Table of ContentsView AllTable of ContentsSymptomsCausesDiagnosisTreatmentPrevention
Table of ContentsView All
View All
Table of Contents
Symptoms
Causes
Diagnosis
Treatment
Prevention
The typical symptoms of activetuberculosis(TB)affect the lungs and throat and include chronic cough, sputum (thick, colored phlegm), and blood while coughing, among others. However, most people exposed—approximately nine in 10—have latent TB, meaning they aren’t symptomatic or contagious.
Though closely related, there are key differences between active and latent TB. This article discusses these distinctions and provides an overview of their symptoms, causes, and treatment, as well as what you can do to prevent exposure.
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Though both latent and active TB arise from exposure to bacteria, there are key differences in how these conditions present. Active TB causes symptoms and can spread, while latent TB doesn’t cause any physical signs or symptoms and is not contagious.
Latent TBNo outward signs or symptomsInfection only detectable using a blood or skin TB testLatent TB is not contagious
No outward signs or symptoms
Infection only detectable using a blood or skin TB test
Latent TB is not contagious
Symptoms include chronic cough, blood or sputum while coughing, chest pain,
fatigue, muscle weakness,
loss of appetite, weight loss, chills, fever, and night sweats
Infection detectable through sputum samples, blood or skin TB tests, or a chest X-ray
Given this means of transmission, your chances of exposure to TB increase when you spend significant periods of time close to a symptomatic person. For example, cases often spread among family members, classmates, co-workers, and friends.
Latent TB
Most people exposed to TB can successfully contain and control the infection. The key difference between active and latent TB hinges on theimmune systemand its ability to prevent the infection from spreading.Put simply, those with stronger immunity are better able to stop the disease from becoming serious; however, they will still have small amounts of the bacteria in their systems.
Active TB
Roughly 5–10% of those exposed to TB bacteria develop active forms of the disease.Several risk factors that make some more susceptible to developing symptoms include:
During diagnosis, healthcare providers want to ensure symptoms are the result of TB and not another condition and assess how much the disease has spread and developed. Several tests can help with diagnosis.
Latent TB Diagnosis
Latent TB is more difficult to diagnose because many people carry it without knowing it. Only two tests can detect both latent and active cases. These include:
Active TB Diagnosis
Additional tests and evaluations that can detect active TB include:
Screening for Drug-Resistant TBIn some cases, TB bacteria can become resistant to antibiotics, rendering these medications ineffective. Your healthcare provider will monitor you closely and check for drug sensitivity to assess your individual treatment needs.
Screening for Drug-Resistant TB
In some cases, TB bacteria can become resistant to antibiotics, rendering these medications ineffective. Your healthcare provider will monitor you closely and check for drug sensitivity to assess your individual treatment needs.
Three- to nine-monthantibiotic drugregimenstreatlatent and active TB.
Latent TB Treatments
Though people with latent TB don’t have symptoms and aren’t contagious, treatment is still necessary to prevent it from becoming active. Weight, age, and other health factors determine specific dosages, with typical approaches including:
Short-course three- to four-month rifamycin-based treatment is preferable to six- to nine-month isoniazid therapy.
Active TB treatments
As with latent TB, prolonged courses of antibiotic therapy treat active cases. Primarily, there are two combination therapies, with specific dosages shifting throughout treatment. These include:
Treatments for Special PopulationsTB progression can become much more severe among specific populations, such as immunocompromised people, children and infants, and older adults. Courses of therapy may need some adjustment in these cases.
Treatments for Special Populations
TB progression can become much more severe among specific populations, such as immunocompromised people, children and infants, and older adults. Courses of therapy may need some adjustment in these cases.
Summary
Latent and active tuberculosis (TB) are two forms of bacterial infection, fromMycobacterium tuberculous.Most exposed people have latent TB, meaning they are without symptoms and not contagious.
Active TB occurs when bacteria are multiplying in the body, leading to chronic cough, blood or sputum while coughing, chills, and other symptoms.These conditions are treated with prolonged courses of antibiotic therapy. Timely diagnosis is essential in their management.
8 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Carranza C, Pedraza-Sanchez S, de Oyarzabal-Mendez E, et al.Diagnosis for latent tuberculosis infection: new alternatives.Front Immunol. 2020;11. doi:10.3389/fimmu.2020.02006Centers for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.Muñoz L, Stagg HR, Abubakar I.Diagnosis and management of latent tuberculosis infection.Cold Spring Harb Perspect Med. 2015;5(11):a017830. doi:10.1101/cshperspect.a017830Centers for Disease Control and Prevention.Treatment for TB disease.Centers for Disease Control and Prevention.Treatment regimens for latent TB infection.Centers for Disease Control and Prevention.Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues.US Preventive Services Task Force, Mangione CM, Barry MJ, et al.Screening for Latent Tuberculosis Infection in Adults: US Preventive Services Task Force Recommendation Statement.JAMA. 2023;329(17):1487-1494. doi:10.1001/jama.2023.4899Additional ReadingCenters for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.
8 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Carranza C, Pedraza-Sanchez S, de Oyarzabal-Mendez E, et al.Diagnosis for latent tuberculosis infection: new alternatives.Front Immunol. 2020;11. doi:10.3389/fimmu.2020.02006Centers for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.Muñoz L, Stagg HR, Abubakar I.Diagnosis and management of latent tuberculosis infection.Cold Spring Harb Perspect Med. 2015;5(11):a017830. doi:10.1101/cshperspect.a017830Centers for Disease Control and Prevention.Treatment for TB disease.Centers for Disease Control and Prevention.Treatment regimens for latent TB infection.Centers for Disease Control and Prevention.Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues.US Preventive Services Task Force, Mangione CM, Barry MJ, et al.Screening for Latent Tuberculosis Infection in Adults: US Preventive Services Task Force Recommendation Statement.JAMA. 2023;329(17):1487-1494. doi:10.1001/jama.2023.4899Additional ReadingCenters for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Carranza C, Pedraza-Sanchez S, de Oyarzabal-Mendez E, et al.Diagnosis for latent tuberculosis infection: new alternatives.Front Immunol. 2020;11. doi:10.3389/fimmu.2020.02006Centers for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.Muñoz L, Stagg HR, Abubakar I.Diagnosis and management of latent tuberculosis infection.Cold Spring Harb Perspect Med. 2015;5(11):a017830. doi:10.1101/cshperspect.a017830Centers for Disease Control and Prevention.Treatment for TB disease.Centers for Disease Control and Prevention.Treatment regimens for latent TB infection.Centers for Disease Control and Prevention.Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues.US Preventive Services Task Force, Mangione CM, Barry MJ, et al.Screening for Latent Tuberculosis Infection in Adults: US Preventive Services Task Force Recommendation Statement.JAMA. 2023;329(17):1487-1494. doi:10.1001/jama.2023.4899
Carranza C, Pedraza-Sanchez S, de Oyarzabal-Mendez E, et al.Diagnosis for latent tuberculosis infection: new alternatives.Front Immunol. 2020;11. doi:10.3389/fimmu.2020.02006
Centers for Disease Control and Prevention.About inactive tuberculosis.
Centers for Disease Control and Prevention.Diagnosing tuberculosis.
Muñoz L, Stagg HR, Abubakar I.Diagnosis and management of latent tuberculosis infection.Cold Spring Harb Perspect Med. 2015;5(11):a017830. doi:10.1101/cshperspect.a017830
Centers for Disease Control and Prevention.Treatment for TB disease.
Centers for Disease Control and Prevention.Treatment regimens for latent TB infection.
Centers for Disease Control and Prevention.Guidelines for preventing the transmission of tuberculosis in health-care settings, with special focus on HIV-related issues.
US Preventive Services Task Force, Mangione CM, Barry MJ, et al.Screening for Latent Tuberculosis Infection in Adults: US Preventive Services Task Force Recommendation Statement.JAMA. 2023;329(17):1487-1494. doi:10.1001/jama.2023.4899
Centers for Disease Control and Prevention.About inactive tuberculosis.Centers for Disease Control and Prevention.Diagnosing tuberculosis.
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