Tuberculosis is an airborne bacteria that can spread to any of the body’s organs but is mostly found in the lungs. The bacteria are put into the air when a person with active TB disease of the lungs or throat coughs, sneezes, speaks or sings. People nearby may breathe in these bacteria and become infected. However, not everyone infected with TB bacteria becomes sick.
Of all the TB cases reported from 1991-2001 in the United States, almost 80 percent were in racial and ethnic minorities. Asian Americans and Pacific Islanders accounted for 22 percent of those cases, even though they made up less than 4 percent of the U.S. population.[1]
Symptoms of TB depend on where in the body the TB bacteria are growing. TB in the lungs may cause symptoms such as: 2
- A bad cough that lasts three weeks or longer
- Pain in the chest
- Coughing up blood or sputum (phlegm from deep inside the lungs)
Other symptoms of active TB disease are:
- Weakness or fatigue
- Weight loss
- No appetite
- Chills
- Fever
- Sweating at night
Certain factors increase an individual’s risk for tuberculosis:[2]
- Lowered immunity. A healthy immune system can often successfully fight TB bacteria, but your body can’t mount an effective defense if your resistance is low. Having a disease that suppresses immunity, such as HIV/AIDS, diabetes, end-stage kidney disease, certain cancers or the lung disease silicosis, can reduce your body’s ability to protect itself. Your risk is also higher if you take corticosteroids, certain arthritis medications, chemotherapy drugs or other drugs that suppress the immune system.
- Country of origin. People from regions with high rates of TB — especially sub-Saharan Africa, India, China, the islands of Southeast Asia and Micronesia, and parts of the former Soviet Union — are more likely to develop TB.
- Age. Older adults are at greater risk of TB because normal aging or illness may weaken their immune systems.
- Substance abuse. Long-term drug or alcohol use weakens your immune system and makes you more vulnerable to TB.
- Malnutrition. A poor diet or one too low in calories puts you at greater risk of TB.
- Health care work. Regular contact with people who are ill increases your chances of exposure to TB bacteria. Wearing a mask and frequent hand washing greatly reduce your risk.
[1] Disease Burden & Risk Factors. Office of Minority Health & Health Disparities. Centers for Disease Control and Prevention. Available at: http://www.cdc.gov/omhd/AMH/dbrf.htm. Accessed June 8, 2009.
[2] Tuberculosis Risk Factors. The Mayo Clinic. Available at http://www.mayoclinic.com/health/tuberculosis/DS00372/DSECTION=risk-factors. Accessed June 8, 2009.