Questions and Answers 

About Tuberculosis

2014

Q&A About TB |i 

Questions and Answers 


About Tuberculosis
 

2014 

Questions and Answers About Tuberculosis ( TB) was written to provide information on the 

diagnosis and treatment of TB infection and TB disease for persons who do not have a medical 

background. Key audiences for this booklet are persons with or at risk for TB; persons who 

provide services for those at high risk for TB such as correctional officers, homeless shelter 

workers, emergency responders; persons who may have been exposed to someone with TB 

in a workplace or school setting; and persons who want to learn more about this disease. For 

additional information on TB, please visit the CDC website: http://www.cdc.gov/tb/ 

U.S. DEPARTMENT OF HEALTH AND HUMAN SERVICES
 

Centers for Disease Control and Prevention
 

National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention
 

Division of Tuberculosis Elimination 

ii | Q&A About TB 
Q&A About TB |iii 

 

 

 

 

 

 

 

CONTENTS

For definitions of common terms related to TB, see the glossary at the back of this booklet (page 18).

INTRODUCTION


What is TB? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
 

Why is TB still a problem in the United States? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
 

How is TB spread? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
 

What is latent TB infection? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
 

What is TB disease? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
 

TESTING & TREATMENT 

Should I get tested for TB? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
 

What are the tests for TB infection? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
 

What if I have a positive test for TB infection? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
 

What if I have been vaccinated with BCG? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
 

If I have latent TB infection, how can I keep from developing TB disease? . . . . . . . 8
 

What if I have HIV infection? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
 

If I was exposed to someone with TB disease, can I give TB to others? . . . . . . . . . 10
 

TB DISEASE
 

How is TB disease treated? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
 

What are the side effects of TB disease medicines? . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
 

Why do I need to take TB medicines regularly? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
 

What is directly observed therapy (DOT)? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
 

How can I remember to take my TB medicines if I am not on DOT? . . . . . . 15
 

How can I keep from spreading TB? . . . . . . . . . . . . . . . . . . . . . 15
 

What are multidrug-resistant TB and extensively drug-resistant TB? . . . . . . 17
 

Q&A About TB |1 

 

 

 

INTRODUCTION 


What is TB? 

Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis* . 

The bacteria usually attack the lungs . But TB bacteria can attack any part of the body 

such as the kidney, spine, and brain . If not treated properly, TB disease can be fatal . TB 

disease was once the leading cause of death in the United States . 

TB is spread through the air from one person to another . The bacteria are put into the air 

when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings . 

People nearby may breathe in these bacteria and become infected . 

However, not everyone infected with TB bacteria becomes sick . People who are 

infected, but not sick, have what is called latent TB infection . People who have latent 

TB infection do not feel sick, do not have any symptoms, and cannot spread TB to 

others . But some people with latent TB infection go on to get TB disease . 

There is good news . People with TB disease can be treated if they seek medical help . 

Even better, most people with latent TB infection can take medicine so that they will 

not develop TB disease . 

Why is TB still a problem in the United States? 

In the early 1900s, TB killed one out of every seven people living in the United States 

and Europe. Starting in the 1940s, scientists discovered the first of several medicines 

now used to treat TB . As a result, TB slowly began to decrease in the United States . But 

in the 1970s and early 1980s, the country let its guard down and TB control efforts were 

neglected . This led to an increase in the number of TB cases between 1985 and 1992 . 

However, with increased funding and attention to the TB problem, there has been a 

steady decline in the number of persons with TB since 1993 . 

TB continues to be a problem . Multidrug-resistant TB (MDR TB) remains a concern, 

and extensively drug-resistant TB (XDR TB) has become an important issue . While 

the number of TB cases in the United States has been declining, there remains a higher 

burden of TB among racial and ethnic minorities . This is due to uneven distribution of 

TB risk factors that can increase the chance of developing the disease (see page 8 for list). 

This booklet answers common questions about TB . Please ask your doctor or nurse if 

you have other questions about latent TB infection or TB disease . 

* Words that are underlined can be found in the glossary on page 18. 
2 | Q&A About TB 

How is TB spread? 

TB is spread through the air from one person to another . The bacteria are put into the air 

when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings . 

People nearby may breathe in these bacteria and become infected . 

When a person breathes in TB bacteria, the bacteria can settle in the lungs and begin to 

grow . From there, they can move through the blood to other parts of the body, such as 

the kidney, spine, and brain . 

TB disease in the lungs or throat can be 

infectious . This means that the bacteria can

be spread to other people . TB in other parts

of the body, such as the kidney or spine, is 

usually not infectious . 

People with TB disease are most likely to 

spread it to people they spend time with 

every day . This includes family members,

friends, and coworkers or schoolmates .

What is latent TB infection? 

In most people who breathe in TB bacteria and become infected, the body is able to 

fight the bacteria to stop them from growing. The bacteria become inactive, but they 

remain alive in the body and can become active later . This is called latent TB infection . 

People with latent TB infection: 

• Have no symptoms 

• Don’t feel sick 

• Can’t spread TB bacteria to others

• Usually have a positive skin test reaction or positive TB blood test (see pages 6-7) 

• May develop TB disease if they do not receive treatment for latent TB infection 

(see page 8) 

Many people who have latent TB infection never develop TB disease . In these people, 

the TB bacteria remain inactive for a lifetime without causing disease . But in other 

people, especially people who have weak immune systems, the bacteria become active, 

multiply, and cause TB disease .
Q&A About TB 3 

What is TB disease? 

If the immune system can’t stop TB bacteria from growing, the bacteria begin to 

multiply in the body and cause TB disease . The bacteria attack the body and destroy 

tissue . If this occurs in the lungs, the bacteria can actually create a hole in the lung . 

Some people develop TB disease soon after becoming infected (within weeks) before 

their immune system can fight the TB bacteria. Other people may get sick years later, 

when their immune system becomes weak for another reason . 

Babies and young children often have weak immune systems . People infected with 

HIV, the virus that causes AIDS, have very weak immune systems . Other people can 

have weak immune systems, too, especially people with any of these conditions:

• Substance abuse 

• Diabetes mellitus 

• Silicosis 

• Cancer of the head or neck 

• Leukemia or Hodgkin’s disease 

• Severe kidney disease 

• Low body weight 

• Certain medical treatments (such as corticosteroid treatment or organ transplants) 

• Specialized treatment for rheumatoid arthritis or Crohn’s disease 

Symptoms of TB disease depend on where in the body the TB bacteria are growing . 

TB disease in the lungs may cause symptoms such as: 

• A bad cough that lasts 3 weeks or longer 

• Pain in the chest 

• Coughing up blood or sputum (phlegm from deep inside the lungs) 

Other symptoms of TB disease are:

• Weakness or fatigue 

• Weight loss 

• No appetite 

• Chills 

• Fever 

• Sweating at night 

For information on how TB disease is treated, see page 12.

| 
4 Q&A About TB 

	 	 	

	 	

	 	 	 	 	

	 	

	 	 	 	

	 	 	 	 	 	 	 	 	 	

	 	 	 	

	 	 	 	 	

	 	 	 	 	 	 	 	

	 	 	 	 	 	

	 	 	 	

The Difference Between Latent TB Infection and TB Disease

A PERSON WITH LATENT TB INFECTION 

•	 Does notfeel sick

•	 Has no symptoms

•	 Cannot spread TB bacteria to others

•	 Usually has a positive TB skin test or

positive TB blood test 

•	 Has a normal chest x-ray and a negative 

sputum smear 

•	 Should considertreatmentforlatent TB		

infection to prevent TB disease 

A PERSON WITH TB DISEASE 

•	 Usually feels sick

•	 Has symptoms that may include:

- A bad cough thatlasts 3 weeks orlonger

- Pain in the chest 

- Coughing up blood or sputum 

- Weakness orfatigue

- Weight loss 

- No appetite 

- Chills 

- Fever 

- Sweating at night 

•	 May spread TB bacteria to others

•	 Usually has a positive TB skin test or

positive TB blood test 

•	 May have an abnormal chest x-ray, or

positive sputum smear or culture 

•	 Needs treatmentfor TB disease

| 
Q&A About TB |5
 
6 |	 Q&A About TB 

TESTING & TREATMENT 

Should I get tested for TB?

You should get tested for TB if 

• You have spent time with a person known or suspected to have TB disease; or 

• You have HIV infection or another condition that weakens your immune system 

and puts you at high risk for TB disease; or 

• You have symptoms of TB disease; or 

• You are from a country where TB disease is very common (most countries in Latin 

America and the Caribbean, Africa, Asia, Eastern Europe, and Russia); or 

• You live somewhere in the United States where TB disease is more common such as a 

homeless shelter, migrant farm camp, prison or jail, and some nursing homes; or 

• You inject illegal drugs . 

What are the tests for TB infection?

The TB skin test 

The TB skin test may be used to find out if you are infected with TB bacteria. You can 

get a skin test at the health department or at your doctor’s office. A health care worker 

will inject a small amount of testing fluid (called tuberculin or PPD) into the skin on the 

lower part of your arm . After 2 or 3 days, you must return to have your skin test read 

by the health care worker . You may have swelling where the tuberculin was injected . 

The health care worker will measure this swelling and tell you if your reaction to 

the test is positive or negative . A positive reaction usually means that you have been 

infected by someone with TB disease . 
Q&A About TB |7 

If you have recently been infected with TB bacteria, your TB skin test reaction may not 

be positive yet . You may need a second skin test 8 to 10 weeks after the last time you 

spent time with the person with TB disease . This is because it can take several weeks 

after infection for your immune system to react to the TB skin test . If your reaction to 

the second test is negative, you probably do not have TB infection . 

TB blood tests 

TB blood tests use a blood sample to find out if you are infected with TB bacteria. The 

tests measure the response of TB proteins when they are mixed with a small amount of 

blood . If your health department does offer the TB blood tests, only one visit is required 

to draw blood for the test . Examples of these TB blood tests include QuantiFERON®-TB 

Gold in-Tube test (QFT-GIT) and T-Spot® .TB test . 

What if I have a positive test for TB infection?

If you have a positive reaction to the TB skin test or TB blood test, your doctor or 

nurse may do other tests to see if you have TB disease . These tests usually include a 

chest x-ray . They may also include a test of the sputum you cough up . Because the TB 

bacteria may be found somewhere other than your lungs, your doctor or nurse may 

check your urine, take tissue samples, or do other tests . If you have TB disease, you will 

need to take medicine to treat the disease (see page 12). 

What if I have been vaccinated with BCG? 

BCG is a vaccine for TB . This vaccine is not widely used in the United States, but it is 

often given to infants and small children in other countries where TB is common . BCG 

vaccine does not always protect people from getting TB . 

If you were vaccinated with BCG, you may have a positive reaction to a TB skin test . 

This reaction may be due to infection with the TB bacteria . However, in some people, 

BCG may cause a positive skin test when they are not infected with TB bacteria . 

A positive reaction is more likely to mean you have been infected with TB bacteria if: 

•		 You recently spent time with a person who has TB disease; or 

•		 You are from an area of the world where TB disease is very common (such as most 

countries in Latin America and the Caribbean, Africa, Asia, Eastern Europe, and 

Russia); or 

•		 You spend time where TB disease is common (homeless shelters, migrant farm 

camps, drug-treatment centers, health care clinics, jails, prisons) . 
8 |	 Q&A About TB 

 

	 	 	 	 	 	 	 	 	 	 	 	 	

 

 

 

 

 

Unlike the TB skin test, TB blood tests are not affected by prior BCG vaccination . The TB 

blood tests are less likely to give a false-positive result in people who have received BCG . 

If I have latent TB infection, how can I keep from developing TB disease?

Many people who have latent TB infection never develop TB disease . But some people 

who have latent TB infection are more likely to develop TB disease than others . Those 

at high risk for TB disease include:

•		 People with HIV infection 

•		 People who became infected with TB bacteria in the last 

2 years 

•		 Babies and young children 

•		 People who inject illegal drugs 

•		 People who are sick with other diseases that 

weaken the immune system (see page 3) 

•		 Elderly people 

•		 People who were not treated correctly for TB in the past 

If you have latent TB infection (a positive TB skin test reaction or positive TB blood 

test) and you are in one of these high-risk groups, you need to take medicine to keep 

from developing TB disease . This is called treatment for latent TB infection . There are 

several treatment options . 

One treatment option for latent TB infection is isoniazid (INH) . Taken for 6 to 9 

months, INH kills the TB bacteria that are in the body . If you take your medicine 

as instructed by your doctor or nurse, it can keep you from developing TB disease . 

Children, adolescents, and people infected with HIV who have latent TB infection 

need to take INH for 9 months . The preferred regimen for children 2-11 years old is 9 

months of daily INH . 

Another effective treatment option for people with latent TB infection is the 12-dose 

regimen . This regimen of INH and rifapentine (RPT) is taken once a week for 3 

months under directly observed therapy (DOT) . This means the patient will meet with 

a health worker at a place they both agree on, and the health worker will observe the 

patient taking the medicine .

You and your health care provider must decide which treatment option is best for you . 

Because there are less bacteria, treatment for latent TB infection is much easier than 

treatment for TB disease . A person with TB disease has a large amount of TB bacteria 

in the body . Several drugs are needed to treat TB disease .
Q&A About TB |9 

 

Sometimes people are given treatment for latent TB infection even if their TB skin test 

reaction or TB blood test result is negative . This is often done with infants, children, 

and people infected with HIV who have recently spent time with someone with TB 

disease . This is because they are at very high risk of developing TB disease soon after 

they become infected with TB bacteria . 

If you start taking treatment for latent TB infection, you will need to see your doctor or 

nurse on a regular schedule . It is important that you take all the pills as prescribed . The 

doctor or nurse will check on how you are doing . Some people have serious side effects 

from these medicines . If you have any of the following side effects, call your doctor or 

nurse right away: 

• No appetite • Feeling itchy 

• Nausea • Skin rash 

• Vomiting • Easy bruising 

• Yellowish skin or eyes • Bleeding from gums 

• Fever for 3 or more days • Nose bleeding 

• Abdominal pain • Urine becomes dark or brown in color 

• Tingling in the fingers and toes • Aching joints 

• Pain in lower chest or heartburn • Dizziness 

WARNING:		Frequent or heavy drinking of alcoholic beverages (wine, beer, and

liquor) while taking treatment for latent TB infection can be dangerous. Check

with your doctor or nurse for more information. 

People who have latent TB infection need to know the symptoms of TB disease (see 

page 3). If they develop symptoms of TB disease, they should see a doctor right away . 

What if I have HIV infection? 

Because HIV infection weakens the immune system, people with latent TB infection 

and HIV infection are at very high risk of developing TB disease . All persons with HIV 

infection should be tested to find out if they have latent TB infection. If they have latent 

TB infection, they need treatment as soon as possible to prevent them from developing 

TB disease . If they have TB disease, they must take medicine to treat the disease . 

NOTE:TB disease can be prevented and treated, even in people withHIV infection.
10 | Q&A About TB 

 

If I was exposed to someone with TB disease, can I give TB to others? 

If you were exposed to someone with TB disease, you may become infected with TB 

bacteria, but you would not be able to spread the bacteria to others right away . Only 

persons with TB disease can spread TB to others . Before you would be able to spread 

TB bacteria to others, you would have to breathe in TB bacteria and become infected . 

Then the bacteria would have to multiply in your body and cause TB disease . At this 

point, you could possibly spread TB bacteria to others . 

Some people develop TB disease soon (within weeks) after becoming infected, before 

their immune system can fight the TB bacteria. Other people may get sick years later, 

when their immune system becomes weak for another reason . Many people with TB 

infection never develop TB disease .

In most people who breathe in TB bacteria and become infected, the body is able to 

fight the bacteria to stop them from growing. The bacteria become inactive, but they 

remain alive in the body and can become active later . This is called latent TB infection . 

People with latent TB infection cannot spread TB bacteria to others . People who have 

latent TB infection can be treated to prevent developing TB disease . 
Q&A About TB |11
 
12 | Q&A About TB 

 


 

TB DISEASE 

How is TB disease treated? 

There is good news for people with TB disease! It can almost always be treated and 

cured with medicine . But the medicine must be taken as directed by your doctor or nurse . 

If you have TB disease, you will need 

to take several different medicines . This 

is because there are many bacteria to be 

killed . Taking several medicines will do a 

better job of killing all of the bacteria and 

preventing them from becoming resistant to 

the medicines . 

The most common medicines used to treat 

TB disease are: 

• isoniazid (INH) 

• rifampin (RIF) 

• ethambutol (EMB) 

• pyrazinamide (PZA) 

If you have TB disease of the lungs or throat,

you are probably infectious . You need to stay home from work or school so that you
 

don’t spread TB bacteria to other people . After taking your medicine for a few weeks,
 

you will feel better and you may no longer be infectious to others . Your doctor or nurse
 

will tell you when you can return to work or school or visit with friends .

Having TB disease should not stop you from leading a normal life . When you are no
 

longer infectious or feeling sick, you can do the same things you did before you had
 

TB disease . The medicines that you are taking should not affect your strength, sexual
 

function, or ability to work . If you take your medicines as directed by your doctor or
 

nurse, they should kill all the TB bacteria . This will keep you from becoming sick again .
 

What are the side effects of TB disease medicines?

If you are taking medicines for TB disease, you should take it as directed by your doctor or 

nurse . The medicines may cause side effects . Some side effects are minor problems . Others 

are more serious . If you have a serious side effect, call your doctor or nurse immediately

You may be told to stop taking your medicine or to return to the clinic for tests .
Q&A About TB |13 

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

		

The side effects listed below are serious . If you have any of these symptoms, call your 

doctor or nurse immediately: 

• No appetite 

• Nausea 

• Vomiting 

• Yellowish skin or eyes 

• Fever for 3 or more days 

• Abdominal pain 

• Tingling in the fingers or toes 

• Pain in the lower chest or heart burn 

• Feeling itchy 

• Skin rash 

• Easy bruising 

• Bleeding from gums 

• Nose bleeding 

• Urine becomes dark or brown in color 

• Aching joints 

• Dizziness 

• Tingling or numbness around the mouth 

• Blurred or changed vision 

• Ringing in the ears 

• Hearing loss 

The side effects listed below are minor problems . If you have any of these side effects, 

you can continue taking your medicine . 

• Rifampin can turn urine, saliva, or tears orange . The doctor or nurse may advise 

you not to wear soft contact lenses because they may get stained . 

• Rifampin can make you more sensitive to the sun . This means you should use a 

good sunscreen and cover exposed areas so you don’t burn . 

• Rifampin makes birth control pills and implants less effective . Women who take 

rifampin should use another form of birth control .

• If you are taking rifampin as well as methadone (used to treat drug addiction), you 

may have withdrawal symptoms . Your doctor or nurse may need to adjust your 

methadone dosage .
14 | Q&A About TB 

	 	 	 	 	 	 	 	

 

	 	 	 	 	

 

Why do I need to take TB medicines regularly?

TB bacteria die very slowly . It takes at least 6 months for the medicines to kill all the 

TB bacteria . You will probably start feeling well after only a few weeks of treatment . 

But beware! The TB bacteria are still alive in your body . You must continue to take 

your medicines until all the TB bacteria are dead, even though you may feel better and 

have no more symptoms of TB disease . 

If you don’t continue taking your medicines or you aren’t taking all your medicines 

regularly, this can be very dangerous . The TB bacteria will grow and you will remain 

sick for a longer time . The bacteria may also become resistant to the medicines you 

are taking . You may need new, different medicines to kill the TB bacteria if the old 

medicines no longer work . These new medicines must be taken for a longer time and 

usually have more serious side effects . 

If you become infectious again, you could give TB bacteria to your family, friends, or 

anyone else who spends time with you . It is very important to take your medicines as 

directed by your doctor or nurse . 

What is directly observed therapy (DOT)?

The best way to remember to take your medicines is to get directly observed therapy 

(DOT) . If you get DOT, you will meet with a health care worker every day or several 

times a week . You will meet at a place you both agree on . This can be the TB clinic, 

your home or work, or any other convenient location . You will take your medicines at 

this place while the health care worker watches . 

DOT helps in several ways . The health care worker can help you remember to take 

your medicines and complete your treatment . This means you will get well as soon 

as possible . With DOT, you may need to 

take medicines only 2 or 3 times each week 

instead of every day . 

The health care worker will make sure that 

the medicines are working as they should . 

This person will also watch for side effects 

and answer questions you have about TB . 

Even if you are not getting DOT, you must 

be checked at different times to make sure 

everything is going well . You should see 

your doctor or nurse regularly while you are 

taking your medicines . This will continue 

until you are cured . 
Q&A About TB |15 

	 	 	 	 	 	 	 	 	 	 	 	 	

	 	 	 	 	 	

 

How can I remember to take my medicines if I am not on DOT?

The only way to get well is to take your medicines exactly as directed by your doctor 

or nurse . This may not be easy! You will be taking your medicines for a long time (6 

months or longer), so you should get into a routine . Here are some ways to help you 

remember to take your medicines: 

• Take your pills at the same time every day — for example, you can take them 

before eating breakfast, during a regular coffee break, or after brushing your teeth . 

• Ask a family member or a friend to remind you to take your pills . 

• Mark off each day on a calendar as you take your medicine . 

• Put your pills in a weekly pill dispenser . Keep it by your bed or in your purse 

or pocket . 

NOTE: Remember to keep all medicine out of reach of children.

If you forget to take your pills one day, skip that dose and take the next scheduled 

dose . Tell your doctor or nurse that you missed a dose . You may also call your doctor 

or nurse for instructions . 

How can I keep from spreading TB?

The most important way to keep from spreading TB is to take all your medicines, 

exactly as directed by your doctor or nurse . You also need to keep all of your clinic 

appointments! Your doctor or nurse needs to see how you are doing . You may need 

another chest x-ray or a test of the phlegm you may cough up . These tests will show 

whether the medicines are working . They will also show whether you can still give TB 

bacteria to others . Be sure to tell the doctor 

about anything you think is wrong . 

If you are sick enough with TB disease to 

go to a hospital, you may be put in a special 

room . These rooms use air vents that keep 

TB bacteria from spreading to other rooms . 

People who work in these special rooms 

must wear a special face mask to protect 

themselves from TB bacteria . You must 

stay in the room so that you will not spread 

TB bacteria to other people . Ask a nurse for 

anything you need that is not in your room . 
16	 | Q&A About TB 

		

		

If you are infectious while you are at home, there are things you can do to protect 

others near you . 

• Take your medicines as directed . This is very important! 

• Always cover your mouth with a tissue when you cough, sneeze, or laugh . Put the 

tissue in a closed bag and throw it away . 

• Do not go to work or school . Separate yourself from others and avoid close contact 

with anyone . Sleep in a bedroom away from other family members . 

• Air out your room often to the outside of the building (if it is not too cold outside) . 

TB spreads in small closed spaces where air 

doesn’t move . Put a fan in your window to 

blow out (exhaust) air that may be filled with 

TB bacteria . If you open other windows in 

the room, the fan also will pull in fresh air . 

This will reduce the chances that TB bacteria 

will stay in the room and infect someone who 

breathes the air . 

Remember, TB is spread through the air .
 

People cannot get infected with TB bacteria
 

through handshakes, sitting on toilet seats, or
 

sharing dishes and utensils with someone who
 

has TB .
 

After you take the medicines for about 2 or 3 

weeks, you may no longer be able to spread 

TB bacteria to others . If your doctor or nurse agrees, you will be able to go back 

to your daily routine, including returning to work or school . Remember, you will 

get well only if you take your medicines exactly as directed by your doctor or 

nurse . 

Think about people who may have spent time with you, such as family members, 

close friends, and coworkers. The local health department may need to test them 

for TB infection. TB is especially dangerous for children and people infected with 

HIV. If infected with TB bacteria, these people need medicine right away to keep 

from developing TB disease. 
Q&A About TB |17 

	 	 	 	 	 	 	 	

	 	

 

 

What are multidrug-resistant TB (MDR TB) and extensively drug-resistant

TB (XDR TB)?

Sometimes the TB bacteria are resistant to the medicines used to treat TB disease . This 

means that the medicine can no longer kill the bacteria . Multidrug-resistant TB, or 

MDR TB is caused by bacteria that are resistant to two or more of the most important 

TB medicines: INH and RIF . 

A more serious form of MDR TB is called extensively drug-resistant TB (XDR TB) . 

XDR TB is a rare type of TB that is resistant to nearly all medicines used to treat 

TB disease . 

If you do not take your medicines as directed by your doctor or nurse, the TB bacteria 

may become resistant to a certain medicine . Also, people who have spent time with 

someone sick with MDR TB or XDR TB disease can become infected with these 

multidrug-resistant bacteria . 

Drug resistance is more common in people who: 

• Have spent time with someone with drug-resistant TB disease; 

• Do not take all of their medicines as directed by their doctor or nurse; 

• Develop TB disease again, after having taken TB medicines in the past; or 

• Come from areas where drug-resistant TB is common . 

People with MDR TB or XDR TB disease must be treated with special medicines . 

These medicines are not as good as the usual medicines for TB, and they may cause 

more side effects . Also, people with MDR TB and XDR TB disease must see a TB 

expert who can closely observe their treatment to make sure it is working . Treatment 

takes much longer than regular TB . And, people with both MDR TB and XDR TB are 

at greater risk of dying from the disease . 
18 | Q&A About TB 

GLOSSARY OF TERMS RELATED TO TB
 

TB disease – an illness in which TB bacteria are multiplying and attacking a part of the 

body, usually the lungs . The symptoms of TB disease include weakness, weight loss, 

fever, no appetite, chills, and sweating at night . Other symptoms of TB disease depend 

on where in the body the bacteria are growing . If TB disease is in the lungs (pulmonary 

TB), the symptoms may include a bad cough, pain in the chest, or coughing up blood . A 

person with TB disease may be infectious and spread TB bacteria to others . 

BCG – a vaccine for TB named after the French scientists who developed it, Calmette 

and Guérin . BCG is rarely used in the United States, but it is often given to infants and 

small children in other countries where TB is common . 

Chest x-ray – a picture of the inside of your chest . A chest x-ray is made by exposing a 

film to x-rays that pass through the chest. A doctor can look at this film to see whether 

TB bacteria have damaged the lungs . 

Contact – a person who has spent time with a person with infectious TB . 

Culture – a test to see whether there are TB bacteria in your phlegm or other body 

fluids. This test can take 2 to 4 weeks in most laboratories. 

Directly observed therapy (DOT) – a way of helping patients take their medicines for 

TB . If you get DOT, you will meet with a health care worker every day or several times 

a week . You will meet at a place you both agree on . This can be the TB clinic, your 

home or work, or any other convenient location . You will take your medicines while the 

health care worker watches . 

Extensively drug-resistant TB (XDR TB) - XDR TB is a rare type of TB disease that is 

resistant to nearly all medicines used to treat TB . 
Q&A About TB |19 

Extrapulmonary TB – TB disease in any part of the body other than the lungs (for 

example, the kidney, spine, brain, or lymph nodes) . 

HIV infection – infection with the human immunodeficiency virus, the virus that causes 

AIDS (acquired immunodeficiency syndrome). A person with both latent TB infection 

and HIV infection is at very high risk for developing TB disease . 

Isoniazid (INH)		– a medicine used to prevent TB disease in people who have latent TB 

infection . INH is also one of the four medicines often used to treat TB disease . 

Latent TB infection – a condition in which TB bacteria are alive, but inactive in the 

body . People with latent TB infection have no symptoms, don’t feel sick, can’t spread 

TB bacteria to others, and usually have a positive TB test . But they may develop TB 

disease if they do not receive treatment for latent TB infection . 

Multidrug-resistant TB (MDR TB) – TB disease caused by bacteria resistant to two or 

more of the most important medicines: INH and RIF . 

Mycobacterium tuberculosis – bacteria that cause latent TB infection and TB disease . 

Negative – usually refers to a test result . If you have a negative TB skin test reaction or 

TB blood test, you probably do not have TB infection . 

Positive – usually refers to a test result . If you have a positive TB skin test reaction or 

TB blood test, you probably have TB infection . 

Pulmonary TB – TB disease that occurs in the lungs, usually producing a cough that 

lasts 3 weeks or longer . Most TB disease is pulmonary . 

Resistant bacteria – bacteria that can no longer be killed by a certain medicine . 
20 | Q&A About TB 

	 		

 

Rifampin (RIF) – one of the four medicines often used to treat TB disease . 

Rifapentine (RPT) – one of two medicines used to treat latent TB infection . 

Smear – a test to see whether there are TB bacteria in your phlegm (sputum) . To do this 

test, lab workers smear the sputum on a glass slide, stain the slide with a special dye, 

and look for any TB bacteria on the slide . This test usually takes 1 day to get the results . 

Sputum – phlegm coughed up from deep inside the lungs . Sputum is examined for TB 

bacteria using a smear; part of the sputum can also be used to do a culture . 

TB skin test – a test that is often used to find out if you are infected with TB bacteria. 

A liquid called tuberculin is injected into the skin on the lower part of your arm . If you 

have a positive reaction to this test, you probably have TB infection . Other tests will be 

needed to find out if you have latent TB infection or TB disease. 

TB blood test – a test that uses a blood sample to find out if you are infected with TB 

bacteria . The test measures the response to TB proteins when they are mixed with a 

small amount of blood . Examples of these TB blood tests include QuantiFERON®-TB 

Gold In-Tube test (QFT-GIT) and T-Spot® .TB test . 

Tuberculin or PPD – a liquid that is injected into the skin on the lower part of your 

arm during a TB skin test . If you have TB infection, you will probably have a positive 

reaction to the tuberculin . 

For more information 

or to order educational materials about TB, 

contact your local Health Department 

Or visit: 

CDC Division of Tuberculosis Elimination Website 

www.cdc.gov/tb 

14_249164