Tuberculosis
- Topics
- Basic TB Facts
- Treatment
- Testing & Diagnosis
- TB & HIV Coinfection
- Infection Control & Prevention
- Drug-Resistant TB
- TB in Specific Populations
- African-American Community
- Correctional Facilities
- Table of Contents
- Introduction
- Strengthen TB Information Systems and Program Assessment
- Strengthen TB Environmental Controls and Isolation Practices
- Provide More Comprehensive and Timely Screening and Diagnostic Evaluations
- Develop and Strengthen Contact Investigation Protocols
- Increase HIV Counseling and Testing
- Increase Staff Training
- Strengthen Collaboration Between Health Departments and Jails
- International Travelers
- Pregnancy
- Disaster Responders
- Children
- Vaccines & Immunizations
- Laboratory Information
- Drug Susceptibility Testing
- The Uses of Nucleic Acid Amplification Tests for the Diagnosis of TB
- Rapid Molecular Testing to Detect Drug-Resistant TB in the US
- Executive Summary
- Introduction
- Background on Tests for Molecular Detection of DR
- General Considerations and Principles for a Molecular DR Testing Service�
- Possible Scenarios and Scope of Testing for a Molecular DR Testing Service
- Research Needs
- General Recommendations of the Expert Panel
- Communication Plan for the Report
- Recommendations
- References
- Panel Members and CDC Participants
- Appendix 1
- Appendix 2
- Appendix 3
- Interim Laboratory Biosafety Guidance for XDR Mycobacterium tuberculosis strains
- Molecular Detection of Drug Resistance (MDDR)
- Research
- TB Epidemiologic Studies Consortium
- Background
- Infrastructure
- Research Projects
- Publications
- Meetings
- Directory
- TBESC Committee Members
- Translating Research into Practice (TRIP)
- Contact TBESC
- Prospective Evaluation of Immunogenetic and Immunologic Markers for Susceptibility to Tuberculosis Infection and Progression from M. Tuberculosisinfection to active TB
- Zero Tolerance for Pediatric TB
- Models for Incorporating HIV Counseling, Testing, and Referral into Tuberculosis Contact Investigations
- Prevalence of Latent TB Infection Among High Risk Populations in the United States
- Regional Capacity-Building in Low-Incidence Areas
- Use of Network Analysis Methods to Characterize M. tuberculosis Transmission Patterns Among Women and Other High-Risk Populations
- An Analysis of Molecular Epidemiology of Multi-Drug Resistant M. tuberculosisin the United States
- Missed Opportunities for TB Prevention in Foreign-Born Population in the United States and Canada
- New Model for Assessing TB Surveillance and Action Performance and Cost
- Addressing TB Among African Americans in the Southeast: Identifying and Overcoming Barriers to Treatment Adherence for Latent TB Infection and TB Disease
- Assessing the TB Knowledge, Attitudes, Beliefs, and Practices Among Private Providers Serving Foreign-born Populations at Risk for TB
- Factors Associated with Acceptance of, Adherence to and Toxicity From Treatment for Latent TB Infection and Pilot Study of Treatment for Latent TB Infection Effectiveness
- Culturally Appropriate TB Educational Materials for Leaders and Staff of Hispanic Service Organizations
- Enhancing TB Programs� Capacity for Self-Evaluation: Testing New Tools and Developing an Evaluation Toolkit
- African Refugee Women�s Health Improvement Project
- Evaluation of the TK Medium: A New Rapid Solid Culture System for Tuberculosis
- Evaluation of New Interferon-y Release Assays in the Diagnosis of Latent TB Infection in Health Care Workers
- Request for Proposal
- TB Trials Consortium
- Behavioral & Social Science Research
- TB Epidemiologic Studies Consortium
- Data & Statistics
- Education & Training
- Resources for TB Programs
- Publications & Products
- Fact Sheets
- General
- Fact sheets - Spanish
- TB - General Information
- The Difference Between Latent TB Infection and Active TB Disease
- Diferencia entre la infección de tuberculosis latente y enfermedad de tuberculosis activa
- A Global Perspective on TB
- Tuberculosis Information for Employers in Non-Healthcare Settings
- Bovine Tuberculosis in Humans
- Tuberculosis Information for International Travelers
- TB Can Be Treated
- Exposure to TB
- TB and HIV/AIDS
- You Can Prevent TB
- Testing for TB
- Tuberculosis: informaci�n general
- Diferencia entre la infecci�n de tuberculosis latente y enfermedad de tuberculosis activa
- Informaci�n sobre la tuberculosis para los viajeros internacionales
- Exposición a la tuberculosis
- Usted puede prevenir la tuberculosis
- La tuberculosis puede ser tratada
- Tuberculosis y VIH/SIDA
- Usted puede prevenir la tuberculosis
- Pruebas para detectar la tuberculosis
- Data & Statistics
- A Global Perspective on TB
- Trends in Tuberculosis – United States
- The Revised Report of Verified Case of Tuberculosis
- The National Tuberculosis Indicators Project (NTIP)
- National Tuberculosis Indicators Project (NTIP): Frequently Asked Questions
- TB Genotyping
- TB Genotyping Information Management System (TB GIMS)
- Drug-Resistant TB
- Multidrug-Resistant Tuberculosis (MDR TB)
- Extensively Drug-Resistant Tuberculosis (XDR TB)
- CDC’s Role in Preventing Extensively Drug-Resistant Tuberculosis (XDR TB)
- Tuberculosis multirresistente (MDR)
- Tuberculosis extremadamente resistente (XDR)
- El papel de los CDC en la prevenci�n de la tuberculosis extremadamente resistente (XDR)
- Infection Control & Prevention
- TB in Specific Populations
- Tuberculosis Information for Employers in Non-Healthcare Settings
- Tuberculosis in Minorities
- Tuberculosis Information for International Travelers
- TB and HIV/AIDS
- Recommendations for Human Immunodeficiency Virus (HIV) Screening in Tuberculosis (TB) Clinics
- Treatment of Drug-Susceptible Tuberculosis Disease in HIV-Infected Persons
- Tuberculosis in Blacks
- Tuberculosis and Pregnancy
- Tuberculosis y embarazo
- Treatment
- TB Can Be Treated
- Treatment of Latent TB Infection
- Treatment of Latent Tuberculosis Infection: Maximizing Adherence
- Treatment Options for Latent Tuberculosis Infection
- Treatment of Drug-Resistant Tuberculosis
- Treatment of Drug-Susceptible Tuberculosis Disease in Persons Not Infected with HIV
- Treatment of Drug-Susceptible Tuberculosis Disease in HIV-Infected Persons
- Tratamiento de la infecci�n de tuberculosis latente
- Testing & Diagnosis
- TB Can Be Treated
- Testing for TB
- Recommendations for Human Immunodeficiency Virus (HIV) Screening in Tuberculosis (TB) Clinics
- Interferon-Gamma Release Assays (IGRAs)
- Tuberculin Skin Testing
- Diagnosis of Tuberculosis Disease
- Targeted Tuberculin Testing and Interpreting Tuberculin Skin Test Results
- Prueba cutánea de la tuberculina
- Diagnóstico de la tuberculosis activa
- Vaccines & Immunizations
- General
- Guidelines
- Guides & Toolkits
- Core Curriculum
- Self-Study Modules
- Report of Verified Case of Tuberculosis (RVCT)
- Forging Partnerships to Eliminate TB
- Understanding the TB Cohort Review Process
- Latent Tuberculosis Infection: A Guide for Primary Health Care Providers
- Effective TB Interviewing for Contact Investigation
- Mantoux Tuberculin Skin Testing Products
- Ethnographic Guides
- Newsletters
- Pamphlets, Brochures, Booklets
- Posters
- Mantoux Tuberculin Skin Test Wall Chart
- World TB Day
- Afiches
- 2011 Poster (English)
- 2011 Poster (Spanish)
- 2010 Poster (English)
- 2010 Poster (Spanish)
- 2008 Poster (English)
- 2008 Poster (Spanish)
- 2006 Poster (English)
- 2004 Poster (English)
- 2004 Poster (Spanish)
- 2003 Poster (English)
- 2003 Poster (Spanish)
- 2003 Now is the Time Poster (English)
- 2003 Now is the Time Poster (Spanish)
- Think TB
- Stop TB
- Reports & Articles
- Morbidity and Mortality Weekly Reports (MMWRs)
- Contact Investigations
- Control and Elimination
- Data & Statistics
- Drug-Resistant Tuberculosis
- Infection Control & Prevention
- Laboratory
- TB in Specific Populations
- Foreign-Born
- High-Risk Settings
- Homeless
- International
- Occupational Groups
- Travel
- TB & HIV
- Testing & Diagnosis
- Treatment
- LTBI Updates
- Vaccines & Immunizations
- World TB Day
- DTBE Authored Journal Articles
- Tuberculosis Laboratory Aggregate Reports
- Morbidity and Mortality Weekly Reports (MMWRs)
- Slide Sets
- Core Curriculum
- Self-Study Modules
- Prevention and Control of Tuberculosis in Correctional and Detention Facilities
- Guidelines for Preventing the Transmission of M. TB in Health care Settings
- Investigation of Contacts of Persons with Infectious TB
- Text-Only version
- Introduction
- Decisions to Initiate a Contact Investigation
- Investigating the Index Patient and Sites of Transmission
- Assigning Priorities to Contacts
- Diagnostic and Public Health Evaluation of Contacts
- Medical Treatment for Contacts with LTBI
- When to Expand a Contact Investigation
- Communicating Through the News Media
- Data Management and Evaluation of Contact Investigations
- Confidentiality and Consent in Contact Investigations
- Staff Training for Contact Investigations
- Contact Investigations in Special Circumstances
- Source-Case Investigations
- Cultural Competency and Social Network Analysis
- Resources
- Epidemiology of Pediatric Tuberculosis in the United States
- Text-Only version
- Introduction
- Pediatric TB Cases by Age and Race
- Pediatric TB Cases by Origin of Birth
- Pediatric Cases, Percentages and Rates by States
- Pediatric TB Cases by Case Verification Criterion and Site of Disease
- Pediatric TB Cases in Specific Groups
- Pediatric TB Cases Case Completion
- Slide 1
- Slide 2
- Slide 3
- Slide 4
- Slide 5
- Slide 6
- Slide 7
- Slide 8
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- Slide 10
- Slide 11
- Slide 12
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- Slide 18
- Slide 19
- Slide 20
- Slide 21
- Slide 22
- Slide 23
- Slide 24
- Slide 25
- Slide 26
- Slide 27
- Slide 28
- Slide 29
- Slide 30
- Slide 31
- Treatment of TB
- Targeted Tuberculosis Testing and Treatment of Latent Tuberculosis Infection
- CD Roms
- Electronic Tools & Resources
- Web-Based Courses & Webinars
- Fact Sheets
- Global TB
- Events
- Links
- About Us
- Mission Statement and Activities
- Organization Chart
- Advisory Groups
- Federal TB Task Force
- Table of Contents
- Executive Summary
- Introduction
- Chronology in the Development of This Report
- Strategies for Maintaining Control of TB
- Strategies for Accelerating the Decline of TB
- Activities for Developing New Tools
- Global U.S. Actions
- Assessing the Impact of Actions Taken
- Federal TB Task Force Members and Others Involved in the Development of This Report
- Glossary
- References
- Federal TB Task Force Roster
- Table of Contents
- Executive Summary
- Introduction
- How to Eliminate TB? – The IOM Report
- Why Eliminate TB? – Rationale for Elimination
- Who Will Lead? – CDC's Response
- Goal I: Maintain control of TB
- Goal II: Accelerate the decline
- Goal III: Create new tools
- Goal IV: Reduce the global burden of TB
- Goal V: Summon and sustain support
- Goal VI: Track progress
- References
- Federal TB Task Force
- Funding
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Testing & Diagnosis
Testing for TB Infection
Tuberculosis (TB) is a disease that is spread through the air from one person to another. There are two kinds of tests that are used to determine if a person has been infected with TB bacteria: the tuberculin skin test and TB blood tests.
A positive TB skin test or TB blood test only tells that a person has been infected with TB bacteria. It does not tell whether the person has latent TB infection (LTBI) or has progressed to TB disease. Other tests, such as a chest x-ray and a sample of sputum, are needed to see whether the person has TB disease.
Tuberculin skin test: The TB skin test (also called the Mantoux tuberculin skin test) is performed by injecting a small amount of fluid (called tuberculin) into the skin in the lower part of the arm. A person given the tuberculin skin test must return within 48 to 72 hours to have a trained health care worker look for a reaction on the arm. The health care worker will look for a raised, hard area or swelling, and if present, measure its size using a ruler. Redness by itself is not considered part of the reaction.
The skin test result depends on the size of the raised, hard area or swelling. It also depends on the person’s risk of being infected with TB bacteria and the progression to TB disease if infected.
- Positive skin test: This means the person’s body was infected with TB bacteria. Additional tests are needed to determine if the person has latent TB infection or TB disease. A health care worker will then provide treatment as needed.
- Negative skin test: This means the person’s body did not react to the test, and that latent TB infection or TB disease is not likely.
TB blood tests: TB blood tests (also called interferon-gamma release assays or IGRAs) measure how the immune system reacts to the bacteria that cause TB. An IGRA measures how strong a person’s immune system reacts to TB bacteria by testing the person’s blood in a laboratory.
Two IGRAs are approved by the U.S. Food and Drug Administration (FDA) and are available in the United States:
- QuantiFERON®–TB Gold In-Tube test (QFT-GIT)
- T-SPOT®.TB test (T-Spot)
- Positive IGRA: This means that the person has been infected with TB bacteria. Additional tests are needed to determine if the person has latent TB infection or TB disease. A health care worker will then provide treatment as needed.
- Negative IGRA: This means that the person’s blood did not react to the test and that latent TB infection or TB disease is not likely.
IGRAs are the preferred method of TB infection testing for the following:
- People who have received bacille Calmette–Guérin (BCG). BCG is a vaccine for TB disease.
- People who have a difficult time returning for a second appointment to look for a reaction to the TST.
There is no problem with repeated IGRAs.
Who Should Get Tested for TB
TB tests are generally not needed for people with a low risk of infection with TB bacteria.
Certain people should be tested for TB bacteria because they are more likely to get TB disease, including:
- People who have spent time with someone who has TB disease
- People with HIV infection or another medical problem that weakens the immune system
- People who have symptoms of TB disease (fever, night sweats, cough, and weight loss)
- People from a country where TB disease is common (most countries in Latin America, the Caribbean, Africa, Asia, Eastern Europe, and Russia)
- People who live or work somewhere in the United States where TB disease is more common (homeless shelters, prison or jails, or some nursing homes)
- People who use illegal drugs
Testing for TB in BCG-Vaccinated Persons
Many people born outside of the United States have been BCG-vaccinated.
People who have had a previous BCG vaccine may receive a TB skin test. In some people, BCG may cause a positive skin test when they are not infected with TB bacteria. If a TB skin test is positive, additional tests are needed.
IGRAs, unlike the TB skin tests, are not affected by prior BCG vaccination and are not expected to give a false-positive result in people who have received BCG.
Choosing a TB Test
The person’s health care provider should choose which TB test to use. Factors in selecting which test to use include the reason for testing, test availability, and cost. Generally, it is not recommended to test a person with both a TST and an IGRA.
Diagnosis of Latent TB Infection or TB Disease
If a person is found to be infected with TB bacteria, other tests are needed to see if the person has TB disease.
TB disease can be diagnosed by medical history, physical examination, chest x-ray, and other laboratory tests. TB disease is treated by taking several drugs as recommended by a health care provider.
If a person does not have TB disease, but has TB bacteria in the body, then latent TB infection is diagnosed. The decision about treatment for latent TB infection will be based on a person’s chances of developing TB disease.
Diagnosis of TB Disease
People suspected of having TB disease should be referred for a medical evaluation, which will include
- Medical history,
- Physical examination,
- Test for TB infection (TB skin test or TB blood test),
- Chest radiograph (X-ray), and
- Appropriate laboratory tests
See Diagnosis of TB (Fact sheet) for more information about TB diagnosis.
Related Links
For Patients
- TB – General Information (Fact sheet)
- Testing for Tuberculosis (TB) (Fact Sheet – PDF 306kb)
- What You Need to Know About the TB Skin Test (Pamphlet – PDF 202k)
- Questions and Answers About TB
For Health Care Providers
- What's New in Blood Testing for TB Infection? (video)
- Testing and Diagnosis Fact sheets
- Testing and Diagnosis Guidelines
- TB Testing MMWRs
- Education and Training Products
- Tuberculin Skin Testing (fact sheet)
- Tuberculosis and Pregnancy (fact sheet)
- Mantoux Tuberculin Skin Testing Materials
- General information about TB blood tests
- Interferon-Gamma Release Assays (fact sheet)
Contact Us:
- Centers for Disease Control and Prevention
Division of Tuberculosis Elimination (DTBE)
1600 Clifton Rd., NE
MS E10
Atlanta, GA 30333 - 800-CDC-INFO
(800-232-4636)
TTY: (888) 232-6348 - New Hours of Operation
8am-8pm ET/Monday-Friday
Closed Holidays - cdcinfo@cdc.gov