Overview
Tuberculosis (TB) is an infectious disease caused by the bacteria mycobacterium tuberculosis. TB primarily affects the lungs. According to the Centers for Disease Control and Prevention (CDC), tuberculosis is one of the world’s most deadly diseases with over 9 million people in the world becoming sick each year. In 2008, 12,904 cases of TB were reported in the United States.
Signs/Symptoms
Two types of tuberculosis conditions exist.
An individual can be infected with the mycobacterium bacteria, but his immune system is able to fight the bacteria and he may not develop active TB disease. This is called latent TB infection. An individual with Latent TB infection does not have any symptom, does not feel sick and cannot transmit tuberculosis to other individuals.
When an individual’s immune system cannot stop the mycobacterium from growing, he will develop active TB disease. Active TB disease manifests as a cough of at least three weeks, pain in the chest, coughing up blood or sputum, fatigue, loss of appetite, chills and fever. Affected patients feel very sick and can transmit the disease to other individuals.
Transmission
Tuberculosis is spread from person to person through the air. When an individual with active TB sneezes, coughs or speaks, other people may breathe in the mycobacterium bacteria and become infected. The CDC states that TB is not spread by sharing food or drink, shaking a person’s hand, toilet seats, kissing or sharing toothbrushes.
Diagnosis
The Mantoux tuberculin test is performed to determine whether a person has been infected with TB; however, the test will not show if an individual has active tuberculosis. During the test, a small amount of fluid is injected into the skin on the arm. After 48 to 72 hours, the site where the fluid was injected is checked by a health care professional for any signs of reaction.
A newer blood test can also be used to test the immune system’s response to mycobacterium.
When a individual has a positive skin test or blood test, it is important for him to be tested for active TB disease. A medical history and physical examination, chest X-ray and sputum sample are necessary to diagnose active TB disease.
Treatment
Individuals with latent TB infection are treated with a prescription of the oral medication isoniazid (INH) for nine months. Side effects of INH include nausea, heartburn and dizziness. Heavy use of alcohol and acetaminophen should be avoided as INH has been shown to cause liver damage. Individuals with HIV and children may need a longer course of INH treatment. Medication should be taken exactly as prescribed to reduce the risk of developing active TB disease.
Individuals with active TB are treated with four oral medications, and hospitalization may be necessary until tests confirm an individual is no longer contagious. Isoniazid, rifampin, ethambutol and pyrazinamide are taken for six to 12 months. The full course of medication should be taken exactly as prescribed to effectively treat TB and prevent a recurrence.
Individuals with treatment resistant TB are more difficult to treat. Closely supervised care and a cocktail of several different medications are necessary as untreated TB can be life-threatening.
Vaccination
Bacille CalmetteGuerin (BCG) is a vaccine for tuberculosis. According to the CDC, the vaccine is not usually given in the United States because the prevalence of active TB is low, the effectiveness of the vaccine is variable and it interferes with skin testing. The vaccine is only given to individuals who meet specific criteria including children who are continually exposed and cannot be separated from adults with untreated or treatment-resistant TB disease. Health care workers should also be vaccinated when they are continually exposed to active TB patients and when infection control precautions in their workplace have failed and transmission is likely to occur.
About this Author
Shelly Guillory has been a registered nurse for seven years, specializing in the areas of oncology, infectious disease, and psychiatric nursing. Guillory has been writing for six years and is currently pursing degrees in journalism and photography at the University of Utah.
