TB can be spread in the air by someone who has TB in the lungs or throat when the individual is coughing, singing, talking or sneezing. TB is not spread by touching someone who has TB. Once someone breathes in the bacteria, they can develop latent tuberculosis infection, a condition where the body stops the bacteria from growing.
Someone with latent TB infection does not have symptoms of the disease and is not able to spread the bacteria to others. About 10 percent of the people who have latent TB infection will develop the active disease at some time during their life.
When the TB bacteria continue to grow in the body, the infected person will develop the active form of the disease. Symptoms of active TB disease include:
- having a bad cough that lasts three weeks or longer;
- coughing up blood;
- experiencing weakness or fatigue;
- losing weight;
- having no appetite; and
- having chills and fever and/or sweating at night.
Treatment for TB consists of taking medications to kill the bacteria. The TB bacteria grow slowly, so treatment is required for at least six months to completely kill the germs.
According to experts at the Centers for Disease Control and Prevention (CDC) and the American Thoracic Society, patients should be started on four anti-tuberculosis drugs to prevent the development of drug resistance. Drug resistance leads to TB that is more difficult to treat. The standard of care in Pennsylvania is to begin all suspected and confirmed cases of tuberculosis on four-drug therapy.
Directly Observed Therapy (the visual monitoring by a health care worker of patients' ingestion of medications) is the standard of care for all active cases of TB treated by providers at the Pennsylvania Department of Health. This ensures that all doses of the medications are taken to stop the spread of the disease and prevent the development of drug-resistant TB.
Risk Factors for Tuberculosis
Generally, persons at high risk for developing TB disease fall into two categories:
- persons who have been recently infected with TB bacteria; and
- persons with medical conditions that weaken the immune system.
Persons who have been Recently Infected with TB Bacteria
- close contacts of a person with infectious TB disease;
- persons who have immigrated from areas of the world with high rates of TB;
- children less than 5 years of age who have a positive TB test;
- groups with high rates of TB transmission, such as homeless persons, injection drug users, and persons with HIV infection; and
- persons who work or reside with people who are at high risk for TB in facilities or institutions such as hospitals, homeless shelters, correctional facilities, nursing homes and residential homes for those with HIV.
Persons with Medical Conditions that Weaken the Immune System
Babies and young children often have weak immune systems. Other people can have weak immune systems, too, especially people with any of these conditions:
- HIV infection* (the virus that causes AIDS);
- substance abuse;
- diabetes mellitus;
- severe kidney disease;
- low body weight;
- organ transplants;
- head and neck cancer;
- medical treatments such as corticosteroids or organ transplant;
- specialized treatment for rheumatoid arthritis or Crohn's disease; and
- taking medications that suppress the immune system like chemotherapy.
* TB is the leading killer among people living with HIV, who have weakened immune systems.
Please check with your healthcare provider if you have more questions about TB and your health.
The following TB fact sheets have been prepared for patients by the CDC: