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

Division of Tuberculosis Elimination

TB Elimination

Extensively Drug-Resistant Tuberculosis (XDR TB)

What is Extensively Drug-Resistant 

Tuberculosis (XDR TB)?

Extensively drug resistant TB (XDR TB) is a rare 

type of multidrug-resistant tuberculosis (MDR 

TB) that is resistant to isoniazid and rifampin, 

plus any fluoroquinolone and at least one of 

three injectable second-line drugs (i.e., amikacin, 

kanamycin, or capreomycin). MDR TB is caused by 

an organism that is resistant to at least isoniazid 

and rifampin, the two most potent TB drugs.

How is XDR TB spread? 

Drug-susceptible TB and XDR TB are spread the 

same way. TB bacteria are put into the air when 

a person with TB disease of the lungs or throat 

coughs, sneezes, shouts, or sings. These bacteria 

can float in the air for several hours, depending 

on the environment. Persons who breathe 

in the air containing these TB bacteria can 

become infected. 

TB is not spread by

• shaking someone’s hand 

• sharing food or drink 

• touching bed linens or toilet seats 

• sharing toothbrushes 

• kissing 

Why is XDR TB so serious?

Because XDR TB is resistant to the most potent 

TB drugs, the remaining treatment options are 

less effective, have more side effects, and are 

more expensive. XDR TB is of special concern for 

persons with HIV infection or other conditions 

that can weaken the immune system. These 

persons are more likely to develop TB disease 

once they are infected, and they also have a 

higher risk of death if they develop TB disease.

Who is at risk for getting XDR TB?

Drug-resistant TB (MDR or XDR) is more common 

in people who:

• Do not take their TB medicine regularly 

• Do not take all of their TB medicines as 

prescribed by their doctor

• Develop TB disease again, after having taken TB 

medicine in the past 

• Come from areas of the world where drugresistant TB is common 

• Have spent time with someone known to have 

drug-resistant TB disease 

How can I prevent myself from 

getting TB?

Avoid close contact for a prolonged period of 

time with known TB patients in crowded, enclosed 

environments like clinics, hospitals, prisons, or 

homeless shelters.

Can the TB vaccine (BCG) help prevent 

XDR TB?

The TB vaccine is called Bacille Calmette-Guérin 

(BCG), and it is used in many countries to prevent 

severe forms of TB in children. However, BCG is 

not generally recommended in the United States 

because it has limited effectiveness for preventing 

the most common forms of TB and in preventing 

TB in adults. The effect of BCG against XDR TB 

would likely be similar to the effect on drugsusceptible TB.

If I have drug-susceptible TB, how can 

I prevent getting drug-resistant TB?

The most important thing is for you to continue 

taking all your TB medicines exactly as prescribed. 

No doses should be missed and treatment should 
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not be stopped early. You should tell your health 

care provider if you are having trouble taking the 

medications or if you have any side effects. If you 

plan to travel, talk with your health care provider, 

and make sure you have enough medicine to last 

while away.

Can XDR TB be treated and cured?

Yes, in some cases. Some TB control programs 

have shown that cure is possible for an estimated 

30% to 50% of affected people. Successful 

outcomes depend greatly on the extent of the 

drug resistance, the severity of the disease, 

whether the patient’s immune system is 

weakened, and adherence to treatment.

What are the symptoms of XDR TB?

The general symptoms of TB disease include 

feelings of sickness or weakness, weight loss, fever, 

and night sweats. The symptoms of TB disease of 

the lungs may also include coughing, chest pain, 

and coughing up blood. Symptoms of TB disease 

in other parts of the body depend on the area 

affected. If you have these symptoms, you should 

contact your doctor or local health department.

What should I do if I have been 

around someone who has XDR TB?

If you think you have been exposed to someone 

with XDR TB disease, you should contact your 

doctor or local health department about getting 

a TB skin test or blood test for TB infection. You 

should tell the doctor or nurse when you spent 

time with this person. You should also tell the 

doctor or nurse where the person with XDR TB is 

being treated. It will be important to know about 

this person’s treatment. If your test for TB infection 

is positive, you will need special follow up. 

How long does it take to find out if 

you have XDR TB?

If TB bacteria are found in the sputum (phlegm), 

the diagnosis of TB can be made in a day or two, 

but this finding will not be able to distinguish 

between drug-susceptible TB and drug-resistant 

TB. To determine drug susceptibility, the bacteria 

need to be grown and tested in a specialized 

laboratory. Final diagnosis for TB, and especially 

for XDR TB, may take from 6 to 16 weeks.

Is XDR TB a problem in the U.S?

The risk of acquiring XDR TB in the United States 

appears to be low because XDR TB is uncommon 

in the U.S. However, TB can spread easily. As long 

as XDR TB exists, the risk to people in the United 

States is not zero, and the U.S. public health 

system must address the threat.

How many cases of XDR TB have been 

reported in the U.S.?

In the United States, 63 cases of XDR TB have been 

reported between 1993 and 2011*. 

*The National Tuberculosis Surveillance System (NTSS) 1993-2011.

Is it safe to travel to countries where 

cases of XDR TB have been reported?

Although MDR and XDR TB are occurring globally, 

they are still rare. HIV-infected travelers are at 

greatest risk if they come in contact with a person 

with MDR or XDR TB.

All travelers should avoid high risk settings where 

there are no infection control measures in place. 

Documented places where transmission has 

occurred include crowded hospitals, prisons, 

homeless shelters, and other settings where 

susceptible persons come in contact with persons 

with TB disease.

What can health care providers do to 

prevent XDR TB?

Health care providers can help prevent MDR and 

XDR TB by quickly diagnosing TB cases, following 

recommended treatment guidelines, monitoring 

patients’ response to treatment, and making sure 

therapy is completed.
January 2013

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Providers should also ensure proper 

implementation of infection control procedures 

to prevent exposure to TB in hospitals or healthcare settings where TB patients are likely to 

be seen.

Why does there seem to be more 

cases of XDR TB now than there were 

in the past? 

In 2006, CDC, the World Health Organization 

(WHO), and other global leaders in TB reported 

the results of a survey regarding drug-resistant 

TB conducted by 25 reference laboratories 

comprising the Global Supranational TB 

Reference Laboratory Network, the National TB 

Surveillance System in the United States, the 

national reference laboratory of South Korea, and 

the national MDR TB patient registry in Latvia. 

The findings indicated that 20% of M. tuberculosis

isolates were MDR, and 2% also were resistant to 

many additional TB drugs. This highly resistant 

form of TB was identified in every region of the 

world where there was lab capacity to identify it. 

In a report published in 2006, the highly resistant 

form of TB was named XDR TB. Since then, more 

countries have improved their laboratory capacity 

to test for XDR TB and their ability to report 

XDR TB. These factors have contributed to an 

apparent increase in drug-resistant TB because of 

better diagnosis and better reporting.

What is CDC doing to prevent TB 

from becoming a bigger problem 

both domestically and globally?

CDC is collaborating with other federal agencies 

and international partners to raise awareness 

and enhance strategies for TB prevention 

worldwide by: 

• Strengthening TB services for people living 

with HIV/AIDS; 

• Guiding preparedness and outbreak 

investigation responses;

• Improving access to TB drugs; 

• Conducting routine surveillance (including 

drug susceptibility) and periodic surveys;

• Implementing new, rapid diagnostic tests;

• Developing and promoting, national and 

international TB testing standards; 

• Conducting program evaluation (e.g., National 

TB Indicators Project [NTIP]);

• Building capacity of health care providers to 

diagnose and treat TB; 

• Reinvigorating the Federal TB Task Force;

• Providing assistance to improve TB program 

capacity in the U.S. and abroad; and

• Developing education, risk, and media 

communications (Web- and print-based) to aid 

in preparedness and public awareness of TB 

prevention and control issues. 

Additional Information

1. CDC. Extensively Drug-Resistant Tuberculosis 

Information. http://www.cdc.gov/tb/topic/drtb/

xdrtb.htm

2. CDC. Questions and Answers About TB.

http://www.cdc.gov/tb/publications/faqs/

default.htm

3. CDC. Tuberculosis: General Information.

http://www.cdc.gov/tb/publications/factsheets/

general/tb.htm

4. CDC. Multidrug Resistant Tuberculosis.

http://www.cdc.gov/tb/publications/factsheets/

drtb/mdrtb.htm

5. CDC. Tuberculosis Information for International 

Travelers. http://www.cdc.gov/tb/publications/

factsheets/general/tbtravelinfo.htm

6. CDC. Extensively Drug-Resistant Tuberculosis–

United States, 1993—2006. 

http://www.cdc.gov/mmwr/preview/

mmwrhtml/mm5611a3.htm

7. CDC. CDC’s Role in Preventing XDR TB. 

http://www.cdc.gov/tb/publications/factsheets/

drtb/cdcandxdrtb.htm

http://www.cdc.gov/tb