel more informed and reassured.

Contagiousness and Isolation

TB is only contagious in certain situations. A child with active TB in the lungs can spread TB through the air when they cough, sneeze or speak. TB that is not active (what we call latent TB infection) does not spread to others. TB also does not spread through touch, sharing food or touching surfaces.

When a child has active TB, steps may be taken for a short time to protect others and reduce the risk of spread. These may include:

• Isolation: The child staying in a special room with filtered air
• Contact tracing: Identifying people who may have been exposed to the child so they can be tested
• Directly observed therapy: Closely supervising the child taking their medicines to be sure they are taken correctly

What Causes Tuberculosis?

TB is caused by Mycobacterium tuberculosis bacteria. These bacteria spread through the air from one person to another, usually after close or long indoor contact with someone who has active TB disease in the lungs.

How Do You Get Tuberculosis?

TB spreads from one person to another when someone who has active TB coughs, sneezes, speaks or sings. The bacteria get released into the air and breathing in these bacteria can lead to infection. Children do not spread TB bacteria as easily as adults. Care needs to be taken to decrease the risk of getting TB from both adults and children.

Many people who are exposed do not become sick right away. In some cases, the bacteria stay inactive in the body for months or years. This is known as “latent TB infection.” Latent TB infection needs to be treated, as the bacteria can reactivate and cause active disease that becomes contagious to others.

Who Is at Higher Risk of Getting TB?

Some children have a higher risk of getting TB or becoming sick from it than others, especially if their immune system has trouble fighting infection.

Infants and young children are at higher risk because their immune systems are still developing. Children with certain medical conditions such as human immunodeficiency virus (HIV) or treatments that lower your immunity, such as cancer therapy or organ transplant, may also be at higher risk. Living in crowded or poorly ventilated spaces can increase the chance of exposure. Doctors consider these TB risk factors when deciding who should be tested or treated.

What are the Types of Tuberculosis?

There are different types of TB. The type affects symptoms and treatment, and whether TB can spread.

Latent Tuberculosis Infection (LTBI)

With latent TB infection, TB bacteria are in the body but not active. Children with latent TB infection do not feel sick and have no symptoms. They also cannot spread TB to others.

Even though a child feels well, treatment is important. Without treatment, latent TB infection can turn into active TB disease later in life that then becomes contagious.

Active Tuberculosis Disease

Active TB disease means the bacteria are active and causing illness. Children with active TB disease usually have symptoms and need treatment right away.

If the lungs are involved, active TB disease can spread to others through the air. TB can also affect other organs, which may cause different symptoms.

Pulmonary vs. Extrapulmonary Tuberculosis

Pulmonary TB affects the lungs and is the most common form of TB.

Extrapulmonary TB affects areas outside the lungs, such as the lymph nodes, bones or joints, brain or kidneys. You may hear doctors call this “TB outside the lungs.” 

What are Symptoms of TB?

Signs of tuberculosis depend on the type of TB and where it is in the body.

When TB affects the lungs (active pulmonary TB), children may have:

• A prolonged, chronic cough
• Chest pain
• Coughing up blood (hemoptysis)
• Fever
• Night sweats
• Fatigue
• Weight loss

When TB affects areas outside the lungs (extrapulmonary TB), symptoms vary and may include:

• Swollen lymph nodes (painless, firm lumps on neck, groin or chest)
• Bone or joint pain
• Headaches or other nerve symptoms such as numbness, tingling, burning pain and weakness in limbs
• Abdominal pain

How Is Tuberculosis Diagnosed?

Doctors use several tests to diagnose TB. The tests chosen depend on a child’s symptoms, age and risk factors.

TB Screening Tests (Latent TB Tests)

Screening tests look for TB infection even when a child feels well. These tests help find latent TB infection before it causes illness.

Tests may include:

• TB skin test – A small amount of tuberculin fluid is injected under the skin on the arm and checked a few days later for a hardened, raised bump.
• TB blood test, also called Interferon-gamma release assay (IGRA) blood test or the TB QUANTiferon blood test. A blood sample is checked in the lab for signs of TB.
• Sometimes another test called a TSPOT may be used.

A positive TB test shows the child has been exposed to TB, so doctors will follow a positive test with other tests. These will show if the child has latent TB or active TB.

Diagnostic Imaging

If your child has a positive TB test, their doctor will likely do imaging tests to look for signs of active disease. Imaging tests help doctors look at the lungs and other areas of the body. These tests may include a chest X-ray or, when more detail is needed, a CT scan.

Laboratory Testing

Lab tests help confirm active TB disease and guide treatment decisions. For these tests, the child coughs deeply to produce phlegm or mucus from the lungs (called sputum). If the child is too young to cough up sputum, they are typically admitted to the hospital with placement of a nasogastric (NG) tube that allows for a sample (called a gastric aspirate) to be collected and evaluated for TB. The sputum (or gastric aspirate) can then be tested in different ways to look for signs of TB. Different lab tests include:

• Sputum smear microscopy – The mucus is checked directly under a microscope. You get results very quickly (in about 24 hours).
• TB culture – Doctors put the mucus in a special container for several weeks to grow the TB bacteria. This test is considered the “gold standard” because it’s more accurate than the sputum smear test.
• Molecular testing – Doctors test the sputum for genetic signs of the TB bacteria. This testing is only approved for sputum and not gastric aspirates.
• Drug-resistance testing – Doctors use this genetic test to see which medicines might work best on your child’s TB.

What Are the Treatment Options for Tuberculosis?

Treatment depends on the type of TB and where it is in the body. Taking medicines exactly as prescribed is important for recovery and for preventing the spread of TB.

Latent TB treatment: If a child has latent TB infection, medicine is used to help prevent active TB disease from developing later. This medicine is often taken for three to four months and greatly lowers the risk of future illness.

Active TB treatment: Active TB disease is treated with several antibiotics taken together. Medicines are usually taken for six to nine months and must be taken exactly as directed. These medicines are usually oral tablets (taken by mouth). Common medicines may include:

• Isoniazid
• Rifampin
• Ethambutol
• Pyrazinamide

Drug-resistant tuberculosis: In some cases, TB does not respond to the usual medicines. This type of TB is harder to treat and may require different medicines for a longer time. These medicines may be given as shots or through an IV.

What are Possible Complications of Tuberculosis?

Without treatment, TB can cause serious health problems. Possible complications include lung damage, widespread infection throughout the body and infection of the brain, called TB meningitis.

What Is the Prognosis and Recovery for Tuberculosis?

Most children recover fully when TB is treated as directed. Cure rates are high when medicines are taken correctly and follow-up care continues.

Without treatment, TB can get worse over time. It can lead to severe illness or death and increases the risk of spreading infection to others.

How Can Tuberculosis Be Prevented?

Preventing TB focuses on early testing, treatment and protecting children who are at higher risk.

Doctors may also recommend TB screening for children in higher-risk groups, children who have been exposed to someone with TB, or for certain travel or healthcare-related reasons. Finding TB early helps prevent illness and reduces the risk of spread.

In some parts of the world where TB is common (Asia, Africa), a vaccine called the bacille Calmette-Guérin (BCG) vaccine is used. The BCG vaccine helps protect young children from severe forms of TB but does not fully prevent all TB infections.

Frequently Asked Questions About Tuberculosis

What is TB?

TB is a serious infection caused by the bacteria Mycobacterium tuberculosis. It mainly affects the lungs but can affect other organs like the brain, kidneys or spine.

Is tuberculosis contagious?

TB is only contagious in certain situations. A child with active TB disease in the lungs can spread TB through the air by coughing, sneezing or speaking. TB that is not active (called latent TB infection) cannot spread to others. Latent TB infection can reactivate and become active TB disease, so it is still important to treat latent TB infection. TB does not spread through touch, sharing food or touching surfaces.

What’s the difference between latent and active TB?

With latent TB infection, the TB bacteria are in the body but not active. Children do not feel sick and cannot spread TB. Active TB disease means the bacteria are active and causing illness. Children may have symptoms and need treatment right away. Both latent and active TB need to be treated as soon as possible.

Can TB be cured?

Yes. TB can be cured when treatment is taken exactly as prescribed. Most children recover fully when they take all their medicines and go to follow-up visits.

How long does TB treatment take?

For latent TB infection, medicine is often taken for three to four months. For active TB disease, medicines are usually taken for six to nine months. Some children may need to take medicine longer, especially if the TB is harder to treat.

Is TB still common in the United States?

TB is much less common in the United States than in many other parts of the world. But it still happens, especially in children who are in higher-risk groups or who have been exposed to someone with TB.