Health Topics

Tuberculosis

Tuberculosis (TB) is caused by bacterium (germ) called mycobacterium tuberculosis. TB most often affects the lungs but it can also affect other parts of the body, such as the brain, kidneys or spine. People who have TB disease in the lungs spread TB germs through the air when they cough, laugh, sneeze, talk or sing. 

  • You may get a TB infection if the TB germ enters your body. This TB infection will stay inactive (asleep) as long as your body can fight the infection and stop the germs from growing.
  • When your body can no longer fight the infection the TB germs will grow and spread causing TB disease.
  • It usually takes close, long-lasting and/or frequent contact with someone who is sick with TB disease to become infected. For some people TB disease can happen within weeks of breathing in the TB germ. Other people may get sick years later.
  • A TB Skin Test or IGRA (Interferon Gamma Release Assay blood test) can let you know if you have a TB infection.
  • Watch TB personal stories

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TB Infection


  • People with TB Infection (TBI) have TB bacteria in their bodies, but they are not sick, have no symptoms and can’t give TB to others because the bacteria are not growing (multiplying). TB bacteria will stay inactive as long as the body can fight them and stop them from growing.
  • If the body stops fighting the TB bacteria, they will wake up (activate) and start to grow. When the germs grow and spread, it is called TB disease. People with TB disease can get very sick and can spread TB bacteria to other people.
  • About 5 to 10% of people with TBI develop TB disease.
  • TBI is easy and free to treat. Taking medicine for TBI prevents your TB from growing and causing TB disease.

TB Disease


  • If your body can’t fight the TB germs they can start to grow and spread in your body. When this happens, it is called TB disease; it can happen to anyone with TBI at any time.
  • If you are sick with TB disease, you can spread the germs to others.
  • If you do get sick with TB disease you may have some or all of these symptoms:
    • Cough for more than two (2) weeks Chest pain when you cough or breathe
    • Coughing up blood or sputum (phlegm)
    • Feeling weak and tired
    • Weight loss
    • Loss of appetite
    • Sweating at night
    • Fever, chills greater than
A Person with TB Infection A Person with TB Disease
  • Has no symptoms
  • May have some or all of these symptoms:
    • Cough for more than two (2) weeks
  • Chest pain when coughing or breathing
  • Coughing up blood or sputum (phlegm)
  • Feeling weak and tired
  • Weight loss
  • Loss of appetite
  • Sweating at night
  • Fever, chills
  • Does not feel sick
  • Usually feels sick
  • Cannot spread TB germs to others
  • May spread TB germs to others
  • Usually has a skin test or blood test showing TB infection
  • Usually has a skin test or blood test showing TB infection
  • Has a normal chest x-ray and a negative sputum smear
  • May have an abnormal chest x-ray, or positive sputum smear or culture
  • Needs treatment for 4 to 9 months with medicine to prevent TB disease
    • Medicine  kills the TB germs in your body before they have a chance to grow and make you sick.
    • Public Health provides these medicines for free
    • After finishing treatment, the risk of developing TB disease is about less than 1%.
  • Needs treatment with antibiotics for TB disease for six months or more.
    • TB disease can be cured; but TB germs are very strong and hard to get rid of.
    • Public Health provides treatment for TB disease for free.  

A TB Skin Test can tell if you have TB germs in your body. This test cannot tell how long you have had the germs or if the TB germs are growing (TB disease). If you cannot have a TB Skin Test, your doctor may order a blood test (Interferon Gamma Release Assay - IGRA).

Steps for a TB Skin Test:

  1. A doctor or nurse injects a small amount of fluid, called tuberculin, just under the skin of your forearm. 
  2. You can go home. Do not touch or cover the spot where you had the injection, even if it’s red or itchy.  
  3. Return to the clinic 48 to 72 hours after you had your TB Skin Test.  A doctor or nurse will measure the area. The TB Skin Test is usually positive if swelling the size of a dime or bigger develops at the area. A positive test does not mean you are sick with TB disease.

Public Health Services provides free TB Skin Test only for people who have been named as a contact with a person who has TB disease. 

TB Skin Test are available at:

TB Skin Tests are covered under the Ontario Health Insurance Plan (OHIP) for:

  • People who are named as a contact of a TB case.
  • People who need a TB Skin Test for medical reasons
  • People who have recently immigrated from countries where TB is more common.
  • People who require  a  TB Skin Test for admission  to a daycare, pre-school program or a school, community college, university or other educational institution or program (including a work placement that the program may require)
  • People who are 65 years of age or younger and need to be admitted to a Long Term Care Facility
  • TB skin tests are not free when needed for employment or volunteer purposes.

IGRA (Interferon Gamma Release Assay) is a blood test that can be used to see if a person has the TB germ in their body. IGRA is not free under the Ontario Health Insurance Plan (OHIP).

  • A positive skin test or IGRA shows you have TB infection. More tests will be needed to make sure the TB germ is not growing. This usually includes a check-up for signs and symptoms of TB disease and a chest x-ray
  • If you have symptoms of TB disease or if your chest x-ray shows you may have TB disease, your doctor may recommend a sputum test to see if there are germs in your lungs or throat.
  • Once your doctor tells you that you do not have TB disease, ask about medicine to prevent getting TB disease in the future. This medicine is free from Public Health.

TB Facts

What is Directly Observed Therapy (DOT)?
DOT stands for directly observed therapy. During DOT a Public Health Nurse (PHN) will visit you virtually or in person at home to watch you take your Tuberculosis (TB) medicine. They will visit you three to five times per week when you first start your medicine. The PHN will encourage and support you until your treatment is finished.

How does the PHN help?
While you are taking your medicine, the PHN will:

  • Deliver your medicine to you free of charge.
  • Check for side effects
  • Remind you of your doctor appointments
  • Help you remember to take your TB medicine.
  • Give you and your family the chance to ask questions.

Why is it important to take your TB medicine every day?

  • Taking your TB medicine every day will cure your TB.
  • If you don’t take your TB medicine every day, the TB germs can grow back and may become harder to cure.
  • It is very important to take your TB medicine even when you feel better because it takes a long time to kill every TB germ.

Tuberculosis (TB) Disease

  • Tuberculosis (TB) is a disease caused by germs (bacteria) that are spread from person to person through the air. TB bacteria are put into the air when a person with TB disease of the lungs or throat coughs, sneezes, speaks or sings. TB is not spread by sharing utensils, plates, cups, clothing, bed linen, furniture, toilets or by shaking hands.

How do I isolate?

  • Stay at home and away from people.
  • Do not go to work, school, or any other public places.
  • Do not ride on buses, subways, trains, or airplanes.

How do I protect my family?

  • Tell your Public health Nurse right away if you live with babies, young children and people with weak immune systems.
  • Sleep alone in a separate room.
  • Open the curtains and windows in your house. A breeze and sunlight may help get rid of TB germs in the air.
  • Wear a mask when you are around people in your home.
  • Cover your mouth and nose with a tissue when you cough or sneeze or use your upper sleeve. Do not cough or sneeze into your hands. Put the used tissues in the garbage and wash your hands.

How do I protect other people?

  • Stay at home and do not have visitors or friends to your home.
  • Always wear a mask when you go to doctor’s appointments, blood tests or x-rays.
  • You can go out for short walks around your neighborhood without wearing a mask. Do not walk with other people. Do not stop and talk with other people.
  • If you need to go to the emergency room by ambulance, wear a mask. Tell the 911 operator, paramedics and hospital staff that you have TB.

How long will I need to be in home isolation?

  • The amount of time you will be in isolation will depend on how well your body fights off the TB germs. Your doctor will collect sputum tests. The sputum test will tell your doctor if the medicine is working to kill the TB germs.
  • Taking every dose of your TB medicine will kill the TB.
  • Your doctor or Public Health Nurse will tell you when you can come out of isolation.

What is sputum?

  • Sputum is a thick white or yellow coloured mucus that comes from the lungs.  Sputum is not saliva (spit). Saliva comes from your mouth. It is thin, clear and watery. Do not collect saliva for this test.

Why should I do a sputum test?

  • Your doctor is ordering this test to see if TB germs are in your lungs.  If you are taking medicine for TB, the sputum test will tell your doctor if the medicine is working to kill the TB germs.

How do I collect sputum?

You will be given three plastic bottles for collecting sputum. You will also be given three lab bags with lab forms.

Do this every morning for 3 days. Use a different plastic bottle each day. Start with bottle #1 and end with bottle #3.

  • Upon waking, do not eat or drink, brush your teeth, smoke or use mouthwash. You may want to take a hot shower before collecting sputum; it will make it easier for you to cough up sputum.
  • Remove the plastic bottle from the plastic lab bag. Do not remove the lab form from the bag. Open the plastic bottle. Do not touch the inside of the bottle.
  • Breathe in deeply 2 to 3 times and then cough deeply from the chest to bring up sputum from the lungs. Thick sputum collects in the lungs overnight. Try to cough up at least 1 to 2 teaspoons.
  • Spit the sputum into the plastic bottle. Close the plastic bottle cap tightly.
  • Place the bottle into the lab bag and close it.
  • Put the plastic lab bag with the sputum bottle in the fridge right away to keep it cold. Do not freeze.
  • Wash your hands.

TB Medicine

Tips for taking your TB medicine:

  • Take your medicine at the same time each day.
  • Use an alarm on your cell phone or clock to remind you to take your medicine.
  • Use a weekly pill container (dosette) or use a calendar to mark off each day you take your pills.
  • Keep all appointments with your doctor and go for your blood tests as scheduled.
  • Keep all medicine away from children. Put it in a cool, dry place (not in the bathroom) away from sunlight.

What is Isoniazid?

  • Isoniazid is a medicine (antibiotic) that is used to get rid of the germ (bacteria) that causes Tuberculosis (TB).
  • The TB germ is very strong and hard to get rid of. You will need to take this medicine every day for many weeks to get rid of TB.

Taking Isoniazid:

  • You should tell your doctor:
  • About all medicines you are taking, including vitamins.
  • If you are breastfeeding, pregnant or planning to get pregnant.

How do I take this medicine?

  • Take the medicine at the same time every day.
  • If you miss a dose, take it as soon as you remember but never take two doses at one time.
  • Take the medicine on an empty stomach (one hour before or 2 hours after a meal), and with a full glass of water. If you get stomach pain, you can take this medicine with food.
  • Do not drink alcohol while taking this medicine. You could harm your liver.
  • Do not stop this medicine without speaking to your doctor or a Public Health Nurse.

What side effects can I get?

  • Most people have no problems while taking this medicine
  • Some people get side effects when they first start the medicine. These side effects are very common and go away as your body gets used to the medicine. You may get:
    • Skin rash or itchiness
    • Loss of appetite
  • Some people can get serious side effects from this medicine. These side effects are rare but can cause serious harm. Call your doctor right away if you get:
    • Nausea or vomiting for 3 days or more
    • Stomach cramps or pain
    • Painful or tingling feeling in fingers or toes
    • Headache or dizziness
    • Yellowing of skin or whites of the eyes
    • Very dark (tea-colored) urine
    • Fever or chills for 3 days or more
    • Fatigue or feeling very tired
    • Joint or muscle pain

Why do I need to take Pyridoxine? (Vitamin B6)

  • Tingling and numbness of the fingers and toes is a possible side effect of Isoniazid. Taking Vitamin B6 may help prevent this side effect.

What is Pyridoxine?

  • Pyridoxine is a medicine (vitamin B6) your body needs to help you use the energy from the food you eat. It is needed to make red blood cells and helps the nerves in the body work properly.
  • Some medicines used to treat TB can cause low Vitamin B6 in the body. 
  • Pyridoxine helps to prevent and treat low Vitamin B6 in the body.
  • Vitamin B6 is found in many foods such as chicken, fish, chick peas and bananas.

Taking Pyridoxine:

  • Before starting this medicine, you should tell your doctor:
  • About all medicines you are taking, including vitamins.
  • If you are breastfeeding, pregnant or planning to get pregnant.

How do I take this medicine?

  • Take the medicine at the same time every day.
  • If you miss a dose, take it as soon as you remember but never take two doses at one time.

What side effects can I get?

  • Most people have no problems while taking this medicine.
  • Other TB medicine can cause side effects. It is important to know what side effects to watch for with your other TB medicine.
  • Call your doctor if you have questions or concerns about side effects.

What is Rifampin?

  • Rifampin is a medicine (antibiotic) that is used to get rid of the germ (bacteria) that causes Tuberculosis (TB).
  • The TB germ is very strong and hard to get rid of. You will need to take this medicine every day for many weeks to get rid of TB.

Taking Rifampin:

  • You should tell your doctor:
  • About all medicines you are taking, including vitamins.
  • If you are breastfeeding, pregnant or planning to get pregnant.
  • If you are taking birth control pills. Birth control pills may not work while taking RMP.

How do I take this medicine?

  • Take the medicine at the same time every day.
  • If you miss a dose, take it as soon as you remember but never take two doses at one time.
  • Take the medicine on an empty stomach (one hour before or 2 hours after a meal), and with a full glass of water. If you get stomach pain, you can take this medicine with food.
  • Do not drink alcohol while taking this medicine. You could harm your liver.
  • Do not stop this medicine without speaking to your doctor or a Public Health Nurse.

What side effects can I get?

  • Most people have no problems while taking this medicine
  • Some people get side effects when they first start the medicine. These side effects are very common and go away as your body gets used to the medicine. You may get:
    • Skin rash or itchiness
    • Drowsiness or mild dizziness
    • Headache
    • A red-brown colour in your saliva, tears, urine and stool. This is not harmful, but it will stain your soft contact lenses or clothing.
  • Some people can get serious side effects from this medicine. These side effects are rare but can cause serious harm. Call your doctor right away if you get:
    • Nausea or vomiting for 3 days or more
    • Stomach cramps or pain
    • Fatigue or feeling very tired
    • Very dark (tea-colored) urine
    • Yellowing of skin or whites of the eyes
    • Fever or chills for 3 days or more
    • Confusion or unusual behaviour
    • Blurred vision

What is Pyrazinamide?

  • Pyrazinamide is a medicine (antibiotic) that is used to get rid of the germ (bacteria) that causes Tuberculosis (TB).
  • The TB bacteria is very strong and hard to get rid of. You will need to take this medicine every day for many weeks to get rid of TB.

Taking Pyrazinamide:

  • You should tell your doctor:
  • About all medicines you are taking, including vitamins.
  • If you have had kidney or liver disease, gout or diabetes.
  • If you are breastfeeding, pregnant or planning to get pregnant.

How do I take this medicine?

  • Take the medicine at the same time every day.
  • If you miss a dose, take it as soon as you remember but never take two doses at one time.
  • Take the medicine on an empty stomach (one hour before or 2 hours after a meal), and with a full glass of water. If you get stomach pain, you can take this medicine with food.
  • Do not drink alcohol while taking this medicine. You could harm your liver.
  • Do not stop this medicine without speaking to your doctor or a Public Health Nurse.

What side effects can I get?

  • Most people have no problems while taking this medicine
    • Some people get side effects when they first start the medicine. These side effects are very common and go away as your body gets used to the medicine. You may get:
    • Skin rash or itchiness
    • Loss of appetite
  • Some people can get serious side effects from this medicine. These side effects are rare but can cause serious harm. Call your doctor right away if you get:
    • Nausea or vomiting for 3 days or more
    • Pain and swelling in the joints
    • Fatigue or feeling very tired
    • Very dark (tea-colored) urine
    • Yellowing of skin or whites of the eyes
    • Fever or chills
    • Unusual bleeding or bruising
    • Difficulty with urination

This medicine may make your skin sensitive to sunlight. Avoid long exposure to sunlight. Wear protective clothing, sunglasses, and sunscreen when in the sun.

What is Ethambutol?

  • Ethambutol is a medicine (antibiotic) that is used to get rid of the germ (bacteria) that causes Tuberculosis (TB).
  • The TB germ is very strong and hard to get rid of. You will need to take this medicine every day for many weeks to get rid of TB.

Taking Ethambutol:

  • You should tell your doctor:
  • About all medicines you are taking, including vitamins.
  • If you have had kidney or liver disease, gout or eye problems.
  • If you are breastfeeding, pregnant or planning to get pregnant.

How do I take this medicine?

  • Take the medicine at the same time every day.
  • If you miss a dose, take it as soon as you remember but never take two doses at one time.
  • Take the medicine on an empty stomach (one hour before or 2 hours after a meal), and with a full glass of water. If you get stomach pain, you can take this medicine with food.
  • Do not drink alcohol while taking this medicine. You could harm your liver.
  • Do not stop this medicine without speaking to your doctor or a Public Health Nurse.

What side effects can I get?

  • Most people have no problems while taking this medicine
  • Some people get side effects when they first start the medicine. These side effects are very common and go away as your body gets used to the medicine. You may get:
    • Skin rash or itchiness
    • Loss of appetite
    • Nausea or upset stomach
  • Some people can get serious side effects from this medicine. These side effects are rare but can cause serious harm. Call your doctor right away if you get:
    • Blurred vision or changes in your vision
    • Eye pain
    • Not able to see the colors red and green
    • Nausea, vomiting or diarrhea for 3 or more days
    • Stomach cramps or pain that do not go away
    • Very dark (tea-colored) urine
    • Yellowing of skin or whites of the eyes
    • Painful or tingling feeling in hands and feet