TB FAQs

What is tuberculosis?
Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis, which usually attack the lungs, but can strike any part of the body. Symptoms include a cough that lasts for more than two or three weeks, weight and appetite loss, fever, night sweats and coughing up blood. TB produces an especially lethal combination with HIV: people with HIV are up to 50 times more likely to develop TB in a given year than those who are HIV-negative, and TB kills up to half of all AIDS patients worldwide. TB is often fatal but can be cured if detected early.

Is tuberculosis a serious disease?
Yes. TB is one of the world's most lethal infectious diseases, and it is a growing problem. Overall, one-third of the world's population is currently infected with the TB bacillus. Because it can cause death or grave illness, TB also poses a serious threat to national economies; infected workers lose an average of 3-4 months of work.

Not everyone infected with TB bacteria becomes sick. Some exposed people develop what is called latent TB infection. Those with latent TB infection do not feel sick, do not have any symptoms, and cannot spread TB to others. If people suspect they have been infected, they can take medicine that will keep them from developing active TB disease.

TB can usually be treated with a course of four standard, or first-line, anti-TB drugs. If these drugs are misused or mismanaged, multidrug-resistant TB (MDR-TB) can develop. MDR-TB takes longer to treat with second-line drugs, which are more expensive and have more side effects. If these second-line drugs are also misused or mismanaged, XDR-TB or extensively drug-resistant tuberculosis can develop. Because XDR-TB is resistant to first- and second-line drugs, treatment options are seriously limited. XDR-TB poses a grave public health threat, especially in populations with high rates of HIV and where there are few health care resources.

Where does tuberculosis occur?
Tuberculosis is found in every country in the world. Incidence is especially high throughout Asia and rises to extreme levels in Sub-Saharan Africa, where it is fueling the explosive HIV/AIDS epidemic. HIV/AIDS and TB are so closely connected that the term "co-epidemic" or "dual epidemic" is often used to describe their relationship.

How is tuberculosis transmitted?
TB is spread through the air from one person to another. When a person with active TB disease of the lungs or throat coughs or sneezes, the bacteria is released into the air. If people within close proximity breathe in these bacteria, it can settle in their lungs and begin to grow. From there, the bacteria can move through the blood to other parts of the body, such as the kidney, spine, and brain.

TB in the lungs or throat can be infectious, but TB in other parts of the body, such as the kidney or spine, usually is not. People with active TB disease are most likely to spread it to others with whom they spend most of their time. This includes family members, friends, and coworkers.





TB Prevention & Control

Tuberculosis is a preventable disease, and there are several measures that people can take to help protect themselves and others:

  1. Regular testing for at-risk individuals. Experts advise that people who are at high risk of contracting TB — for example, individuals who have close contact with people with infectious TB, were born in a high-prevalence TB country, or have a weakened immune system as a result of HIV or other diseases, their age, malnutrition, substance abuse, etc. — receive a skin test every six months.
  2. Preventive therapy. Those who test positive for latent TB infection, but have no evidence of active TB, should talk to a professional about isoniazid therapy, which reduces the risk of developing active TB.
  3. Completion of the entire course of medication. It is absolutely essential that people who have begun TB treatment do not discontinue their medication. When a patient prematurely ends treatment or skips doses, TB bacteria have a chance to develop drug-resistant mutations that are much more deadly and difficult to treat.
There is also an internationally recommended strategy to control TB, known as Directly Observed Treatment Short Course (DOTS), which has five components:
  1. Political commitment to sustained TB control. Political commitment fosters national and international partnerships and is linked to long-term strategic action plans. These plans address technical and financial requirements and promote accountability for results at all levels of the health system; they include TB-related and other relevant indicators, and are often supported by national legislation. Local partnerships help improve TB care in terms of access, equity and quality.
  2. Access to quality-assured TB sputum microscopy. Bacteriology is the recommended method of TB case detection, starting with sputum smear microscopy and then progressing to culture and drug susceptibility testing. A wide network of properly equipped laboratories with trained personnel is necessary to ensure access to quality-assured microscopy. Many countries also have a well-resourced and fully functioning national reference laboratory.
  3. Standardized short-course chemotherapy, including direct observation of treatment. The mainstay of TB control is organizing and administering standardized treatment for all TB cases. Use of standard short-course regimens and fixed-dose drug combinations facilitates adherence to treatment and reduces the risk of drug resistance.

    Supervised treatment, which often includes direct observation of therapy, helps patients take their drugs regularly and complete treatment, thus achieving cure and preventing the development of drug resistance. Supervision occurs at a health facility, in the workplace, in the community or at home, and is provided by a treatment partner or treatment supporter, who is both acceptable to the patient and trained and supervised by health services.

    Patient and peer support groups can help to promote treatment adherence. It is also important to take locally appropriate measures to identify and address physical, financial, social and cultural barriers to accessing TB treatment services.
  4. An uninterrupted supply of drugs. A reliable drug procurement and distribution system is a vital element of TB control. A TB recording and reporting system provides the information needed to plan, procure, distribute and maintain adequate drug stocks. Anti-TB drugs should be available free of charge to all TB patients, both because many patients cannot afford them and because because treatment benefits the entire society.
  5. A standardized recording and reporting system. Maintaining reliable monitoring and evaluation with regular communication between the central and peripheral levels of the health system is vital. This requires standardized recording of individual patient data, including information on treatment outcomes, which is then used to compile quarterly treatment outcome reports in patient cohorts. These data are used at the facility level to monitor treatment outcomes, at the district level to identify local problems , at provincial or national level to ensure consistently high-quality TB control across geographical areas, and nationally and internationally to evaluate country performance.


** Sources: Mayo Clinic and the World Health Organization (WHO)




TB Diagnosis & Treatment

Fever, inexplicable weight loss, night sweats, chills, appetite loss and a persistent cough are all symptoms suggestive of tuberculosis infection. Infection can be confirmed through a simple skin test: a small amount of PPD tuberculin is injected just beneath the skin of the inside forearm. A positive response — shown by a hard, raised bump at the injection site — means that infection is likely; this will usually lead to further tests, including chest x-rays and culture tests.

Tuberculosis is treated with a combination of antibiotics for at least 6 months and is most effectively combated with an approach that emphasizes DOT (Directly Observed Therapy). Under this strategy, nurses or other health care professionals actually administer each dose of anti-tuberculosis medications, thereby maximizing the likelihood that patients will complete their entire therapy course. A comprehensive, patient-centered approach to case management supports DOT with an array of ancillary elements, including social services, treatment incentives and enablers, housing assistance, substance abuse treatment referral, and coordination of tuberculosis services with other providers.

It is imperative to complete the entire course of drugs as directed, even if the patient begins to feel better before treatment completion. If the TB bacteria is not completely eradicated, drug-resistant strains may develop, causing illness resurgence. Drug-resistant bacteria have become an increasingly serious problem; some strains have developed a resistance to the two leading TB medications, which is defined as multi-drug resistance (MDR). MDR-TB can be treated, but it requires at least two years of therapy with second-line medications that can be highly toxic. Even with treatment, about half of people with MDR-TB may not survive. In addition, treating MDR-TB is far more costly than treating nonresistant TB, making this therapy unaffordable in many parts of the world.

** Sources: US National Center for Infectious Diseases, Mayo Clinic, UK National Health Service