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.
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.
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
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
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
Persons with Medical Conditions that Weaken the Immune System
and young children often have weak immune systems. Other people can
have weak immune systems, too, especially people with any of these
- 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: