Tuberculosis (Mycobacterium tuberculosis)
Tuberculosis (TB) is a disease caused by bacteria that usually affect the lungs but can affect any part of the body, such as the kidneys, lymph nodes, bones, joints, brain, or spine. Not everyone infected with TB bacteria gets sick. People who don’t get sick are said to have “latent tuberculosis infection (LTBI),” and people who get sick have tuberculosis disease. Both conditions can be treated. Without treatment, LTBI can progress to TB disease. If not treated, TB disease can be fatal.
TB is spread through the air from one person to another when someone with TB disease of the lungs or throat coughs, speaks, laughs, or sings. People with TB disease are most likely to spread TB to people they spend every day with, such as family members, co-workers, schoolmates, and friends.
In New York, local health departments conduct contact investigations to minimize the spread of TB. They assign a case manager to every person with TB disease to assure coordination of care and treatment completion.
Tuberculosis Questions and Answers
What is tuberculosis?
Tuberculosis (TB) is caused by a bacterium (Mycobacterium tuberculosis complex). TB usually affects the lungs, but other parts of the body can also be affected, such as the lymph nodes, brain, spine, kidneys, bones, etc.
Not everyone infected with TB gets sick. As a result, there are two TB conditions: latent TB infection (LTBI), also called inactive TB, and active TB disease. TB disease can be prevented by treating latent TB infection. TB disease is usually treatable and curable.
Additional information: About Tuberculosis (cdc.gov)
What are the symptoms of TB Disease?
Only those with active TB disease have symptoms and are sick. Symptoms depend on where in the body the TB germs are growing. The most common part of the body to have disease is the lungs. Some common symptoms of TB disease include:
- Cough that lasts 3 weeks or longer
- Coughing up blood or phlegm (sputum)
- Chest pain
- Shortness of breath or difficulty breathing
- Fever and/or chills
- Sweating at night or night sweats
- Weight loss and/or loss of appetite
- Weakness and/or fatigue
- Other symptoms depend on the part of the body affected by TB
Additional information: Signs and Symptoms of Tuberculosis (cdc.gov)
How soon do symptoms of TB disease appear?
Many people infected with TB germs never develop TB disease. This is known as latent TB infection or inactive TB. If TB disease does develop, it can occur within weeks, months, or even years after infection. The risk of TB disease lessens as time passes. Treatment for latent TB infection can prevent the development of disease.
Additional information: Signs and Symptoms of Tuberculosis (cdc.gov)
What is the difference between latent tuberculosis infection and tuberculosis disease?
Latent tuberculosis infection (LTBI) means the person has the TB germs in the body but is not sick, has no symptoms or physical signs of disease, and cannot spread TB to others. Treating LTBI can prevent a person from getting sick and developing active TB disease.
Active TB disease is when TB germs become active (multiplying in the body). A person with active TB disease is usually sick and may be able to spread TB to others. Without treatment, active TB disease can be fatal.
Difference between Latent TB Infection and TB Disease
| Latent TB Infection | Active TB Disease |
|---|---|
| Has a small amount of TB germs in the body that are alive but inactive. | Has alive and active TB germs in the body. |
| No physical signs or symptoms and is not sick. | Usually feels sick and has physical signs/symptoms. Symptoms may include:
|
| TB blood test or TB skin test is usually positive. | TB blood test or TB skin test is usually positive. |
| Chest x-ray is normal. | May have abnormal chest x-ray. |
| Specimens are negative and do not show TB (e.g., negative smear and culture). | Specimens may be positive (e.g., positive smear and culture). |
| Can NOT spread TB to others. | May be able to spread TB to others. |
| Need treatment for latent TB infection to prevent disease. | Need treatment for TB disease. |
Additional information: About Inactive Tuberculosis (cdc.gov) and About Active Tuberculosis Disease (cdc.gov)
Who is at risk for TB?
Anyone can get TB, but you might have a higher risk for TB if you:
- Recently spent time with someone who had infectious active TB disease. You are at most risk of getting TB disease in the first two years after exposure. Children less than 5 years of age are at greater risk.
- Have a weaker immune system because of certain medications such as steroids and TNF inhibitors.
- Have health conditions such as diabetes, HIV, organ transplant, kidney disease, silicosis, or cancer.
- Engage in substance use (such as injection drugs or excessive alcohol).
- Were treated for active or latent tuberculosis but did not take your medications for the full treatment or were not treated correctly.
- Were born in, frequently traveled to, or stayed a long time in a country where TB is common. Additional information: TB Risk and People Born in or Who Travel to Places Where TB is Common (cdc.gov)
- Live or used to live in large group settings where TB is more common, such as homeless shelters, prisons, or jails.
- Work in places where TB is more likely to spread, such as hospitals, homeless shelters, correctional facilities, or nursing homes.
Additional information: Tuberculosis Risk Factors (cdc.gov)
How is tuberculosis spread?
Tuberculosis is spread through the air from person to person when someone with infectious TB disease of the lungs or throat coughs, sneezes, laughs, or sings. A person must be in close contact with someone with untreated infectious TB disease of the lungs or throat for a long period of time and needs to breathe in TB germs for infection to occur. People with active TB disease are most likely to spread TB germs to people they spend time with every day. TB is NOT spread by touching surfaces or sharing silverware, cups, toilet seats, etc.
How can I keep from spreading TB to others?
- Take all your TB medicine as directed.
- Do not go to work, school, religious gatherings, or social activities until your local health department says it is okay.
- Let healthcare providers know if you are still contagious when going to appointments.
- Wear a mask, if possible, around others such as healthcare providers and household members.
- Sleep or spend time in a separate room from other family/household members, if possible.
Additional information: Tuberculosis: Causes and How It Spreads (cdc.gov)
When and for how long is a person able to spread tuberculosis?
A person with active TB disease of the lungs or throat may be able to spread the TB germs to others until they have been on medicine for at least 5 days and possibly several weeks or more, depending on how severe the disease is. However, a person with latent TB infection, but not disease, cannot spread the infection to others, since there are no TB germs in the sputum (phlegm). The local health department will let the person with TB know when they can no longer spread tuberculosis to others.
Additional Information: Tuberculosis: Causes and How It Spreads (cdc.gov)
What are the tests for TB?
There are two types of tests for TB infection: the TB blood test and the TB skin test. Reasons for selection of test depend on test availability, reason for test, and cost.
The TB blood test (also known as the interferon gamma release assay or IGRA) requires a blood sample be drawn. The two TB blood tests available are the QuantiFERON-TB Gold Plus (QFT-Plus) and the T-SPOT. TB test (T-Spot). The TB blood test is not affected by the BCG vaccine. The TB blood test is the preferred test for most individuals.
The TB skin test requires a small amount of testing fluid (tuberculin or PPD) be injected into the skin in the lower arm. After 2 or 3 days you must return to have your skin test read. There may be induration (a firm bump) which is measured to determine if you are positive.
If you were exposed to TB recently, you may need to repeat your TB test 8-10 weeks after the last date of exposure. This test is the most important because it takes time for your body to test positive.
Additional information: Testing for Tuberculosis (cdc.gov)
What if I test positive for tuberculosis?
If you have a positive TB blood test or TB skin test, your healthcare provider will do other tests to see if you have TB disease or latent TB infection. These tests usually include a chest x-ray and may also include a test of the phlegm (sputum) you cough up. Because TB germs may be found somewhere other than your lungs, your healthcare provider may check your urine or do other tests. Occasionally, your provider might take tissue samples. If you have TB disease, you will need to take medicine to treat the disease. If you have latent TB infection (LTBI), it can progress to TB disease if you don't get treated. Treatment for LTBI usually requires fewer medicines for a shorter duration than treatment for TB disease.
What if I was vaccinated with Bacille Calmette-Guerin (BCG)?
BCG is a vaccine for TB that is not widely used in the United States. Many people born outside the U.S. received this vaccine as a small child or infant to prevent severe forms of the disease like TB meningitis. Unlike the TB skin test, the TB blood tests are not affected by prior BCG vaccination and are the preferred test.
Additional information: Tuberculosis Vaccine (cdc.gov)
What is the treatment for tuberculosis?
Both latent TB infection and TB disease can be treated. It is important to finish all TB medicines as directed by your healthcare provider.
The treatment for latent TB infection usually includes one or two medications for one, three, four, six, or nine months, depending on your treatment plan.
People with TB disease need several medications for four to six months or more. Initial medications usually include three or four anti-TB drugs, and medications may be altered based on laboratory test results. The exact medication plan must be determined by a health care provider. Directly observed therapy (DOT) programs are recommended for all persons with TB disease to help them complete their treatment.
Additional information: Treating Tuberculosis (cdc.gov)
What is directly observed therapy (DOT)?
DOT is when a person with TB disease or latent TB infection meets with a health care worker every day or several times per week. You will meet at a place you both agree (e.g., home, clinic) or electronically through a video-capable device such as a smartphone. Medicines are taken while the health care worker watches. DOT is used to remind patients to take their medication, look for any side effects, and assure medications are working as they should.
What is drug-resistant or multidrug-resistant tuberculosis?
Drug-resistant TB is when TB germs are resistant to the medicine normally used to treat TB disease. This means the medicines no longer kill the TB germs. Multidrug-resistant TB (MDR-TB) is caused by TB germs that are resistant to at least two of the most important TB medicines: isoniazid and rifampin. Extensively drug-resistant TB (XDR-TB) is a subset of MDR-TB in which the strains of TB bacteria are resistant to nearly all medicines used to treat TB disease. These strains are very difficult to treat.
Drug-resistant TB can still be treated with special medicines. Treatment sometimes takes longer and may have more side effects. People with drug-resistant TB should see an expert who can closely observe their treatment to make sure it is working. Directly observed therapy is recommended for all patients with drug-resistant TB.
Additional information: About Drug-Resistant Tuberculosis Disease and Treating Drug-Resistant Tuberculosis Disease (cdc.gov)
Who is at risk for drug-resistant TB?
People are at risk for drug-resistant TB if they:
- Have spent time with someone with drug-resistant TB. People can spread drug resistant TB to others.
- Do not take all their TB medicines as directed.
- Develop TB disease again after having taken TB medicines in the past.
- Come from or spent time in areas where drug-resistant TB is common.
Additional Information: About Drug-Resistant Tuberculosis Disease (cdc.gov)
I have TB, how can I connect with other TB survivors?
We are TB, and Somos TB (for Spanish-speakers), is a community of TB survivors, people being treated for TB, and their family members, committed to the common goal of eliminating TB. The group provides comprehensive peer support for current TB patients and TB clinics.
