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Health Tips
Tuberculosis (TB)
Stop TB Mission
Stop TB
Our mission is to increase access, security, and support to:
- Ensure that every TB patient has access to TB treatment and cure
- Protect vulnerable populations from TB
- Reduce the social and economic toll that TB exerts on families, communities, and nations
TB Statistics
- Someone dies of TB every 15 seconds.
- Eight million people develop active TB every year.
- Each one can infect between 10 and 15 people in one year just by breathing.
- The best way to prevent TB is to treat and cure people who have it.
- TB causes more deaths among women than all causes of maternal mortality combined.
- Over 900 million women are infected with TB worldwide, one million will die and 2.5 million will get sick this year from the disease, mainly between the ages of 15 and 44.
More Stats...
World Health Organization
- TB kills about 2 million people each year.
- Over 1.5 million TB cases per year occur in sub-Saharan Africa. This number is rising rapidly as a result of the HIV/AIDS epidemic.
- Nearly 3 million TB cases per year occur in south-east Asia.
- Over a quarter of a million TB cases per year occur in Eastern Europe.
CDC National Center for HIV, STD and TB Prevention
Division of Tuberculosis Elimination
What is TB?
TB, or tuberculosis, is a disease caused by bacteria called Mycobacterium tuberculosis. The bacteria can attack any part of your body, but they usually attack the lungs. TB disease was once the leading cause of death in the United States.
People who are infected with latent TB do not feel sick, do not have any symptoms, and cannot spread TB. But they may develop TB disease at some time in the future. People with TB disease can be treated and cured if they seek medical help. Even better, people who have latent TB infection but are not yet sick can take medicine so that they will never develop TB disease.
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 or sneezes. 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 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.
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 to others
- usually have a positive skin test reaction
- can develop TB disease later in life if they do not receive treatment for latent TB infection
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 and cause TB disease.
What is TB disease?
TB bacteria become active if the immune system can't stop them from growing. The active bacteria begin to multiply in the body and cause TB disease. Some people develop TB disease soon after becoming infected, before their immune system can fight the TB bacteria. Other people may get sick later, when their immune system becomes weak for some 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)
Symptoms of TB depend on where in the body the TB bacteria are growing. TB bacteria usually grow in the lungs. TB in the lungs may cause
- a bad cough that lasts longer than 2 weeks
- 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
NIH - Ntnl Institute of Allergy and Infectious Diseases
NIH NIAID
Is TB a problem in the United States?
In the United States, TB has re-emerged as a serious public health problem. In 2000, a total of 16,377 cases of active TB (infection with full-blown disease symptoms), were reported to the Centers for Disease Control and Prevention (CDC). Thanks largely to improved public health control measures, this represents a 45 percent decrease in cases since 1992. In addition to those with active TB, however, an estimated 10 to 15 million people in the United States are infected with M. tuberculosis without displaying symptoms (latent TB) and about one in ten of these individuals will develop active TB at some time in their lives.
Minorities are affected disproportionately by TB: 54 percent of active TB cases in 1999 were among African-American and Hispanic people, with an additional 20 percent found in Asians.
What caused TB to return?
Cases of TB dropped rapidly in the 1940s and 1950s when the first effective antibiotic therapies for TB were introduced. In 1985, however, the decline ended and the number of active TB cases in the United States began to rise again. Several forces, often interrelated, were behind TB's resurgence:
- The HIV/AIDS epidemic. People with HIV are particularly vulnerable to turn infection with M. tuberculosis into active TB and are also more sensitive to developing active TB when they are first infected with the TB germ.
- Increased numbers of foreign born nationals from countries where many cases of TB occur, such as Africa, Asia, and Latin America. TB cases among those persons now living in the US account for 43 percent of the national total.
- Increased poverty, injection drug use, and homelessness. TB transmission is rampant in crowded shelters and prisons where people weakened by poor nutrition, drug addiction, and alcoholism are exposed to M. tuberculosis.
- Failure of patients to take their prescribed antibiotics against TB as directed.
- Increased numbers of residents in long-term care facilities such as nursing homes. Many develop active TB from infections with M. tuberculosis that occurred much earlier in life because their general health has declined. Other elderly people, especially those with weak immune systems, become newly infected with M. tuberculosis and can rapidly develop active TB.
What happens when someone gets infected with M. tuberculosis?
Between two to eight weeks after being infected with M. tuberculosis, a person's immune system responds to the TB germ by walling off infected cells. From then on the body maintains a standoff with the infection, sometimes for years. Most people undergo complete healing of their initial infection, and the bacteria eventually die off. A positive TB skin test, and old scars on a chest x-ray, may provide the only evidence of the infection.
If, however, the body's resistance is low because of aging, infections such as HIV, malnutrition, or other reasons, the bacteria may break out of hiding and cause active TB.
How is TB diagnosed?
Doctors can identify most people infected with M. tuberculosis with a skin test. They will inject a substance under the skin of the forearm. If a red welt forms around the injection site within 72 hours, the person may have been infected. This doesn't necessarily mean he or she has active disease. Most people with previous exposure to M. tuberculosis will test positive on the tuberculin test, as will some people exposed to bacteria that are related to the TB germ.
If a person has an obvious reaction to the skin test, other methods can help to show if the individual has active TB. In making a diagnosis, doctors rely on symptoms and other physical signs, a person's history of exposure to TB, and x-rays that may show evidence of M. tuberculosis infection.
The doctor also will take sputum and other samples, to see if the TB bacteria will grow in the lab. If bacteria are growing, this positive culture confirms the diagnosis of TB. Because M. tuberculosis grows very slowly, it can take four weeks to confirm the diagnosis. An additional two to three weeks usually are needed to determine which antibiotics the bacteria are susceptible to.
Can TB be cured?
With appropriate antibiotic treatment, TB can be cured in more than nine out of ten patients.
Successful treatment of TB depends on close cooperation between the patient and doctor and other health care workers. Treatment usually combines several different antibiotic drugs which are given for at least six months, sometimes for as long as 12 months.
Patients must take their medicine on time every day for the 6 to 12 months. Some TB patients stop taking their prescribed medicines because they may feel better after only a couple of weeks of treatment. Another reason they may stop taking their medicine is because TB drugs can have unpleasant side effects.
Why is it so important to finish all of the TB medicine?
If patients don't take all their medicine the way their doctor tells them, they can become sick again and spread TB to their friends and family. Additionally, when patients do not take all the drugs the doctor has prescribed or skip times when they are supposed to take them, the TB bacteria learn to outwit the TB antibiotics, and soon those medications no longer work against the disease. If this happens, the person now has resistant TB infection. Some patients have disease that is resistant to two or more drugs. This is called multidrug-resistant TB or MDR-TB because the TB germ, M. tuberculosis resists eradication with more than drug. This form of TB is much more difficult to cure.
How is TB prevented?
TB is largely a preventable disease. In the United States, doctors try to identify persons infected with M. tuberculosis as early as possible, before they have developed active TB. They will give a drug called isoniazid (INH) to prevent the active disease. This drug is given every day for 6 to 12 months. INH can cause hepatitis in a small percentage of patients, especially those older than 35 years. A nurse may watch the patients take their medicine to make sure all pills are taken.
Hospitals and clinics can take precautions to prevent the spread of TB. Precautions include using ultraviolet light to sterilize the air, special filters, and special respirators and masks. Until they can no longer spread the TB germs, TB patients in hospitals should be isolated in special rooms with controlled ventilation and airflow.
Is there a vaccine for TB?
In those parts of the world where the disease is common, the World Health Organization (WHO) recommends that infants receive a vaccine called BCG made from a live weakened bacterium related to M. tuberculosis. BCG vaccine prevents M. tuberculosis from spreading within the body, thus preventing TB from developing.
However, the vaccine has its drawbacks. It does not protect adults very well against TB. In addition, BCG interferes with the TB skin test, showing a positive skin test reaction in people who have received BCG vaccine. In countries where BCG vaccine is used, the ability of the skin test to identify persons that are infected with M. tuberculosis is limited. Because of these limitations, more effective vaccines are needed and BCG is not recommended for general use in the United States.
How is M. tuberculosis infection different in people with HIV infection?
The World Health Organization (WHO) estimates that 10 million people worldwide are infected with the M. tuberculosis bacterium and HIV virus at the same time. The primary cause of death in these patients is from TB, not AIDS. In the United States, it is estimated that about 2 out of ten persons who have TB are also infected with HIV.
One of the first indications that a person is infected with HIV may be that he or she suddenly develops TB. This form of TB often occurs in areas outside the lungs, particularly when the patient is in the later stages of AIDS.
In the United States, it is much more likely for persons infected with M. tuberculosis and HIV to develop active TB than it is for someone that is only infected with M. tuberculosis. However, TB disease can be prevented and cured, even in people with HIV infection.
People with MDR-TB that are also infected with HIV appear to have a more rapid and deadly disease course than do those patients with MDR-TB who are otherwise healthy. If no medicines are available for these patients as many as eight out of ten may die, often within months of diagnosis.
Diagnosing TB in HIV-infected people is often difficult. HIV infected patients frequently have disease symptoms similar to those of TB, and may not react to the standard TB skin test because their immune system does not work properly. X-rays, sputum tests, and physical exams may also fail to provide evidence of infection with M. tuberculosis in HIV-infected individuals.
Poorly managed TB programs are threatening to make TB incurable
Stop TB
Until 50 years ago, there were no medicines to cure TB. Strains that are resistant to a single drug or even a combination of drugs have now emerged. Many millions may be infected with drug-resistant TB. There is no cure affordable to developing countries for some multidrug-resistant (MDR) strains, defined as resistant to the two most important drugs, isoniazid and rifampicin.
MDR-TB is caused by inconsistent or partial treatment, when patients do not take all their medicines regularly for the required period because they start to feel better, doctors and health workers prescribe the wrong drugs or the wrong combination of drugs, or the drug supply is unreliable.
From a public health perspective, poorly supervised and incomplete treatment of TB is worse than no treatment at all. When people fail to complete standard treatment regimens or are given the wrong treatment, they may remain infectious. The bacilli in their lungs may develop resistance to anti-TB drugs. People they infect will have the same drug-resistant strain. Drug-resistant TB is more difficult and more expensive to treat, and more likely to be fatal. In industrialized countries TB treatment costs around US $2,000 per patient, but rises more than 100-fold to up to US $250,000 per patient with MDR-TB.
DOTS cures up to 95% of drug-susceptible patients, but these cure rates fall well below an acceptable rate in areas of high MDR. Thus drug-resistance threatens the success of DOTS and global TB control.
Effective TB Control
World Health Organization
The WHO-recommended treatment strategy for detection and cure of TB is DOTS. DOTS combines five elements: political commitment, microscopy services, drug supplies, surveillance and monitoring systems and use of highly efficacious regimes with direct observation of treatment.
Once patients with infectious TB (bacilli visible in a sputum smear) have been identified using microscopy services, health and community workers and trained volunteers observe and record patients swallowing the full course of the correct dosage of anti-TB medicines (treatment lasts six to eight months). The most common anti-TB drugs are isoniazid, rifampicin, pyrazinamide, streptomycin and ethambutol.
Sputum smear testing is repeated after two months, to check progress, and again at the end of treatment. A recording and reporting system documents patients' progress throughout, and the final outcome of treatment.
- DOTS produces cure rates of up to 95 percent even in the poorest countries.
- DOTS prevents new infections by curing infectious patients.
- DOTS prevents the development of MDR-TB by ensuring the full course of treatment is followed.
- A six-month supply of drugs for DOTS costs US $11 per patient in some parts of the world. The World Bank has ranked the DOTS strategy as one of the "most cost-effective of all health interventions."
Tuberculosis in prisons
Stop TB
- The level of TB in prisons has been reported to be up to 100 times higher than that of the civilian population.
- Cases of TB in prisons may account for up to 25% of a country's burden of TB.
- Late diagnosis, inadequate treatment, overcrowding, poor ventilation and repeated prison transfers encourage the transmission of TB infection.
- HIV infection and other pathology more common in prisons (e.g. malnutrition, substance abuse) encourage the development of active disease and further transmission of infection.
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