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What is tuberculosis?

Tuberculosis (TB) is a serious disease caused by the germ Mycobacterium tuberculosis and/or Mycobacterium bovis. Mycobacterium tuberculosis causes most TB in humans. Mycobacterium bovis is part of the tuberculosis family, primarily a disease of cattle but may affect other animals as well as humans. TB can hurt a person's lungs or other parts of the body. However, TB can be prevented with treatment and it can be cured.

How are TB germs spread?

TB is spread when a person who has active, untreated TB germs in their lungs or throat coughs, sneezes, laughs, or speaks, spreading their germs into the air. A person who breathes in TB germs usually has had very close, day-to-day contact with someone who has active TB disease. That's why a person usually gets TB germs from someone he/she spends a lot of time with, like a family member, friend, or close co-worker who has the disease.

TB germs can also be transmitted through eating or drinking contaminated, unpasteurized (raw) milk products produced in areas where Mycobacterium bovis is present in cattle. A person is not likely to get TB from someone coughing in the subway or at a restaurant. TB is not spread by sitting on a toilet seat or by sharing dishes, utensils, sheets, clothing or other inanimate objects.

What happens when someone breathes in TB germs?

When you first breathe in TB germs into your lungs, your body protects you by building a wall around the germs the way a scab forms over a cut. This makes the germs go to "sleep" and stops them from hurting your body. Sleeping TB germs are called "latent TB". A person with latent TB are said to have latent TB infection (LTBI). Latent TB germs can stay asleep for a long time, sometimes for life. However, sometimes TB germs "wake up" when body defenses are weakened. When this happens, you have active TB disease.

What are the tests for TB?

  1. The tuberculin skin test (TST), also called Mantoux skin test, shows if a person has been infected.
  2. QuantiFERON- TB test is a blood based test for diagnosing latent tuberculosis (TB) infection (LTBI). However, it is not useful yet for many people and is not used frequently.
  3. A chest x-ray is given if the Mantoux skin test shows that a person has been infected. The x-ray shows if any damage has been done to the lungs.
  4. A sputum test shows if there are TB germs in a person's lungs. Sputum is phlegm from deep inside the lungs.

Who should get tested for TB?

  • A person who has symptoms of active TB disease
  • A person who has been exposed to someone (a family member, friend, or co-worker) who has active TB disease
  • A person who has HIV infection or certain medical illnesses such as diabetes or chronic kidney failure
  • A person who is taking steroid or other immune suppressing drugs for chronic medical conditions
  • A person who lives or works in a homeless shelter, prison, hospital, nursing home or other similar group setting
  • A person who has recently come to the U.S. from a region with a lot of active TB such as Africa, Asia, the Caribbean, Eastern Europe, and Latin America
  • A student entering the New York City school system for the first time at the secondary school level (intermediate, junior, or middle schools, and high schools)

What do I do if I have been exposed to someone with active TB?

If you have been exposed to someone with active TB disease or meet any of the criteria for testing listed in the previous question, you should get a TB skin test. The TB skin test is an easy way to tell if the TB germs are in your body. A trained health care worker will examine your arm 2 or 3 days after the test has been placed. If the test is "positive," it can mean the person is infected with TB bacterial. Additional testing such as a chest x-ray and a medical examination are needed to determine if the person has LTBI or TB disease. 

What if my first TB skin test doesn't show anything?

Most likely, you do not have TB infection. However, someone with active TB may not show a reaction to the TB skin test. If you have symptoms that are consistent with active TB, you may still need evaluation. If you were exposed to TB recently, you may have a false-negative result to the skin test if the test was done in less than 8 weeks after you were last exposed.

You may need another skin test in 8 weeks after your exposure to TB to make sure the skin test is not positive, since it can take that long for the test to become positive. This is what we call the "window period." During the window period between the two skin tests, you can be given treatment for latent TB infection, even if the result of your skin test is negative.

If you were exposed to TB in the past, your ability to react to a skin test diminishes over time. Therefore, you may need to undergo two-step testing the first time that you are tested. With this type of testing, an initial skin test is done; if the result is negative, a second skin test is given 1 to 3 weeks later. Talk to your health care worker for more information.

I have been exposed to someone with TB but do not have a positive skin test; do I still need to take medicine?

If you have been exposed to someone who has active TB, and the result of your skin test is "negative," you most likely do not have TB germs in your body. You probably do not need to take medicine. However, in some instances your doctor may recommend treatment, even if the result of your skin test is negative. Also, someone whose immune system is weakened by chronic medical conditions may also be recommended to take medicine even though the TB skin test may not be positive.

Do I need the TB skin test even if I was vaccinated with BCG?

Yes. The BCG vaccine usually does not protect people against TB. Even if you had the vaccine, you can still become infected with the TB germ and develop active TB disease. Therefore, you may still need a TB skin test. Talk to your health care worker for more information.

Do I need a chest x-ray every year?

No. If the first chest x-ray is negative for active TB disease, a chest x-ray does not need to be repeated every year for a person with a positive TST result who is not showing symptoms of active TB disease. Some employers may still recommend a follow-up chest x-ray routinely but this is not indicated, or recommended by city, state, or federal health agencies. You should ask your employer to contact us.

What does it mean to have latent TB infection (LTBI)?

Latent TB infection means that TB germs are in a person's body but are not active. Many healthy people have LTBI. Most of them never get sick. The germs are in their bodies, but are not active and cannot be spread to others.

Can I spend time with family and friends if I have latent TB infection?

Yes. If you have latent TB, you cannot spread TB to other people. You can work and go to school and do your normal routine. You cannot spread TB to others.

What is the treatment for latent TB infection (LTBI)?

There are several medicines for latent TB infection. If you have LTBI, your doctor will decide which one is best for you. Treatment for LTBI generally lasts for 9 months, however there are also short-course regimens now that last 3 to 4 months. It is important that you finish the treatment.

The most common drug used for the treatment of LTBI is a medicine called isoniazid, or INH. Most people can take INH without problems. Make sure that you tell your health care worker about any health problems that you have or any medicines that you are taking. Children and adults who can't swallow pills can get INH in liquid form.

How long do I have to take INH?

You must take INH pills for at least 3 months to kill the TB germs. You might think that it's hard to take pills for a long period of time, especially when you don't feel sick. But it's important to keep taking your medicine. If you stop taking the pills too soon, some germs may survive and you can still be in danger of getting TB disease.

Is INH safe?

Most people who take it have no side effects. However, tell your doctor or nurse right away if you see any changes in your health or appearance while taking the medicine. While you take INH, you can continue to work, go to school, and participate in regular activities.

What are some changes that I should watch out for when taking INH?

  • Yellowish skin or eyes
  • Loss of appetite
  • Stomach cramps or pain
  • Vomiting
  • Nausea
  • Dark urine
  • Changes in eyesight
  • Unexplained fatigue

When should I take an INH?

It is easier to remember to take your pill if you take them at the same time every night.

Here are some other suggestions:

  • Eat healthy food and get enough rest.
  • AVOID alcoholic beverages.
  • Tell your doctor or nurse about any other medications you are taking and before beginning any new ones. Do not take Tylenolacetaminophen, or other over-the-counter medicines without consulting your doctor first.

What happens if I forget to take my INH pill?

If you forget to take your pill one day, do not take two the next day. Do not worry; just continue taking your daily dose the next day as prescribed. But if you forget too many times, the medicine may not work any more. Always tell your health care worker if you forget to take your pill.

It is especially important that people who have HIV infection DO NOT miss taking their medication.

What is directly observed therapy for latent TB infection (LTBI)?

Directly observed therapy for latent TB infection means that a health care worker observes a patient take his/her medications. It is a way of ensuring that the patient remembers to take his/her medication as prescribed. It usually works like this: a health care worker meets with the patient every time a dose of medication is scheduled and observes that the medication is swallowed. The health care worker and the patient decide together where to meet -- at home, at work, or at some other location. Directly observed therapy for LTBI is the best way to make sure that TB is prevented and cured.

Why do I need regular check-ups?

You will be given regular (at least monthly) appointments to see the doctor or nurse for the entire time you are taking your medication. These visits are not just for picking up your medication . The health care worker wants to see you to:

  • Make sure you're not having any side effects from the medication
  • Give you your prescribed medication
  • Answer any questions you may have about your treatment

I feel fine. Do I really need to take medicine for latent TB infection?

You feel fine now because the TB germs are not active. Your body's defenses have built a wall around the germs the way a scab forms over a cut. As long as the TB germs are not active, they can't hurt you and cannot be spread to others. But you need medication to prevent the inactive germs from becoming active.

Although TB germs are not active, they are still alive. Later, maybe many years later, they can become active, break out of the walls, multiply, and damage your lungs and other body organs.

By taking medicine now, you greatly reduce the risk that the germs will become active, and therefore reduce the risk that they will hurt you or anyone else. Persons who have HIV infection especially need medicine to prevent TB. Their bodies' defenses are not strong enough to fight the germs without help.

What is meant by active TB disease?

Active tuberculosis disease is a serious illness caused by active TB germs. It is possible to get active TB disease shortly after the germs enter the body. It is also possible, even after many years, for inactive TB germs to become active when body defenses are weakened. This may be the result of aging, a serious illness, drug or alcohol abuse, or HIV infection. When defenses are weakened and inactive TB germs become active, the germs can then break out of the walls, begin multiplying, and hurt the lungs or other organs. A person with active TB disease may feel sick and usually can spread TB to others.

What are the signs and symptoms of active TB disease?

TB can attack any part of the body, but the lungs are the most common target. A person with active tuberculosis disease may have some or all of the following symptoms:

  • A cough that last for 3 weeks or more
  • Fever or chills
  • Night sweats
  • Loss of appetite
  • Weight loss
  • Constant tiredness
  • Coughing up blood (occasionally)

Can active TB disease really be cured?

Yes. Active TB disease can be cured with medicine. If you have active TB, you must take your medicine for at least 6 months. TB treatment is free to the patient at the Department of Health & Mental Hygiene chest centers.

Can a patient with active TB disease infect other people?

Usually, after a week or more of taking effective medication, most patients with active TB disease will stop spreading germs. A doctor will test the patient and then decide when the patient is no longer contagious. Most TB patients live at home and can continue their normal activities as long as they are taking the TB medicine.

Why do I need to take TB medicine for a long time?

The only way to cure active TB is take all of your medicine for at least six months. Be patient. TB germs take a long time to die. Even if you feel better after a few weeks, continue taking your medicine. If you do not, you will stop feeling better. You may even get sicker.

When can I be discharged from the hospital?

You can be discharged when you

  • Have had improvement in your symptoms, i.e., fever and coughing
  • Are able to tolerate anti-TB medications
  • Agree to participate in directly observed therapy (DOT) and this has been arranged for you with an employee of the Department of Health & Mental Hygiene, Bureau of TB Control
  • Are willing to follow up with outpatient care and have necessary tests done

In addition you must show that you

  • Live alone, or are going back to a living environment where the other members of the household are healthy and wish to have the you home,
  • Are willing to cover your mouth when coughing,
  • Will not receive visitors at home or visit others
  • Will not have significant contact with persons who have weak immune systems, i.e., cancer or HIV
  • Will not live with or care for infants, young children < 5 years old, unless the children have been evaluated for TB infection and are taking anti-TB medicines.

The Bureau of TB Control must be able to

  • Check that you have a stable address
  • Make a home visit, if necessary

Your doctor will let you know when you can have visitors or leave your house.

When can I go to school or work?

You can return to school or work if

  • You have started anti-TB medicines and are not having any bad side effects from them
  • You are feeling better
  • You are not likely to transmit TB to others in the work or school environment
  • Your doctor has decided it is safe for you to go back because you are no longer infectious or work in a place where you are not exposing people who are sick

Staff or students returning to a school after being infectious with TB disease must obtain a certificate of recovery from the Health Department before being permitted to return. Staff or students
returning to a school for children five years and under after being infectious with TB disease must obtain a written statement of recovery from a healthcare provider before being permitted to return. In the case of returning children, the statement of recovery must state that the child is no longer infectious and that the period of isolation or exclusion pursuant to NYC Health Code Article 11 has ended.

What happens if I don't take my medicine?

If people with active TB disease do no take their medication, they can become seriously ill, they can develop germs that are resistant to the TB medications and may even die. But people with active TB disease can be cured, if they have proper medical treatment and take their medication as prescribed.

What is drug-resistant TB?

There are times when TB germs are "resistant" to one or more of the TB medicines most often prescribed by doctors. This means that the medicines are not able to kill the TB germs. Drug-resistant TB can develop if people with active TB take their medicine incorrectly, or if they have not been given the right TB medicines. When this happens, combinations of other TB medicines have to be given to the patient. These medicines are not as effective and have to be taken much longer.

A person with untreated drug-resistant TB of the lungs or throat can spread drug-resistant germs to other people. Drug-resistant TB can take much longer to cure than regular TB.

How can people fight TB?

Testing for TB should be done when there has been contact with someone who has active TB disease. (See "Who should get tested for TB?").

The best way to fight TB is to make sure that a person who needs medicine takes it regularly. This includes:

  • A person who is sick with active TB disease. This person has active germs and can infect others. The ONLY way a person with active TB disease can get well is by taking his/her medicine as directed.
  • A person who is infected but is not yet sick. This person has inactive germs that are sleeping. This person may not be sick now, but the TB germs can become active later on in life and make him/her sick. Taking medicine for treatment of latent TB infection for several months, as prescribed by the doctor, is the best way to get rid of TB germs and prevent illness. However, in some instances, medicine for treatment of latent TB infection may not be prescribed to a person because of certain medical conditions or other factors.
  • A person who is a close contact to someone with active TB disease, regardless of age. This person should take medicine to prevent TB as directed by the doctor.

Can the health department help me if I have TB?

The New York City Department of Health & Mental Hygiene chest centers offer TB tests, medicines, and check-ups FREE of charge to the patient. You do not need health insurance and you do not need to worry about immigration. No one will ask about your status. Your health is our primary concern. Our chest centers provide high quality care. Our staff speak many languages. We can answer your questions about TB. We can prevent and cure TB.

What to do if there is a reported case of active TB in my school?

  • NYC Dept of Health must be notified by the physician within 24 hours. This is a reportable disease.
  • There is a standardized protocol that the DOH must follow as part of the investigation for the source case and other potential contacts.
  • DOH will notify the UFT that there is a confirmed case.
  • When there is a confirmed case, DOH provides a letter to staff and parents with information regarding how the DOH will proceed.
  • The DOH will visit the school, meet with the principal and discuss the process of their investigation. They are always willing to present the information in an educational session during the day for staff and in the evening for parents.
  • The DOH may also conduct tuberculin skin testing (TST) at the school. This test shows if a person has been infected with TB germs. This test is generally after 8 weeks after exposure to someone with active TB because it can take several weeks after infection for your immune system to react to the TB skin test. If you were exposed to TB recently, you may have a false-negative result to the skin test if the skin test was done in less than 8 weeks after you were last exposed. The DOH will administer the test at the school and return to the school 2-3 days later to “read” the skin test.
  • If you have a positive reaction to the skin test, the DOH may do other tests to see if you have active TB disease. These tests may include a chest X-ray, medical examination and a test of the phlegm you cough up.

What happens if there is a suspected case of TB in my school?

  • The UFT Health and Safety Department will contact the TB unit of the DOH directly and discuss all the information we have about the student or staff member. (Name, DOB, hospital they’ve been treated in)
  • At no time will the confidentiality of the student or staff member be violated.

To find out more about tuberculosis, call 311.